Imaging

What is the diagnosis?

Is additional imaging necessary, and if so, why?

An 83-year-old woman with history of hypertension, hyperlipidemia, coronary artery disease, and gastroesophageal reflux disease presents to the ED with epigastric abdominal pain. Contrast-enhanced computed tomography (CT) was obtained; a coronal reformatted image is shown above (Figure 1).

Answer

Mirizzi syndrome, partial obstruction of the common hepatic duct by a large gallstone at the gallbladder neck (as in this patient) or within the cystic duct, was first described by Argentinian surgeon Pablo Mirizzi in the mid-20th century. Although Mirizzi syndrome occurs in less than 3% of all patients with cholelithiasis, the inflammation and fibrosis associated with this condition can lead to cholecystobiliary or choledochobiliary fistula formation. Preoperatively unrecognized cases are associated with increased morbidity and mortality compared with uncomplicated cholelithiasis. Cholecystectomy in patients with Mirizzi syndrome is often performed via an open rather than laparoscopic approach, and biliary fistula may require surgical repair with choledochoduodenostomy. 1-3

The recommended initial imaging modality for patients with clinical signs of biliary obstruction (eg, jaundice and/or intermittent cholangitis) is right upper quadrant ultrasound based on its greater sensitivity for gallstone detection compared to CT and wider availability than magnetic resonance imaging (MRI). If ultrasound demonstrates central biliary ductal prominence with calculi at the gallbladder neck and/or cystic duct, further noninvasive imaging with MRI/magnetic resonance cholangiopancreatography (MRCP) should be considered to evaluate for Mirizzi syndrome, as well as to exclude more distal common bile duct obstruction/stricture that may not be visible sonographically.

Based on this patient’s nonspecific epigastric pain, CT imaging was evaluated before ultrasound. While the CT findings and elevated liver function tests suggested Mirizzi syndrome, MRCP was subsequently performed to better characterize the partial biliary obstruction, evaluate for biliary fistula, and exclude noncalcified stones within the biliary tree.

The coronal CT image demonstrates two calcified stones within the gallbladder—a large stone more superiorly at the gallbladder neck and a smaller stone more inferiorly at the gallbladder fundus (black arrows, Figure 2)—with diffuse gallbladder wall thickening/ edema, suspicious for acute cholecystitis. Focal narrowing of the common hepatic duct (white arrow, Figure 2) was caused by the larger stone as it crosses the gallbladder neck with postobstructive dilatation of the more proximal/superior aspect of the common hepatic duct (yellow arrow, Figure 2).

Maximum intensity projection from MRCP reveals the large gallstone at the gallbladder neck as a filling defect (black arrow, Figure 3), with focal compression of the adjacent common hepatic duct (yellow arrow, Figure 3). The more downstream common bile duct (white arrow, Figure 3) is of normal caliber without filling defect. Coronal single-shot fast spin echo image from the same examination again demonstrates narrowing of the common hepatic duct with associated upstream prominence of the central hepatic bile ducts (white arrow, Figure 4).

Given her advanced age, comorbidities, and lowimaging suspicion for biliary fistula, the patient in this case underwent successful laparoscopic, rather than open, cholecystectomy without complication.

What is the diagnosis?

Is additional imaging necessary, and if so, why?

An 83-year-old woman with history of hypertension, hyperlipidemia, coronary artery disease, and gastroesophageal reflux disease presents to the ED with epigastric abdominal pain. Contrast-enhanced computed tomography (CT) was obtained; a coronal reformatted image is shown above (Figure 1).

Answer

Mirizzi syndrome, partial obstruction of the common hepatic duct by a large gallstone at the gallbladder neck (as in this patient) or within the cystic duct, was first described by Argentinian surgeon Pablo Mirizzi in the mid-20th century. Although Mirizzi syndrome occurs in less than 3% of all patients with cholelithiasis, the inflammation and fibrosis associated with this condition can lead to cholecystobiliary or choledochobiliary fistula formation. Preoperatively unrecognized cases are associated with increased morbidity and mortality compared with uncomplicated cholelithiasis. Cholecystectomy in patients with Mirizzi syndrome is often performed via an open rather than laparoscopic approach, and biliary fistula may require surgical repair with choledochoduodenostomy. 1-3

The recommended initial imaging modality for patients with clinical signs of biliary obstruction (eg, jaundice and/or intermittent cholangitis) is right upper quadrant ultrasound based on its greater sensitivity for gallstone detection compared to CT and wider availability than magnetic resonance imaging (MRI). If ultrasound demonstrates central biliary ductal prominence with calculi at the gallbladder neck and/or cystic duct, further noninvasive imaging with MRI/magnetic resonance cholangiopancreatography (MRCP) should be considered to evaluate for Mirizzi syndrome, as well as to exclude more distal common bile duct obstruction/stricture that may not be visible sonographically.

Based on this patient’s nonspecific epigastric pain, CT imaging was evaluated before ultrasound. While the CT findings and elevated liver function tests suggested Mirizzi syndrome, MRCP was subsequently performed to better characterize the partial biliary obstruction, evaluate for biliary fistula, and exclude noncalcified stones within the biliary tree.

The coronal CT image demonstrates two calcified stones within the gallbladder—a large stone more superiorly at the gallbladder neck and a smaller stone more inferiorly at the gallbladder fundus (black arrows, Figure 2)—with diffuse gallbladder wall thickening/ edema, suspicious for acute cholecystitis. Focal narrowing of the common hepatic duct (white arrow, Figure 2) was caused by the larger stone as it crosses the gallbladder neck with postobstructive dilatation of the more proximal/superior aspect of the common hepatic duct (yellow arrow, Figure 2).

Maximum intensity projection from MRCP reveals the large gallstone at the gallbladder neck as a filling defect (black arrow, Figure 3), with focal compression of the adjacent common hepatic duct (yellow arrow, Figure 3). The more downstream common bile duct (white arrow, Figure 3) is of normal caliber without filling defect. Coronal single-shot fast spin echo image from the same examination again demonstrates narrowing of the common hepatic duct with associated upstream prominence of the central hepatic bile ducts (white arrow, Figure 4).

Given her advanced age, comorbidities, and lowimaging suspicion for biliary fistula, the patient in this case underwent successful laparoscopic, rather than open, cholecystectomy without complication.

What is the diagnosis?

Is additional imaging necessary, and if so, why?

An 83-year-old woman with history of hypertension, hyperlipidemia, coronary artery disease, and gastroesophageal reflux disease presents to the ED with epigastric abdominal pain. Contrast-enhanced computed tomography (CT) was obtained; a coronal reformatted image is shown above (Figure 1).

Answer

Mirizzi syndrome, partial obstruction of the common hepatic duct by a large gallstone at the gallbladder neck (as in this patient) or within the cystic duct, was first described by Argentinian surgeon Pablo Mirizzi in the mid-20th century. Although Mirizzi syndrome occurs in less than 3% of all patients with cholelithiasis, the inflammation and fibrosis associated with this condition can lead to cholecystobiliary or choledochobiliary fistula formation. Preoperatively unrecognized cases are associated with increased morbidity and mortality compared with uncomplicated cholelithiasis. Cholecystectomy in patients with Mirizzi syndrome is often performed via an open rather than laparoscopic approach, and biliary fistula may require surgical repair with choledochoduodenostomy. 1-3

The recommended initial imaging modality for patients with clinical signs of biliary obstruction (eg, jaundice and/or intermittent cholangitis) is right upper quadrant ultrasound based on its greater sensitivity for gallstone detection compared to CT and wider availability than magnetic resonance imaging (MRI). If ultrasound demonstrates central biliary ductal prominence with calculi at the gallbladder neck and/or cystic duct, further noninvasive imaging with MRI/magnetic resonance cholangiopancreatography (MRCP) should be considered to evaluate for Mirizzi syndrome, as well as to exclude more distal common bile duct obstruction/stricture that may not be visible sonographically.

Based on this patient’s nonspecific epigastric pain, CT imaging was evaluated before ultrasound. While the CT findings and elevated liver function tests suggested Mirizzi syndrome, MRCP was subsequently performed to better characterize the partial biliary obstruction, evaluate for biliary fistula, and exclude noncalcified stones within the biliary tree.

The coronal CT image demonstrates two calcified stones within the gallbladder—a large stone more superiorly at the gallbladder neck and a smaller stone more inferiorly at the gallbladder fundus (black arrows, Figure 2)—with diffuse gallbladder wall thickening/ edema, suspicious for acute cholecystitis. Focal narrowing of the common hepatic duct (white arrow, Figure 2) was caused by the larger stone as it crosses the gallbladder neck with postobstructive dilatation of the more proximal/superior aspect of the common hepatic duct (yellow arrow, Figure 2).

Maximum intensity projection from MRCP reveals the large gallstone at the gallbladder neck as a filling defect (black arrow, Figure 3), with focal compression of the adjacent common hepatic duct (yellow arrow, Figure 3). The more downstream common bile duct (white arrow, Figure 3) is of normal caliber without filling defect. Coronal single-shot fast spin echo image from the same examination again demonstrates narrowing of the common hepatic duct with associated upstream prominence of the central hepatic bile ducts (white arrow, Figure 4).

Given her advanced age, comorbidities, and lowimaging suspicion for biliary fistula, the patient in this case underwent successful laparoscopic, rather than open, cholecystectomy without complication.

Either intensive CT imaging or frequent testing of blood levels of carcinoembryonic antigen is more likely to detect a colon cancer recurrence than is minimal follow-up, according to a report published online Jan. 14 in JAMA.

However, combining the two monitoring strategies doesn’t add to the effectiveness of either one at detecting recurrences, said Dr. John N. Primrose of the University of Southampton (England) and his associates in the FACS (Follow-Up After Colorectal Surgery) randomized clinical trial.

Several previous trials have compared different follow-up strategies for patients who have undergone potentially curative surgery – monitoring that is done in the hope that survival will be increased if metastatic disease is identified and treated before it becomes symptomatic. But these studies were of "modest" quality and failed to show any significant treatment effect on disease-specific survival, prompting calls for higher-quality trials.

The FACS, commissioned by the U.K. National Institute for Health Research, was undertaken to assess the two follow-up strategies that are available and affordable and have the greatest potential to detect isolated metastatic recurrence at an early, surgically treatable stage: serial CEA measurement and serial CT imaging of the chest, abdomen, and pelvis.

The FACS involved 1,202 patients already treated for primary colon cancer who had no residual disease and microscopically clear margins. They were scheduled to be followed for 5 years at 39 medical centers in the United Kingdom.

These participants were randomly assigned to any one of four study groups:

• CEA follow-up, with measurement of blood CEA every 3 months for 2 years, then every 6 months for the remaining 3 years, and with a single CT scan at 18 months of the chest, abdomen, and pelvis (302 patients).

• CT follow-up, with CT scans of the same regions every 6 months for 2 years, then annually for the remaining 3 years (302 patients).

• Combined CEA and CT follow-up (303 patients).

• Minimal follow-up (the control group), with only a single CT scan at 12-18 months if the hospital clinician requested one at study entry (304 patients).

Follow-up colonoscopy was provided to all the patients because it is standard treatment in such cases.

Colon cancer recurred in 199 patients.

The primary outcome measure was surgery for colon cancer recurrence after a minimum of 3 years, to help distinguish true recurrence from residual disease that was missed at the initial surgery. (Neither overall nor cancer-specific mortality could be used as a primary outcome measure because the sample size was too small and the follow-up period too short for sufficient power to estimate survival accurately.)

This rate was higher with all of the interventions, compared with minimal follow-up. Surgery for recurrence was performed in 6.7% of the CEA-only group, 8% of the CT-only group, and 6.6% of the combined CEA plus CT group, compared with only 2.3% of the control group, according to the investigators (JAMA 2014;311:263-70 [doi:10.1001/jama.2013.285718]).

These rates for the three intensive interventions were not significantly different from each other, indicating that CEA and CT follow-up yielded comparable early detection of recurrences. No additive effect was seen for combining the two strategies.

The results of a per-protocol analysis, which excluded the 308 patients who did not adhere strictly to the study protocol, were consistent with those of the main analysis.

The study findings indicate that only 12-20 patients need to be followed up using either CEA or CT to identify one potentially curable recurrence, Dr. Primrose and his associates said.

They added that they are continuing follow-up so they can more accurately assess disease-specific mortality. "If there is a survival advantage to any [follow-up] strategy, it is likely to be small," they noted.

The FACS trial was funded by the U.K. National Institute for Health Research Health Technology Assessment program. No financial conflicts of interest were reported.

Either intensive CT imaging or frequent testing of blood levels of carcinoembryonic antigen is more likely to detect a colon cancer recurrence than is minimal follow-up, according to a report published online Jan. 14 in JAMA.

However, combining the two monitoring strategies doesn’t add to the effectiveness of either one at detecting recurrences, said Dr. John N. Primrose of the University of Southampton (England) and his associates in the FACS (Follow-Up After Colorectal Surgery) randomized clinical trial.

Several previous trials have compared different follow-up strategies for patients who have undergone potentially curative surgery – monitoring that is done in the hope that survival will be increased if metastatic disease is identified and treated before it becomes symptomatic. But these studies were of "modest" quality and failed to show any significant treatment effect on disease-specific survival, prompting calls for higher-quality trials.

The FACS, commissioned by the U.K. National Institute for Health Research, was undertaken to assess the two follow-up strategies that are available and affordable and have the greatest potential to detect isolated metastatic recurrence at an early, surgically treatable stage: serial CEA measurement and serial CT imaging of the chest, abdomen, and pelvis.

The FACS involved 1,202 patients already treated for primary colon cancer who had no residual disease and microscopically clear margins. They were scheduled to be followed for 5 years at 39 medical centers in the United Kingdom.

These participants were randomly assigned to any one of four study groups:

• CEA follow-up, with measurement of blood CEA every 3 months for 2 years, then every 6 months for the remaining 3 years, and with a single CT scan at 18 months of the chest, abdomen, and pelvis (302 patients).

• CT follow-up, with CT scans of the same regions every 6 months for 2 years, then annually for the remaining 3 years (302 patients).

• Combined CEA and CT follow-up (303 patients).

• Minimal follow-up (the control group), with only a single CT scan at 12-18 months if the hospital clinician requested one at study entry (304 patients).

Follow-up colonoscopy was provided to all the patients because it is standard treatment in such cases.

Colon cancer recurred in 199 patients.

The primary outcome measure was surgery for colon cancer recurrence after a minimum of 3 years, to help distinguish true recurrence from residual disease that was missed at the initial surgery. (Neither overall nor cancer-specific mortality could be used as a primary outcome measure because the sample size was too small and the follow-up period too short for sufficient power to estimate survival accurately.)

This rate was higher with all of the interventions, compared with minimal follow-up. Surgery for recurrence was performed in 6.7% of the CEA-only group, 8% of the CT-only group, and 6.6% of the combined CEA plus CT group, compared with only 2.3% of the control group, according to the investigators (JAMA 2014;311:263-70 [doi:10.1001/jama.2013.285718]).

These rates for the three intensive interventions were not significantly different from each other, indicating that CEA and CT follow-up yielded comparable early detection of recurrences. No additive effect was seen for combining the two strategies.

The results of a per-protocol analysis, which excluded the 308 patients who did not adhere strictly to the study protocol, were consistent with those of the main analysis.

The study findings indicate that only 12-20 patients need to be followed up using either CEA or CT to identify one potentially curable recurrence, Dr. Primrose and his associates said.

They added that they are continuing follow-up so they can more accurately assess disease-specific mortality. "If there is a survival advantage to any [follow-up] strategy, it is likely to be small," they noted.

The FACS trial was funded by the U.K. National Institute for Health Research Health Technology Assessment program. No financial conflicts of interest were reported.

Either intensive CT imaging or frequent testing of blood levels of carcinoembryonic antigen is more likely to detect a colon cancer recurrence than is minimal follow-up, according to a report published online Jan. 14 in JAMA.

However, combining the two monitoring strategies doesn’t add to the effectiveness of either one at detecting recurrences, said Dr. John N. Primrose of the University of Southampton (England) and his associates in the FACS (Follow-Up After Colorectal Surgery) randomized clinical trial.

Several previous trials have compared different follow-up strategies for patients who have undergone potentially curative surgery – monitoring that is done in the hope that survival will be increased if metastatic disease is identified and treated before it becomes symptomatic. But these studies were of "modest" quality and failed to show any significant treatment effect on disease-specific survival, prompting calls for higher-quality trials.

The FACS, commissioned by the U.K. National Institute for Health Research, was undertaken to assess the two follow-up strategies that are available and affordable and have the greatest potential to detect isolated metastatic recurrence at an early, surgically treatable stage: serial CEA measurement and serial CT imaging of the chest, abdomen, and pelvis.

The FACS involved 1,202 patients already treated for primary colon cancer who had no residual disease and microscopically clear margins. They were scheduled to be followed for 5 years at 39 medical centers in the United Kingdom.

These participants were randomly assigned to any one of four study groups:

• CEA follow-up, with measurement of blood CEA every 3 months for 2 years, then every 6 months for the remaining 3 years, and with a single CT scan at 18 months of the chest, abdomen, and pelvis (302 patients).

• CT follow-up, with CT scans of the same regions every 6 months for 2 years, then annually for the remaining 3 years (302 patients).

• Combined CEA and CT follow-up (303 patients).

• Minimal follow-up (the control group), with only a single CT scan at 12-18 months if the hospital clinician requested one at study entry (304 patients).

Follow-up colonoscopy was provided to all the patients because it is standard treatment in such cases.

Colon cancer recurred in 199 patients.

The primary outcome measure was surgery for colon cancer recurrence after a minimum of 3 years, to help distinguish true recurrence from residual disease that was missed at the initial surgery. (Neither overall nor cancer-specific mortality could be used as a primary outcome measure because the sample size was too small and the follow-up period too short for sufficient power to estimate survival accurately.)

This rate was higher with all of the interventions, compared with minimal follow-up. Surgery for recurrence was performed in 6.7% of the CEA-only group, 8% of the CT-only group, and 6.6% of the combined CEA plus CT group, compared with only 2.3% of the control group, according to the investigators (JAMA 2014;311:263-70 [doi:10.1001/jama.2013.285718]).

These rates for the three intensive interventions were not significantly different from each other, indicating that CEA and CT follow-up yielded comparable early detection of recurrences. No additive effect was seen for combining the two strategies.

The results of a per-protocol analysis, which excluded the 308 patients who did not adhere strictly to the study protocol, were consistent with those of the main analysis.

The study findings indicate that only 12-20 patients need to be followed up using either CEA or CT to identify one potentially curable recurrence, Dr. Primrose and his associates said.

They added that they are continuing follow-up so they can more accurately assess disease-specific mortality. "If there is a survival advantage to any [follow-up] strategy, it is likely to be small," they noted.

The FACS trial was funded by the U.K. National Institute for Health Research Health Technology Assessment program. No financial conflicts of interest were reported.

CHICAGO – Coronary computed tomography angiography with diagnostic image quality is feasible at an ultralow radiation dose of 0.2 millisievert using model-based iterative reconstruction.

This represents roughly an 80% reduction in radiation dose compared with standard coronary CT angiography, Dr. Julia Stehli said at the annual meeting of the Radiological Society of North America.

Increasing concerns about radiation exposure have prompted the use of prospective ECG triggering to reduce radiation doses from 20 mSv to 2 mSv or less. Several vendors also have developed new raw-data–based iterative reconstruction algorithms to further reduce radiation doses, but the trade-off can be increased image noise.

The model-based iterative reconstruction (MIBR) algorithm (GE Healthcare), however, has shown promising results for noise reduction, said Dr. Stehli of University Hospital Zurich. The technology, known as Veo, is already in use in the United States, Europe, and Asia for abdominal CT scans but is not yet commercially available for cardiac scans because of the added complexity of ECG triggering.

Dr. Stehli reported on the hospital’s first clinical experience with MIBR in 25 consecutive prospectively enrolled patients with suspected coronary artery disease who underwent standard low-dose coronary CT angiography (CCTA) and same-day ultralow-dose CCTA on a 64-slice CT scanner with prospective ECG triggering. Tube voltage and current were adapted to body mass index, which covered a wide range from 18.4 kg/m² to 40.2 kg/m². Contrast media volume and flow rate were adapted to body surface area. Intravenous beta-blockers were used prior to CCTA in 20 patients.

Standard CCTA was reconstructed using 30% of adaptive statistical iterative reconstruction (ASIR) according to usual hospital practice, while the ultralow-dose images were sent to the vendor for reconstruction with MIBR.

The effective radiation dose was 1.3 mSv with standard CCTA and 0.2 mSv in the ultralow-dose CCTA group (P less than .001), which is in the range reported for a postero-anterior and lateral chest X-ray, Dr. Stehli said.

A total of 100 vessels and 330 coronary artery segments were semiquantitatively assessed by two blinded, independent readers using a 4-point Likert scale, with 1 being nondiagnostic, 2 good, 3 adequate, and 4 excellent. The Kappa value for interobserver agreement of image quality was 0.8.

The average image quality score per segment was 3.3 with standard CCTA vs. 3.4 with ultralow-dose MBIR (P less than .05), she said.

Diagnostic image quality (score 2-4) was found in 319 segments (97%) and 317 segments (96%), respectively.

"These numbers are quite revolutionary," session comoderator Dr. Konstantin Nikolaou, professor of radiology at the University of Munich, said in an interview. "We’ve heard about 1.0 [mSv], so 0.2 [mSv] is great."

Still, more details are needed on exactly how the protocol works and the need to send images to the vendor for MBIR reconstruction, he said.

During a discussion of the results, Dr. Stehli said that reconstruction by the vendor typically took about 15 minutes, but Dr. Nikolau said that "it’s hard to say if that is feasible in routine clinical practice."

The ultimate test for the ultralow-dose protocol will be the clinical outcomes data, expected to be reported in 2014.

"If that proves to be robust and works in many patients and rates a good diagnostic accuracy, it would be great," Dr. Nikolau said.

The investigators would not release details on the clinical outcomes but said sensitivity and specificity for the new protocol are good.

"We believe this will have clinical applications in the near future," Dr. Stehli said in an interview.

Most patients in the study presented with chest pain (72%), and 56% were smokers, 44% had arterial hypertension, and 36% had a family history of cardiovascular disease. Their mean age was 58 years.

Dr. Stehli and her associates reported having no financial disclosures.

[email protected]

CHICAGO – Coronary computed tomography angiography with diagnostic image quality is feasible at an ultralow radiation dose of 0.2 millisievert using model-based iterative reconstruction.

This represents roughly an 80% reduction in radiation dose compared with standard coronary CT angiography, Dr. Julia Stehli said at the annual meeting of the Radiological Society of North America.

Increasing concerns about radiation exposure have prompted the use of prospective ECG triggering to reduce radiation doses from 20 mSv to 2 mSv or less. Several vendors also have developed new raw-data–based iterative reconstruction algorithms to further reduce radiation doses, but the trade-off can be increased image noise.

The model-based iterative reconstruction (MIBR) algorithm (GE Healthcare), however, has shown promising results for noise reduction, said Dr. Stehli of University Hospital Zurich. The technology, known as Veo, is already in use in the United States, Europe, and Asia for abdominal CT scans but is not yet commercially available for cardiac scans because of the added complexity of ECG triggering.

Dr. Stehli reported on the hospital’s first clinical experience with MIBR in 25 consecutive prospectively enrolled patients with suspected coronary artery disease who underwent standard low-dose coronary CT angiography (CCTA) and same-day ultralow-dose CCTA on a 64-slice CT scanner with prospective ECG triggering. Tube voltage and current were adapted to body mass index, which covered a wide range from 18.4 kg/m² to 40.2 kg/m². Contrast media volume and flow rate were adapted to body surface area. Intravenous beta-blockers were used prior to CCTA in 20 patients.

Standard CCTA was reconstructed using 30% of adaptive statistical iterative reconstruction (ASIR) according to usual hospital practice, while the ultralow-dose images were sent to the vendor for reconstruction with MIBR.

The effective radiation dose was 1.3 mSv with standard CCTA and 0.2 mSv in the ultralow-dose CCTA group (P less than .001), which is in the range reported for a postero-anterior and lateral chest X-ray, Dr. Stehli said.

A total of 100 vessels and 330 coronary artery segments were semiquantitatively assessed by two blinded, independent readers using a 4-point Likert scale, with 1 being nondiagnostic, 2 good, 3 adequate, and 4 excellent. The Kappa value for interobserver agreement of image quality was 0.8.

The average image quality score per segment was 3.3 with standard CCTA vs. 3.4 with ultralow-dose MBIR (P less than .05), she said.

Diagnostic image quality (score 2-4) was found in 319 segments (97%) and 317 segments (96%), respectively.

"These numbers are quite revolutionary," session comoderator Dr. Konstantin Nikolaou, professor of radiology at the University of Munich, said in an interview. "We’ve heard about 1.0 [mSv], so 0.2 [mSv] is great."

Still, more details are needed on exactly how the protocol works and the need to send images to the vendor for MBIR reconstruction, he said.

During a discussion of the results, Dr. Stehli said that reconstruction by the vendor typically took about 15 minutes, but Dr. Nikolau said that "it’s hard to say if that is feasible in routine clinical practice."

The ultimate test for the ultralow-dose protocol will be the clinical outcomes data, expected to be reported in 2014.

"If that proves to be robust and works in many patients and rates a good diagnostic accuracy, it would be great," Dr. Nikolau said.

The investigators would not release details on the clinical outcomes but said sensitivity and specificity for the new protocol are good.

"We believe this will have clinical applications in the near future," Dr. Stehli said in an interview.

Most patients in the study presented with chest pain (72%), and 56% were smokers, 44% had arterial hypertension, and 36% had a family history of cardiovascular disease. Their mean age was 58 years.

Dr. Stehli and her associates reported having no financial disclosures.

[email protected]

CHICAGO – Coronary computed tomography angiography with diagnostic image quality is feasible at an ultralow radiation dose of 0.2 millisievert using model-based iterative reconstruction.

This represents roughly an 80% reduction in radiation dose compared with standard coronary CT angiography, Dr. Julia Stehli said at the annual meeting of the Radiological Society of North America.

Increasing concerns about radiation exposure have prompted the use of prospective ECG triggering to reduce radiation doses from 20 mSv to 2 mSv or less. Several vendors also have developed new raw-data–based iterative reconstruction algorithms to further reduce radiation doses, but the trade-off can be increased image noise.

The model-based iterative reconstruction (MIBR) algorithm (GE Healthcare), however, has shown promising results for noise reduction, said Dr. Stehli of University Hospital Zurich. The technology, known as Veo, is already in use in the United States, Europe, and Asia for abdominal CT scans but is not yet commercially available for cardiac scans because of the added complexity of ECG triggering.

Dr. Stehli reported on the hospital’s first clinical experience with MIBR in 25 consecutive prospectively enrolled patients with suspected coronary artery disease who underwent standard low-dose coronary CT angiography (CCTA) and same-day ultralow-dose CCTA on a 64-slice CT scanner with prospective ECG triggering. Tube voltage and current were adapted to body mass index, which covered a wide range from 18.4 kg/m² to 40.2 kg/m². Contrast media volume and flow rate were adapted to body surface area. Intravenous beta-blockers were used prior to CCTA in 20 patients.

Standard CCTA was reconstructed using 30% of adaptive statistical iterative reconstruction (ASIR) according to usual hospital practice, while the ultralow-dose images were sent to the vendor for reconstruction with MIBR.

The effective radiation dose was 1.3 mSv with standard CCTA and 0.2 mSv in the ultralow-dose CCTA group (P less than .001), which is in the range reported for a postero-anterior and lateral chest X-ray, Dr. Stehli said.

A total of 100 vessels and 330 coronary artery segments were semiquantitatively assessed by two blinded, independent readers using a 4-point Likert scale, with 1 being nondiagnostic, 2 good, 3 adequate, and 4 excellent. The Kappa value for interobserver agreement of image quality was 0.8.

The average image quality score per segment was 3.3 with standard CCTA vs. 3.4 with ultralow-dose MBIR (P less than .05), she said.

Diagnostic image quality (score 2-4) was found in 319 segments (97%) and 317 segments (96%), respectively.

"These numbers are quite revolutionary," session comoderator Dr. Konstantin Nikolaou, professor of radiology at the University of Munich, said in an interview. "We’ve heard about 1.0 [mSv], so 0.2 [mSv] is great."

Still, more details are needed on exactly how the protocol works and the need to send images to the vendor for MBIR reconstruction, he said.

During a discussion of the results, Dr. Stehli said that reconstruction by the vendor typically took about 15 minutes, but Dr. Nikolau said that "it’s hard to say if that is feasible in routine clinical practice."

The ultimate test for the ultralow-dose protocol will be the clinical outcomes data, expected to be reported in 2014.

"If that proves to be robust and works in many patients and rates a good diagnostic accuracy, it would be great," Dr. Nikolau said.

The investigators would not release details on the clinical outcomes but said sensitivity and specificity for the new protocol are good.

"We believe this will have clinical applications in the near future," Dr. Stehli said in an interview.

Most patients in the study presented with chest pain (72%), and 56% were smokers, 44% had arterial hypertension, and 36% had a family history of cardiovascular disease. Their mean age was 58 years.

Dr. Stehli and her associates reported having no financial disclosures.

[email protected]

No one knows whether patients with stable ischemic heart disease and moderate or severe inducible ischemia benefit from revascularization when added to optimal medical therapy. A major, federally-funded trial named ISCHEMIA is underway to answer this question.

Main results from ISCHEMIA are still several years off, but the study has already produced an interesting finding about current cardiology practice and the way that cardiac stress-imaging studies are ordered.

Courtesy Oliver Gaemperli and Phillip A. Kaufmann, University Hospital Zurich and the Society of Nuclear Medicine and Molecular Imaging

Based on first-year enrollment data from the ISCHEMIA trial, the vast majority of both U.S. and European patients currently referred for stress-imaging assessment of ischemia have little or no inducible ischemia, Dr. Judith S. Hochman, head of the study, said during a talk at the American Heart Association’s Scientific Sessions in November.

Stable angina patients enrolled into ISCHEMIA need to have at least moderate inducible ischemia, defined as involving at least 10% of the left ventricle, in a cardiac imaging study read by a core laboratory. Since the trial began in July 2012, fewer than 700 patients had been enrolled based on imaging studies from about 15,000 patients. In the United States, about 3% of imaged patients had moderate or severe induced ischemia; the other 97% of patients referred for assessment had mild or no induced ischemia. In Europe, the rate with moderate or severe induced ischemia was slightly higher at 5%.

This observation made Dr. Hochman, a New York University cardiologist, ask why the prevalence of moderate or severe ischemia is so low in patients referred for stress imaging. She also wondered which patients with stable angina are undergoing revascularization today if so few qualify with moderate or severe inducible ischemia.

Another surprising fact she highlighted is how cardiologists manage patients found to have moderate or severe inducible ischemia. "Most of us think that all these patients with moderate to severe inducible ischemia are referred for catheterization," but that’s not what study results showed. She cited U.S. data from the mid- and late 2000s documenting that about one-third to two-thirds of these patients undergo cardiac catheterization.

This finding shows that there is "clinical equipoise" on how to manage these patients, and the ISCHEMIA trial will address that issue.

But until the results arrive in 2020, will as many stress-imaging studies continue for patients with stable angina when so many referred patients turn out to be negative for more advanced coronary disease? And, as Dr. Tracy Y. Wang, a cardiologist at Duke University, Durham, N.C., asked after hearing about the equivocal use of catheterization for patients with worse inducible ischemia: Why do physicians order these tests if they don’t intend to catheterize patients found to have moderate-to-severe inducible ischemia?

[email protected]

On Twitter @mitchelzoler

No one knows whether patients with stable ischemic heart disease and moderate or severe inducible ischemia benefit from revascularization when added to optimal medical therapy. A major, federally-funded trial named ISCHEMIA is underway to answer this question.

Main results from ISCHEMIA are still several years off, but the study has already produced an interesting finding about current cardiology practice and the way that cardiac stress-imaging studies are ordered.

Courtesy Oliver Gaemperli and Phillip A. Kaufmann, University Hospital Zurich and the Society of Nuclear Medicine and Molecular Imaging

Based on first-year enrollment data from the ISCHEMIA trial, the vast majority of both U.S. and European patients currently referred for stress-imaging assessment of ischemia have little or no inducible ischemia, Dr. Judith S. Hochman, head of the study, said during a talk at the American Heart Association’s Scientific Sessions in November.

Stable angina patients enrolled into ISCHEMIA need to have at least moderate inducible ischemia, defined as involving at least 10% of the left ventricle, in a cardiac imaging study read by a core laboratory. Since the trial began in July 2012, fewer than 700 patients had been enrolled based on imaging studies from about 15,000 patients. In the United States, about 3% of imaged patients had moderate or severe induced ischemia; the other 97% of patients referred for assessment had mild or no induced ischemia. In Europe, the rate with moderate or severe induced ischemia was slightly higher at 5%.

This observation made Dr. Hochman, a New York University cardiologist, ask why the prevalence of moderate or severe ischemia is so low in patients referred for stress imaging. She also wondered which patients with stable angina are undergoing revascularization today if so few qualify with moderate or severe inducible ischemia.

Another surprising fact she highlighted is how cardiologists manage patients found to have moderate or severe inducible ischemia. "Most of us think that all these patients with moderate to severe inducible ischemia are referred for catheterization," but that’s not what study results showed. She cited U.S. data from the mid- and late 2000s documenting that about one-third to two-thirds of these patients undergo cardiac catheterization.

This finding shows that there is "clinical equipoise" on how to manage these patients, and the ISCHEMIA trial will address that issue.

But until the results arrive in 2020, will as many stress-imaging studies continue for patients with stable angina when so many referred patients turn out to be negative for more advanced coronary disease? And, as Dr. Tracy Y. Wang, a cardiologist at Duke University, Durham, N.C., asked after hearing about the equivocal use of catheterization for patients with worse inducible ischemia: Why do physicians order these tests if they don’t intend to catheterize patients found to have moderate-to-severe inducible ischemia?

[email protected]

On Twitter @mitchelzoler

No one knows whether patients with stable ischemic heart disease and moderate or severe inducible ischemia benefit from revascularization when added to optimal medical therapy. A major, federally-funded trial named ISCHEMIA is underway to answer this question.

Main results from ISCHEMIA are still several years off, but the study has already produced an interesting finding about current cardiology practice and the way that cardiac stress-imaging studies are ordered.

Courtesy Oliver Gaemperli and Phillip A. Kaufmann, University Hospital Zurich and the Society of Nuclear Medicine and Molecular Imaging

Based on first-year enrollment data from the ISCHEMIA trial, the vast majority of both U.S. and European patients currently referred for stress-imaging assessment of ischemia have little or no inducible ischemia, Dr. Judith S. Hochman, head of the study, said during a talk at the American Heart Association’s Scientific Sessions in November.

Stable angina patients enrolled into ISCHEMIA need to have at least moderate inducible ischemia, defined as involving at least 10% of the left ventricle, in a cardiac imaging study read by a core laboratory. Since the trial began in July 2012, fewer than 700 patients had been enrolled based on imaging studies from about 15,000 patients. In the United States, about 3% of imaged patients had moderate or severe induced ischemia; the other 97% of patients referred for assessment had mild or no induced ischemia. In Europe, the rate with moderate or severe induced ischemia was slightly higher at 5%.

This observation made Dr. Hochman, a New York University cardiologist, ask why the prevalence of moderate or severe ischemia is so low in patients referred for stress imaging. She also wondered which patients with stable angina are undergoing revascularization today if so few qualify with moderate or severe inducible ischemia.

Another surprising fact she highlighted is how cardiologists manage patients found to have moderate or severe inducible ischemia. "Most of us think that all these patients with moderate to severe inducible ischemia are referred for catheterization," but that’s not what study results showed. She cited U.S. data from the mid- and late 2000s documenting that about one-third to two-thirds of these patients undergo cardiac catheterization.

This finding shows that there is "clinical equipoise" on how to manage these patients, and the ISCHEMIA trial will address that issue.

But until the results arrive in 2020, will as many stress-imaging studies continue for patients with stable angina when so many referred patients turn out to be negative for more advanced coronary disease? And, as Dr. Tracy Y. Wang, a cardiologist at Duke University, Durham, N.C., asked after hearing about the equivocal use of catheterization for patients with worse inducible ischemia: Why do physicians order these tests if they don’t intend to catheterize patients found to have moderate-to-severe inducible ischemia?

[email protected]

On Twitter @mitchelzoler

SEATTLE – Septic patients are more likely to respond to fluid therapy if their velocity time integral – a Doppler ultrasound measurement of blood flow across the left ventricular outflow tract – increases by 15% or more with a passive single-leg raise, according to a preliminary, observational study of 32 patients at New York Methodist Hospital in Brooklyn.

A passive leg raise to 45 degrees simulates a 250- to 500-cc fluid bolus. "We have found that people who don’t respond with a VTI greater than 15% have higher repeat lactate levels. Instead of giving them 2 L [of fluid] and then reassessing, maybe they’re patients you want to start on pressors right away," Dr. Andrew Balk said at the annual meeting of the American College of Emergency Physicians.

Echocardiogram machines can automatically calculate VTI. The measurement, which Dr. Balk and his associates obtained from the apical five-chamber view, is a surrogate for, and can be used to calculate, cardiac output. Poor response to fluid challenge indicates that fluids are less likely to increase cardiac output and more likely to cause fluid overload, said Dr. Balk, associate director of the clinical ultrasound division at the hospital.

The patients’ mean age was 68 years, and those with valvular pathology and atrial fibrillation were excluded from the study.

The group’s mean baseline VTI was 22 cm (range, 15-29 cm), which leg raises raised to a mean of 26 cm (18-34 cm), an increase of about 18% (4%-36%). A subsequent 2-L normal saline challenge increased VTI to a mean of 33 cm.

The mean baseline lactate level was 3.2 mmol/L (1.2-5.2 mmol/L), and 2 mmol/L (1-3 mmol/L) after the 2-L challenge. The percent change in VTI correlated significantly with the percent change in serum lactate levels. "Below-average responsiveness to the initial small fluid bolus was associated with a higher repeat lactate value, ... which suggests an inverse relationship between a patient’s fluid responsiveness as observed by the change in VTI and the severity of sepsis," the researchers concluded.

The VTI/leg-raise approach looks promising as a possible quick bedside marker that identifies patients who need aggressive treatment, without the need for central line measurements, Dr. Balk said. "The quickest initial fluid bolus you can get is a passive leg raise. You can watch for changes" in real time, and don’t have to move the probe from the point of maximum impact.

Dr. Balk reported having no disclosures.

Dr. Steven Q. Simpson commented: The search for noninvasive measures of or predictors for volume responsiveness in septic patients continues. VTI is the integral of velocity and time, i.e., the distance a small blood bolus travels. When multiplied by cross-sectional area of the aortic outflow tract, this would result in stroke volume. Since one would not expect the cross-sectional area to change significantly after a fluid bolus, alterations in VTI should reflect alterations in stroke volume. While promising, this technique is not as easy as the authors make it sound

and is operator dependent, even though the machine does the calculating. The incident angle of the probe must remain constant during the leg raise (at least 90 seconds). The user must know whether valve pathology or LV impairment are present and, if so, the degree. Massively volume depleted patients may fail to respond adequately to a passive leg raise.

One would be remiss to rely on this small study, which does not report sensitivity or specificity, to establish a reliable percent increase for predicting lactate response or to guide fluid therapy. However, this research is certainly aimed in the right direction.

Dr. Steven Q. Simpson is professor of medicine and director of fellowship training in the pulmonary disease and critical care medicine division at the University of Kansas Medical Center, Kansas City.

[email protected]

SEATTLE – Septic patients are more likely to respond to fluid therapy if their velocity time integral – a Doppler ultrasound measurement of blood flow across the left ventricular outflow tract – increases by 15% or more with a passive single-leg raise, according to a preliminary, observational study of 32 patients at New York Methodist Hospital in Brooklyn.

A passive leg raise to 45 degrees simulates a 250- to 500-cc fluid bolus. "We have found that people who don’t respond with a VTI greater than 15% have higher repeat lactate levels. Instead of giving them 2 L [of fluid] and then reassessing, maybe they’re patients you want to start on pressors right away," Dr. Andrew Balk said at the annual meeting of the American College of Emergency Physicians.

Echocardiogram machines can automatically calculate VTI. The measurement, which Dr. Balk and his associates obtained from the apical five-chamber view, is a surrogate for, and can be used to calculate, cardiac output. Poor response to fluid challenge indicates that fluids are less likely to increase cardiac output and more likely to cause fluid overload, said Dr. Balk, associate director of the clinical ultrasound division at the hospital.

The patients’ mean age was 68 years, and those with valvular pathology and atrial fibrillation were excluded from the study.

The group’s mean baseline VTI was 22 cm (range, 15-29 cm), which leg raises raised to a mean of 26 cm (18-34 cm), an increase of about 18% (4%-36%). A subsequent 2-L normal saline challenge increased VTI to a mean of 33 cm.

The mean baseline lactate level was 3.2 mmol/L (1.2-5.2 mmol/L), and 2 mmol/L (1-3 mmol/L) after the 2-L challenge. The percent change in VTI correlated significantly with the percent change in serum lactate levels. "Below-average responsiveness to the initial small fluid bolus was associated with a higher repeat lactate value, ... which suggests an inverse relationship between a patient’s fluid responsiveness as observed by the change in VTI and the severity of sepsis," the researchers concluded.

The VTI/leg-raise approach looks promising as a possible quick bedside marker that identifies patients who need aggressive treatment, without the need for central line measurements, Dr. Balk said. "The quickest initial fluid bolus you can get is a passive leg raise. You can watch for changes" in real time, and don’t have to move the probe from the point of maximum impact.

Dr. Balk reported having no disclosures.

Dr. Steven Q. Simpson commented: The search for noninvasive measures of or predictors for volume responsiveness in septic patients continues. VTI is the integral of velocity and time, i.e., the distance a small blood bolus travels. When multiplied by cross-sectional area of the aortic outflow tract, this would result in stroke volume. Since one would not expect the cross-sectional area to change significantly after a fluid bolus, alterations in VTI should reflect alterations in stroke volume. While promising, this technique is not as easy as the authors make it sound

and is operator dependent, even though the machine does the calculating. The incident angle of the probe must remain constant during the leg raise (at least 90 seconds). The user must know whether valve pathology or LV impairment are present and, if so, the degree. Massively volume depleted patients may fail to respond adequately to a passive leg raise.

One would be remiss to rely on this small study, which does not report sensitivity or specificity, to establish a reliable percent increase for predicting lactate response or to guide fluid therapy. However, this research is certainly aimed in the right direction.

Dr. Steven Q. Simpson is professor of medicine and director of fellowship training in the pulmonary disease and critical care medicine division at the University of Kansas Medical Center, Kansas City.

[email protected]

SEATTLE – Septic patients are more likely to respond to fluid therapy if their velocity time integral – a Doppler ultrasound measurement of blood flow across the left ventricular outflow tract – increases by 15% or more with a passive single-leg raise, according to a preliminary, observational study of 32 patients at New York Methodist Hospital in Brooklyn.

A passive leg raise to 45 degrees simulates a 250- to 500-cc fluid bolus. "We have found that people who don’t respond with a VTI greater than 15% have higher repeat lactate levels. Instead of giving them 2 L [of fluid] and then reassessing, maybe they’re patients you want to start on pressors right away," Dr. Andrew Balk said at the annual meeting of the American College of Emergency Physicians.

Echocardiogram machines can automatically calculate VTI. The measurement, which Dr. Balk and his associates obtained from the apical five-chamber view, is a surrogate for, and can be used to calculate, cardiac output. Poor response to fluid challenge indicates that fluids are less likely to increase cardiac output and more likely to cause fluid overload, said Dr. Balk, associate director of the clinical ultrasound division at the hospital.

The patients’ mean age was 68 years, and those with valvular pathology and atrial fibrillation were excluded from the study.

The group’s mean baseline VTI was 22 cm (range, 15-29 cm), which leg raises raised to a mean of 26 cm (18-34 cm), an increase of about 18% (4%-36%). A subsequent 2-L normal saline challenge increased VTI to a mean of 33 cm.

The mean baseline lactate level was 3.2 mmol/L (1.2-5.2 mmol/L), and 2 mmol/L (1-3 mmol/L) after the 2-L challenge. The percent change in VTI correlated significantly with the percent change in serum lactate levels. "Below-average responsiveness to the initial small fluid bolus was associated with a higher repeat lactate value, ... which suggests an inverse relationship between a patient’s fluid responsiveness as observed by the change in VTI and the severity of sepsis," the researchers concluded.

The VTI/leg-raise approach looks promising as a possible quick bedside marker that identifies patients who need aggressive treatment, without the need for central line measurements, Dr. Balk said. "The quickest initial fluid bolus you can get is a passive leg raise. You can watch for changes" in real time, and don’t have to move the probe from the point of maximum impact.

Dr. Balk reported having no disclosures.

Dr. Steven Q. Simpson commented: The search for noninvasive measures of or predictors for volume responsiveness in septic patients continues. VTI is the integral of velocity and time, i.e., the distance a small blood bolus travels. When multiplied by cross-sectional area of the aortic outflow tract, this would result in stroke volume. Since one would not expect the cross-sectional area to change significantly after a fluid bolus, alterations in VTI should reflect alterations in stroke volume. While promising, this technique is not as easy as the authors make it sound

and is operator dependent, even though the machine does the calculating. The incident angle of the probe must remain constant during the leg raise (at least 90 seconds). The user must know whether valve pathology or LV impairment are present and, if so, the degree. Massively volume depleted patients may fail to respond adequately to a passive leg raise.

One would be remiss to rely on this small study, which does not report sensitivity or specificity, to establish a reliable percent increase for predicting lactate response or to guide fluid therapy. However, this research is certainly aimed in the right direction.

Dr. Steven Q. Simpson is professor of medicine and director of fellowship training in the pulmonary disease and critical care medicine division at the University of Kansas Medical Center, Kansas City.

[email protected]

The idiom “penny wise, pound foolish” certainly applies in this report of 2 cases of missed bone tumors that were present but not recognized on preoperative imaging prior to placement of patient-specific knee arthroplasties. The case report appeared in the December 2013 issue of The American Journal of Orthopedics. The term “non-diagnostic imaging,” itself a paradox, used in the context of preoperative imaging performed solely for the purpose of component templating for patient-specific instrumentation (PSI) and not intended to be diagnostic in purpose, would be anathematic to most radiologists and should be discarded as a concept.

Bearing in mind the costs incurred by the patient undergoing a total knee arthroplasty (TKA), such as professional consultation, preoperative magnetic resonance imaging, customized manufacture of the components, surgery and associated costs, and postoperative rehabilitation, the fee for a formal report by a musculoskeletal radiologist is comparatively minuscule. As correctly pointed out by the authors, the price associated with bypassing any assessment and missing malignant disease is far greater.

It is well recognized that unreported radiologic examinations can lead to misdiagnosis, compromised patient care, and liability concerns. As PSI is relatively new and has good potential to increase the accuracy, precision and efficiency of TKA, it is even more vital that this promising technology not be marred by disrepute due to possible devastating outcomes resulting from lack of a radiologic report. From the professional point of view of a radiologist, the issuance of a formal report is part and parcel of any radiological examination. I would argue that obtaining radiologic images without an accompanying report constitutes an incomplete study, and will not be in the best interest of patients.

Let the lessons learned from these 2 cases be a springboard to establish protocols for proper utilization of technologies involved in PSI for TKA and other orthopedic procedures. It is imperative to put into place mandatory reporting of all diagnostic images obtained for preoperative evaluation, particularly those that are meant to be sent directly to implant manufacturers for component design.

Menge TJ, Hartley KG, Holt GE. Patient-Specific Imaging and Missed Tumors: A Catastrophic Outcome. Am J Orthop. 2013;42(12):553-556.

The idiom “penny wise, pound foolish” certainly applies in this report of 2 cases of missed bone tumors that were present but not recognized on preoperative imaging prior to placement of patient-specific knee arthroplasties. The case report appeared in the December 2013 issue of The American Journal of Orthopedics. The term “non-diagnostic imaging,” itself a paradox, used in the context of preoperative imaging performed solely for the purpose of component templating for patient-specific instrumentation (PSI) and not intended to be diagnostic in purpose, would be anathematic to most radiologists and should be discarded as a concept.

Bearing in mind the costs incurred by the patient undergoing a total knee arthroplasty (TKA), such as professional consultation, preoperative magnetic resonance imaging, customized manufacture of the components, surgery and associated costs, and postoperative rehabilitation, the fee for a formal report by a musculoskeletal radiologist is comparatively minuscule. As correctly pointed out by the authors, the price associated with bypassing any assessment and missing malignant disease is far greater.

It is well recognized that unreported radiologic examinations can lead to misdiagnosis, compromised patient care, and liability concerns. As PSI is relatively new and has good potential to increase the accuracy, precision and efficiency of TKA, it is even more vital that this promising technology not be marred by disrepute due to possible devastating outcomes resulting from lack of a radiologic report. From the professional point of view of a radiologist, the issuance of a formal report is part and parcel of any radiological examination. I would argue that obtaining radiologic images without an accompanying report constitutes an incomplete study, and will not be in the best interest of patients.

Let the lessons learned from these 2 cases be a springboard to establish protocols for proper utilization of technologies involved in PSI for TKA and other orthopedic procedures. It is imperative to put into place mandatory reporting of all diagnostic images obtained for preoperative evaluation, particularly those that are meant to be sent directly to implant manufacturers for component design.

Menge TJ, Hartley KG, Holt GE. Patient-Specific Imaging and Missed Tumors: A Catastrophic Outcome. Am J Orthop. 2013;42(12):553-556.

The idiom “penny wise, pound foolish” certainly applies in this report of 2 cases of missed bone tumors that were present but not recognized on preoperative imaging prior to placement of patient-specific knee arthroplasties. The case report appeared in the December 2013 issue of The American Journal of Orthopedics. The term “non-diagnostic imaging,” itself a paradox, used in the context of preoperative imaging performed solely for the purpose of component templating for patient-specific instrumentation (PSI) and not intended to be diagnostic in purpose, would be anathematic to most radiologists and should be discarded as a concept.

Bearing in mind the costs incurred by the patient undergoing a total knee arthroplasty (TKA), such as professional consultation, preoperative magnetic resonance imaging, customized manufacture of the components, surgery and associated costs, and postoperative rehabilitation, the fee for a formal report by a musculoskeletal radiologist is comparatively minuscule. As correctly pointed out by the authors, the price associated with bypassing any assessment and missing malignant disease is far greater.

It is well recognized that unreported radiologic examinations can lead to misdiagnosis, compromised patient care, and liability concerns. As PSI is relatively new and has good potential to increase the accuracy, precision and efficiency of TKA, it is even more vital that this promising technology not be marred by disrepute due to possible devastating outcomes resulting from lack of a radiologic report. From the professional point of view of a radiologist, the issuance of a formal report is part and parcel of any radiological examination. I would argue that obtaining radiologic images without an accompanying report constitutes an incomplete study, and will not be in the best interest of patients.

Let the lessons learned from these 2 cases be a springboard to establish protocols for proper utilization of technologies involved in PSI for TKA and other orthopedic procedures. It is imperative to put into place mandatory reporting of all diagnostic images obtained for preoperative evaluation, particularly those that are meant to be sent directly to implant manufacturers for component design.

Menge TJ, Hartley KG, Holt GE. Patient-Specific Imaging and Missed Tumors: A Catastrophic Outcome. Am J Orthop. 2013;42(12):553-556.

The English expression, “a pain in the neck” is said to have originated in the early 1900s as a euphemism for the less polite phrase, “a pain in the ass.”¹ While one might wonder how the expressions of such disparate discomforts came to be idiomatically equivalent, the focus of this article is on etiology of the former. All wryness aside, since most ED presentations of neck pain are musculoskeletal in origin, one may easily fail to consider the myriad of less common, but possibly serious, causes.

Pain can originate from any part of the neck and occur as a result of inflammation (eg, infections and arthritides), vascular pathology (eg, cervical artery dissection [CAD]), spaceoccupying lesions (eg, hematomas, cysts, tumors), or even as referred pain from noncervical sources (eg, heart, diaphragm, lung apex). Any lesion encroaching on the limited space of the neck can quickly compromise the airway, compress nerves, or inhibit blood flow to the brain; therefore, knowledge of the causes of such conditions is critical. This article reviews some of the less common and generally atraumatic etiologies of nontraumatic neck pain of which the emergency physician should be familiar.

Vascular Disorders
Vascular-associated neck pain can originate from vessels within the neck or represent referred pain from a more distant structure. In both cases, however, the potential for morbidity is high and the need for consideration and timely recognition crucial.

Cervical Artery Dissection
The typical initial presenting symptom of CAD—ie, internal CAD (ICAD) or vertebral artery dissection (VAD)—is severe pain in the ipsilateral neck and/or head. Onset of pain may be sudden or gradual.² CAD occurs in an estimated 2 or 3 of every 100,000 people per year, mostly in patients between ages 20 and 40 years, and it is considered the most common cause of stroke in patients younger than age 45 years.² The pain associated with CAD generally follows trauma. While the precipitating trauma can be a major blunt or penetrating one, it is often caused by something seemingly trivial, such as “trauma” associated with coughing, painting a ceiling, yoga, or (classically and notoriously) chiropractic manipulation.³ There is frequently some rotational component to CAD-associated trauma,⁴ though dissection may occur spontaneously.⁵

The typical triad of symptoms is ipsilateral neck and/or head pain, partial Horner’s syndrome (ptosis and miosis without anhidrosis), and signs of cerebral ischemia. However, patients do not always present with all three of these symptoms, which can complicate the diagnosis. For example, in some patients, neck pain is the sole presenting symptom and can mimic the musculoskeletal pain expected from the mechanical strain that precipitated the dissection.⁶ In addition, partial Horner’s syndrome occurs in only 50% of cases, and ischemic symptoms might not present for hours to weeks after the onset of neck pain.⁶

In almost all cases of CAD, initial symptoms are otherwise unexplained pain described as a constant, steady aching. ⁷ Since cervical arteries are heavily invested with pain fibers,⁸ an intimal tear with dissecting intramural hematoma provokes pain. Pain associated with VAD is usually severe, unilateral, posterior neck, and/or occipital, while ICAD-associated pain is ipsilateral, anterolateral neck, head, and/or face. It is important to note that head or neck pain caused by a dissection normally precedes the ischemic manifestation as opposed to the more common stroke, in which the ischemia precedes or is simultaneous with the accompanying headache.⁹

Ischemic neurological symptoms can arise from stenosis of the arterial lumen, secondary to an expanding intramural hematoma; a luminal thrombus developing at the intimal defect; or an embolization accompanied by ipsilateral Horner’s syndrome, any cranial nerve abnormality, or followed by cerebral or ocular ischemic symptoms (even if transient). A diagnosis is usually made through vascular ultrasound (Figure 1) and confirmed with computed tomography angiography (CTA) or magnetic resonance angiography. When requesting a CTA of the neck, the emergency physician should specifically make note of suspected CAD in the order. Immediate treatment includes a cervical collar and neurosurgical consultation even though treatment is essentially medical and surgery is rarely required. Anticoagulation therapy is routinely initiated to prevent thrombus propagation or embolization (unless there is brain hemorrhage). Antiplatelet therapy may be equally efficacious, ¹⁰ and can be initiated upon suspicions of CAD and while confirmatory studies are in progress. The prognosis for extracranial dissections is generally good.

Cervical Epidural Hematoma Cervical (spinal) epidural hematoma is an uncommon but potentially catastrophic event that can lead to permanent neurological deficits and death from respiratory failure. It presents as sudden and severe local neck pain with rapid development of radicular pain at the corresponding dermatomes. Motor and sensory deficits follow within minutes to days.12,13 Bleeding can occur spontaneously or secondary to trauma, surgery, or coagulopathy (which itself may be pathological—eg, hemophilia or iatrogenic in origin).14,15 Untreated, progressive cord compression can lead to permanent neurological deficits and death from respiratory failure. In the patient with acute neurological deficits, immediate correction of coagulation issues is required before decompressive surgery.

Diagnosis of cervical epidural hematoma is complicated by the rarity of the event and the lack of specific symptoms. When trauma is involved, cervical disc or nerve root injury is a more likely cause of sudden onset of neck pain, with rapid development of a radicular component. However, when symptoms occur following minor exertion (eg, sneezing, coitus, coughing) and in the presence of risk factors such as hematologic disorders, pregnancy, rheumatologic disorders, or liver dysfunction, epidural hematoma must be considered.¹⁶ Emergent magnetic resonance imaging (MRI) is the modality of choice for detecting this condition (Figure 2).

Coronary Ischemia Angina pectoris secondary to coronary ischemia is described as retrosternal “heaviness” or pressure, which may spread to either or both arms, the neck, or jaw. Pathology originating in the neck can be experienced as chest pain and may confound the diagnosis. Because cervical nerve roots C4-C8 contribute to the innervation of the anterior chest wall, irritation of any one of these nerves secondary to neck pathology can mimic true angina.17,18 Conversely, the likelihood that the only pain caused by coronary ischemia might be felt in the neck is low, but possible— especially in women.19,20 Coronary ischemia should be considered in patients with cardiac risk factors but no other obvious etiology for neck pain.21

Secondary Infection
Since emergency physicians are accustomed to dealing with infection, it is hard to imagine that we could fail to recognize infection as the etiology in a patient with a chief complaint of neck pain. Diagnosis in such cases is complicated by the anatomical location of deep neck-space infections, which limits the usefulness of standard physical examination. These sites are difficult to palpate and often impossible to visualize because they are covered with noninfected tissue. Unless specifically considered in the differential, more obscure causes of neck pain associated with infection may be missed, including retropharyngeal abscess, epiglottitis, Ludwig’s angina, vertebral osteomyelitis and discitis, cervical epidural abscess, and Lemierre’s syndrome.

Epiglottitis
Epiglottitis is inflammation of the epiglottis and adjacent supraglottic structures including the pharynx, uvula, and base of the tongue. The first recorded case is thought to have been that of George Washington, who is believed to have died from this disease.²² The high mortality rate (7% to 20% in the adult population) is a direct result of airway obstruction from inflammatory edema of the epiglottis and adjacent tissues.

Epiglottitis was originally considered a childhood disease; however, the widespread use of Haemophilus influenza vaccination has resulted in a decline in pediatric incidence. Most cases are now seen in adults (mean age of 46 years).^23,24

Bacterial infection, especially from the genera Hemophilus, Streptococcus, Staphylococcus, and Klebsiella, is by far the most frequent cause of acute epiglottitis; viral and fungal-associated infections are rare. Thermal injury from swallowing hot foods or liquids, and even from inhaling crack cocaine,²⁵ also has been implicated.

Clinical presentations of epiglottitis differ between children and adults. While children are typically dyspneic, drooling, stridorous and febrile, adults tend to present with a milder form of the disease and have painful swallowing, sore throat, and a muffled voice. In both children and adults, the larynx and upper trachea are tender to light palpation at the anterior neck.26 Although sore throat and odynophagia are more often symptoms of pharyngitis, suspicion should be aroused when pain is severe and/or there is dyspnea, severe pain with an unremarkable oropharynx examination, or anterior neck tenderness. When present, muffled voice and stridor indicate greater potential for airway compromise.27 In cases of significant airway obstruction, patients may assume the “tripod position,” leaning forward with neck extended and mouth open—panting. Since soft-tissue lateral neck radiographs are about 90% sensitive and specific for epiglottitis, a normalappearing film cannot reliably exclude the diagnosis.28 Evaluation for the classic “thumb sign” of epiglottic swelling27 (Figure 3) should be combined with the newly described “vallecula sign” for greatest accuracy.29 The vallecula sign is described as the partial or complete obliteration of a well-defined linear air pocket between the base of the tongue and the epiglottis seen on a closed mouth lateral neck X-ray.

Although CT is a useful modality for detecting epiglottic, peritonsillar, or deep neck space abscess, there are risks to patients with airway compromise; moreover, placing patients in a supine position for the study increases the likelihood of respiratory distress. Despite these risks, when indicated, CT is useful in differentiating these abscesses from similarly presenting entities such as lingual tonsillitis and upper airway foreign body.

Direct visualization via flexible oral or nasolaryngoscopy is the diagnostic gold standard but may be deferred in a stable patient. When absolutely indicated, it must be performed with caution, ideally by an anesthesiologist/otolaryngologist in a controlled setting, lest it precipitate further obstruction. Through the use of fiber optics, the need for emergent intubation can be more directly assessed and, if necessary, performed by “tube-over-scope” technique. In the ED, standby equipment for intubation and cricothyrotomy/needle cricothyrotomy should be immediately available and ready in the event of rapid deterioration, at the same time as intravenous (IV) infusion of third-generation cephalosporin or ampicillin/sulbactam, and methicillin-resistant Staphylococcus aureus (MRSA) coverage. Though the rationale for empirical use of antibiotics is evident, the role of corticosteroids and of nebulized racemic epinephrine is controversial.

Death, airway obstruction, epiglottic abscess, necrotizing epiglottitis, and secondary infections (eg, pneumonia, cervical adenitis, septic arthritis, meningitis) are the potential complications that make this source of neck pain one not to be missed. If epiglottitis is suspected, the patient must be admitted to an intensive care setting.

Retropharyngeal Abscess
The retropharyngeal space, immediately behind the posterior pharynx and esophagus, extends from the base of the skull to the mediastinum. It lies anterior to the deep cervical fascia and is bound laterally by the carotid sheaths.30 Because it is fused down the midline, abscesses in this area tend to be unilateral. The space cannot be directly assessed by physical examination, and infections in this area are rare. Timely diagnosis demands consideration of retropharyngeal abscess in patients presenting with fever, neck stiffness, and sore throat. The potential for serious morbidity and mortality is related to the host of vital structures immediately adjacent to the retropharyngeal space. Complications include mediastinitis, carotid artery erosion, jugular vein thrombosis, pericarditis, epidural abscess, sepsis, and airway compromise.

Most cases are typically observed in children younger than age 6 years. In this pediatric population, the retropharyngeal space has two parallel chains of lymph nodes draining the nose, sinuses, and pharynx; retropharyngeal abscesses usually occur as a suppurative extension from infections of these upper airway structures structures. Penetrating trauma, eg, from objects held in the mouth, is another possible cause. These nodes atrophy around 6 years of age; thereafter, the main cause of retropharyngeal abscess is purulent extension of an adjacent (frequently odontogenic) infection or posterior pharyngeal trauma (eg, from a fish bone or instrumentation).³¹ As befits its origin with oral flora, cultures are almost always polymicrobial (eg, Streptococci viridans and pyogenes, Staphylococcus, H influenza, Klebsiella, anaerobes).

Although retropharyngeal abscess is considered a disease of childhood, like epiglottitis, its incidence in adults is increasing. ³² Presenting symptoms are signs of respiratory distress, such as wheezing, stridor, and drooling with impending airway obstruction from the expanding posterior pharyngeal mass. Late signs of the illness are respiratory failure due to airway obstruction and septic shock, but an astute clinician should recognize the entity long before these symptoms present. Early symptoms include fever, sore throat, odynophagia, and neck pain and stiffness (typically manifesting as a reluctance to turn the neck).³³ Patients may also complain of feeling a lump in the throat or pain in the posterior neck or shoulder with swallowing.³⁴ Ninety-seven percent of pediatric patients present with neck pain,³² which could manifest dramatically as torticollis. Most likely, a child will have a subtle reluctance to move his or her neck during the course of the physical examination. In addition, there may be posterior pharyngeal edema and/or a visible unilateral posterior pharyngeal bulge, cervical adenopathy, and a “croupy” cry or cough resembling a duck’s quack—the “cri du canard.”³⁵ Definitive diagnosis is made using X-ray and/or CT. A lateral soft-tissue neck X-ray will demonstrate widening of the prevertebral soft tissues. CT with contrast provides a more definitive diagnosis, and is also useful to differentiate abscess (ie, a hypodense lesion with ring enhancement) from cellulitis.

Regarding treatment, empiric IV antibiotics must be started immediately and may alone prevent progression if the diagnosis is made before cellulitis has progressed to abscess. Intravenous clindamycin is a reasonable first-line antibiotic; other suggested drugs include a penicillin/ beta lactamase inhibitor, penicillin G plus metronidazole, and cefoxitin.36 Airway protection is mandatory, and an otolaryngologist should be consulted early. Because of the potential for sudden airway deterioration, the emergency physician must be prepared to establish a surgical airway.

Ludwig’s Angina
Ludwig’s angina derives its name from the German physician Wilhelm Friedrich von Ludwig, who first described this deadly, rapidly progressive, fascial space/ connective tissue gangrenous cellulitis of the floor of the mouth and adjoining neck in 1836. In a curious twist of fate, it is believed that Dr Ludwig died from this very disease that bears his name.³⁷

Ninety percent of cases of Ludwig’s angina are odontogenic, often due to periapical abscesses. This condition may result secondary to any oral or parapharyngeal infection that spreads by continuity from the submandibular space into the contiguous sublingual and submental spaces. The potential for airway obstruction comes from elevation and displacement of the tongue, resulting in a mortality rate greater than 50% if untreated. Causative organisms mirror normal, polymicrobial oral flora and include Staphylococcus, Streptococcus, Fusobacterium, and Bacteroides.^38,23

Diagnosis of Ludwig’s angina is primarily clinical. Neck pain and swelling, dental pain, dysphagia, malaise, and fever, along with a protruding or elevated tongue, are typical. Submandibular swelling, which is seen in 95% of patients, develops in advanced cases into an intense “woody” induration above the hyoid bone that portends the impending airway crisis.³⁹ If the patient is sufficiently clinically stable and able to lie flat, definitive diagnosis can be made with a contrastenhanced, soft-tissue neck CT (Figure 4), which can also evaluate for a drainable abscess, soft-tissue gas, and mediastinal extension; this modality can also define the extent of soft-tissue swelling and airway patency.

Airway management is the primary consideration because of its potential for rapid deterioration. Traditional management has been aggressive and surgical, with the standard being early tracheostomy. More recent reports have encouraged more conservative management when possible.40 Impending or actual airway compromise, as manifest by significant trismus, inability to flex the neck without compromising the airway, inability to protrude the tongue, or actual resting dyspnea demand that a surgical airway be readied at bedside until fiber optic nasotracheal intubation is secured.

Antibiotics must be given early and include coverage for gram-positive, gramnegative, and anaerobic organisms. Intravenous metronidazole and penicillin (cefazolin or clindamycin if patient has an allergy to penicillin) are commonly prescribed.^38,23 Although controversial, administration of IV dexamethasone (8 mg to 12 mg) and nebulized epinephrine (1:1000, 1 mL diluted to 5 mL with normal saline) to reduce edema has been advocated. ⁴¹

Lemierre’s Syndrome Lemierre’s syndrome, septic thrombophlebitis of the internal jugular vein, was first described in 1936 by André Lemierre, who published a series of cases of previously healthy young adults in whom oropharyngeal infections were followed by “anaerobic postanginal septicaemias.”42 Most of these patients presented with sore throat (referred to as “angina” in “old skool” speak) and worsening pain and tenderness at the anterolateral neck, with pulmonary symptoms manifesting several days to 2 weeks later. The causative organism, Fusobacterium necrophorum, is a gram-negative anaerobe that is part of the normal commensal oropharyngeal flora. It invades the internal jugular (IJ) vein via the lateral pharyngeal space and releases a hemagglutinin that promotes thrombus formation in the IJ and, ultimately, metastatic septic emboli. These emboli typically invade the lungs and cause multiple nodular infiltrates and small pleural effusions. Unfortunately, as each case is unique, diagnosis is often delayed. Septic emboli can migrate to other sites and cause arthritis (hip, knee, shoulder, sacroiliac, and other joints), osteomyelitis, young adult with a history of recent sore throat and fever who subsequently developed neck pain and tenderness (with or without swelling) over the IJ, rigors, pulmonary infiltrates, and possibly other signs of septic emboli.

Doppler ultrasound or CT will show IJ thrombosis43 (Figure 5). Purulent discharge, if obtained, has a characteristic foul smell that has been likened to “limburger or overripe Camembert cheese.”44 Treatment is with high-dose IV penicillin and metronidazole or with clindamycin as single coverage. Heparin could potentially aid in dissemination of emboli, but it is used only when there is retrograde propagation of clot to the cavernous sinus.

With the routine antibiotic treatment of pharyngitis in the 1960s and 1970s, cases of Lemierre’s syndrome became so rare that it was referred to as the “forgotten disease.”⁴⁵ Unfortunately, its incidence has increased over the past few years.⁴³ It is unclear whether this rise is due to increasing antibiotic resistance or to an increasing resistance of clinicians to use antibiotics for “sore throats.”

Cervical Spinal Infections
Vertebral osteomyelitis, discitis, and spinal epidural abscess are rare in developed countries. Most cases stem from hematogenous seeding, skin abscesses, and urinary tract infections but can also originate from a host of other sites, including penetrating trauma and invasive spinal procedures (eg, lumbar punctures, epidural injections). ^46,47 Cervical spine infections are associated with immune-compromising situations or conditions (eg, IV drug use, diabetes mellitus, malignancy, acquired immunodeficiency syndrome, renal insufficiency, long-term use of systemic corticosteroids).

All three of these conditions present similarly, often as localized neck pain that grows more intense over a period of days to weeks and worsens with neck movement. Neurological signs ordinarily appear late in the course of the illness. Fever is a classic symptom but is not always present.⁴⁸ There is usually tenderness over the involved spinous process. The development of motor or sensory loss suggests formation of an abscess,⁴⁹ which can rapidly lead to further compressive symptoms and sepsis.

Leukocytosis may be absent but erythrocyte sedimentation rate and C-reactive protein are often elevated. A CT scan with contrast is frequently required for diagnosis, though when available, MRI with IV gadolinium is the test of choice (Figure 6). Most cases are caused by S aureus, but antibiotic coverage for gram-positive organisms (including MRSA), gram-negative organisms, and anaerobes should be started as soon as blood cultures are drawn. Neurosurgery should be consulted emergently since, with cervical epidural abscess, neurological deterioration—even to the point of total paralysis—can develop in a matter of hours.⁵⁰

Conclusion
Although most patients presenting to the ED with neck pain are musculoskeletal and associated with a traumatic event, other infrequent but potentially serious atraumatic causes may be present. Based on a patient’s symptoms, emergency physicians should also consider these conditions in the differential diagnosis to ensure rapid treatment to prevent further complications.

The English expression, “a pain in the neck” is said to have originated in the early 1900s as a euphemism for the less polite phrase, “a pain in the ass.”¹ While one might wonder how the expressions of such disparate discomforts came to be idiomatically equivalent, the focus of this article is on etiology of the former. All wryness aside, since most ED presentations of neck pain are musculoskeletal in origin, one may easily fail to consider the myriad of less common, but possibly serious, causes.

Pain can originate from any part of the neck and occur as a result of inflammation (eg, infections and arthritides), vascular pathology (eg, cervical artery dissection [CAD]), spaceoccupying lesions (eg, hematomas, cysts, tumors), or even as referred pain from noncervical sources (eg, heart, diaphragm, lung apex). Any lesion encroaching on the limited space of the neck can quickly compromise the airway, compress nerves, or inhibit blood flow to the brain; therefore, knowledge of the causes of such conditions is critical. This article reviews some of the less common and generally atraumatic etiologies of nontraumatic neck pain of which the emergency physician should be familiar.

Vascular Disorders
Vascular-associated neck pain can originate from vessels within the neck or represent referred pain from a more distant structure. In both cases, however, the potential for morbidity is high and the need for consideration and timely recognition crucial.

Cervical Artery Dissection
The typical initial presenting symptom of CAD—ie, internal CAD (ICAD) or vertebral artery dissection (VAD)—is severe pain in the ipsilateral neck and/or head. Onset of pain may be sudden or gradual.² CAD occurs in an estimated 2 or 3 of every 100,000 people per year, mostly in patients between ages 20 and 40 years, and it is considered the most common cause of stroke in patients younger than age 45 years.² The pain associated with CAD generally follows trauma. While the precipitating trauma can be a major blunt or penetrating one, it is often caused by something seemingly trivial, such as “trauma” associated with coughing, painting a ceiling, yoga, or (classically and notoriously) chiropractic manipulation.³ There is frequently some rotational component to CAD-associated trauma,⁴ though dissection may occur spontaneously.⁵

The typical triad of symptoms is ipsilateral neck and/or head pain, partial Horner’s syndrome (ptosis and miosis without anhidrosis), and signs of cerebral ischemia. However, patients do not always present with all three of these symptoms, which can complicate the diagnosis. For example, in some patients, neck pain is the sole presenting symptom and can mimic the musculoskeletal pain expected from the mechanical strain that precipitated the dissection.⁶ In addition, partial Horner’s syndrome occurs in only 50% of cases, and ischemic symptoms might not present for hours to weeks after the onset of neck pain.⁶

In almost all cases of CAD, initial symptoms are otherwise unexplained pain described as a constant, steady aching. ⁷ Since cervical arteries are heavily invested with pain fibers,⁸ an intimal tear with dissecting intramural hematoma provokes pain. Pain associated with VAD is usually severe, unilateral, posterior neck, and/or occipital, while ICAD-associated pain is ipsilateral, anterolateral neck, head, and/or face. It is important to note that head or neck pain caused by a dissection normally precedes the ischemic manifestation as opposed to the more common stroke, in which the ischemia precedes or is simultaneous with the accompanying headache.⁹

Ischemic neurological symptoms can arise from stenosis of the arterial lumen, secondary to an expanding intramural hematoma; a luminal thrombus developing at the intimal defect; or an embolization accompanied by ipsilateral Horner’s syndrome, any cranial nerve abnormality, or followed by cerebral or ocular ischemic symptoms (even if transient). A diagnosis is usually made through vascular ultrasound (Figure 1) and confirmed with computed tomography angiography (CTA) or magnetic resonance angiography. When requesting a CTA of the neck, the emergency physician should specifically make note of suspected CAD in the order. Immediate treatment includes a cervical collar and neurosurgical consultation even though treatment is essentially medical and surgery is rarely required. Anticoagulation therapy is routinely initiated to prevent thrombus propagation or embolization (unless there is brain hemorrhage). Antiplatelet therapy may be equally efficacious, ¹⁰ and can be initiated upon suspicions of CAD and while confirmatory studies are in progress. The prognosis for extracranial dissections is generally good.

Cervical Epidural Hematoma Cervical (spinal) epidural hematoma is an uncommon but potentially catastrophic event that can lead to permanent neurological deficits and death from respiratory failure. It presents as sudden and severe local neck pain with rapid development of radicular pain at the corresponding dermatomes. Motor and sensory deficits follow within minutes to days.12,13 Bleeding can occur spontaneously or secondary to trauma, surgery, or coagulopathy (which itself may be pathological—eg, hemophilia or iatrogenic in origin).14,15 Untreated, progressive cord compression can lead to permanent neurological deficits and death from respiratory failure. In the patient with acute neurological deficits, immediate correction of coagulation issues is required before decompressive surgery.

Diagnosis of cervical epidural hematoma is complicated by the rarity of the event and the lack of specific symptoms. When trauma is involved, cervical disc or nerve root injury is a more likely cause of sudden onset of neck pain, with rapid development of a radicular component. However, when symptoms occur following minor exertion (eg, sneezing, coitus, coughing) and in the presence of risk factors such as hematologic disorders, pregnancy, rheumatologic disorders, or liver dysfunction, epidural hematoma must be considered.¹⁶ Emergent magnetic resonance imaging (MRI) is the modality of choice for detecting this condition (Figure 2).

Coronary Ischemia Angina pectoris secondary to coronary ischemia is described as retrosternal “heaviness” or pressure, which may spread to either or both arms, the neck, or jaw. Pathology originating in the neck can be experienced as chest pain and may confound the diagnosis. Because cervical nerve roots C4-C8 contribute to the innervation of the anterior chest wall, irritation of any one of these nerves secondary to neck pathology can mimic true angina.17,18 Conversely, the likelihood that the only pain caused by coronary ischemia might be felt in the neck is low, but possible— especially in women.19,20 Coronary ischemia should be considered in patients with cardiac risk factors but no other obvious etiology for neck pain.21

Secondary Infection
Since emergency physicians are accustomed to dealing with infection, it is hard to imagine that we could fail to recognize infection as the etiology in a patient with a chief complaint of neck pain. Diagnosis in such cases is complicated by the anatomical location of deep neck-space infections, which limits the usefulness of standard physical examination. These sites are difficult to palpate and often impossible to visualize because they are covered with noninfected tissue. Unless specifically considered in the differential, more obscure causes of neck pain associated with infection may be missed, including retropharyngeal abscess, epiglottitis, Ludwig’s angina, vertebral osteomyelitis and discitis, cervical epidural abscess, and Lemierre’s syndrome.

Epiglottitis
Epiglottitis is inflammation of the epiglottis and adjacent supraglottic structures including the pharynx, uvula, and base of the tongue. The first recorded case is thought to have been that of George Washington, who is believed to have died from this disease.²² The high mortality rate (7% to 20% in the adult population) is a direct result of airway obstruction from inflammatory edema of the epiglottis and adjacent tissues.

Epiglottitis was originally considered a childhood disease; however, the widespread use of Haemophilus influenza vaccination has resulted in a decline in pediatric incidence. Most cases are now seen in adults (mean age of 46 years).^23,24

Bacterial infection, especially from the genera Hemophilus, Streptococcus, Staphylococcus, and Klebsiella, is by far the most frequent cause of acute epiglottitis; viral and fungal-associated infections are rare. Thermal injury from swallowing hot foods or liquids, and even from inhaling crack cocaine,²⁵ also has been implicated.

Clinical presentations of epiglottitis differ between children and adults. While children are typically dyspneic, drooling, stridorous and febrile, adults tend to present with a milder form of the disease and have painful swallowing, sore throat, and a muffled voice. In both children and adults, the larynx and upper trachea are tender to light palpation at the anterior neck.26 Although sore throat and odynophagia are more often symptoms of pharyngitis, suspicion should be aroused when pain is severe and/or there is dyspnea, severe pain with an unremarkable oropharynx examination, or anterior neck tenderness. When present, muffled voice and stridor indicate greater potential for airway compromise.27 In cases of significant airway obstruction, patients may assume the “tripod position,” leaning forward with neck extended and mouth open—panting. Since soft-tissue lateral neck radiographs are about 90% sensitive and specific for epiglottitis, a normalappearing film cannot reliably exclude the diagnosis.28 Evaluation for the classic “thumb sign” of epiglottic swelling27 (Figure 3) should be combined with the newly described “vallecula sign” for greatest accuracy.29 The vallecula sign is described as the partial or complete obliteration of a well-defined linear air pocket between the base of the tongue and the epiglottis seen on a closed mouth lateral neck X-ray.

Although CT is a useful modality for detecting epiglottic, peritonsillar, or deep neck space abscess, there are risks to patients with airway compromise; moreover, placing patients in a supine position for the study increases the likelihood of respiratory distress. Despite these risks, when indicated, CT is useful in differentiating these abscesses from similarly presenting entities such as lingual tonsillitis and upper airway foreign body.

Direct visualization via flexible oral or nasolaryngoscopy is the diagnostic gold standard but may be deferred in a stable patient. When absolutely indicated, it must be performed with caution, ideally by an anesthesiologist/otolaryngologist in a controlled setting, lest it precipitate further obstruction. Through the use of fiber optics, the need for emergent intubation can be more directly assessed and, if necessary, performed by “tube-over-scope” technique. In the ED, standby equipment for intubation and cricothyrotomy/needle cricothyrotomy should be immediately available and ready in the event of rapid deterioration, at the same time as intravenous (IV) infusion of third-generation cephalosporin or ampicillin/sulbactam, and methicillin-resistant Staphylococcus aureus (MRSA) coverage. Though the rationale for empirical use of antibiotics is evident, the role of corticosteroids and of nebulized racemic epinephrine is controversial.

Death, airway obstruction, epiglottic abscess, necrotizing epiglottitis, and secondary infections (eg, pneumonia, cervical adenitis, septic arthritis, meningitis) are the potential complications that make this source of neck pain one not to be missed. If epiglottitis is suspected, the patient must be admitted to an intensive care setting.

Retropharyngeal Abscess
The retropharyngeal space, immediately behind the posterior pharynx and esophagus, extends from the base of the skull to the mediastinum. It lies anterior to the deep cervical fascia and is bound laterally by the carotid sheaths.30 Because it is fused down the midline, abscesses in this area tend to be unilateral. The space cannot be directly assessed by physical examination, and infections in this area are rare. Timely diagnosis demands consideration of retropharyngeal abscess in patients presenting with fever, neck stiffness, and sore throat. The potential for serious morbidity and mortality is related to the host of vital structures immediately adjacent to the retropharyngeal space. Complications include mediastinitis, carotid artery erosion, jugular vein thrombosis, pericarditis, epidural abscess, sepsis, and airway compromise.

Most cases are typically observed in children younger than age 6 years. In this pediatric population, the retropharyngeal space has two parallel chains of lymph nodes draining the nose, sinuses, and pharynx; retropharyngeal abscesses usually occur as a suppurative extension from infections of these upper airway structures structures. Penetrating trauma, eg, from objects held in the mouth, is another possible cause. These nodes atrophy around 6 years of age; thereafter, the main cause of retropharyngeal abscess is purulent extension of an adjacent (frequently odontogenic) infection or posterior pharyngeal trauma (eg, from a fish bone or instrumentation).³¹ As befits its origin with oral flora, cultures are almost always polymicrobial (eg, Streptococci viridans and pyogenes, Staphylococcus, H influenza, Klebsiella, anaerobes).

Although retropharyngeal abscess is considered a disease of childhood, like epiglottitis, its incidence in adults is increasing. ³² Presenting symptoms are signs of respiratory distress, such as wheezing, stridor, and drooling with impending airway obstruction from the expanding posterior pharyngeal mass. Late signs of the illness are respiratory failure due to airway obstruction and septic shock, but an astute clinician should recognize the entity long before these symptoms present. Early symptoms include fever, sore throat, odynophagia, and neck pain and stiffness (typically manifesting as a reluctance to turn the neck).³³ Patients may also complain of feeling a lump in the throat or pain in the posterior neck or shoulder with swallowing.³⁴ Ninety-seven percent of pediatric patients present with neck pain,³² which could manifest dramatically as torticollis. Most likely, a child will have a subtle reluctance to move his or her neck during the course of the physical examination. In addition, there may be posterior pharyngeal edema and/or a visible unilateral posterior pharyngeal bulge, cervical adenopathy, and a “croupy” cry or cough resembling a duck’s quack—the “cri du canard.”³⁵ Definitive diagnosis is made using X-ray and/or CT. A lateral soft-tissue neck X-ray will demonstrate widening of the prevertebral soft tissues. CT with contrast provides a more definitive diagnosis, and is also useful to differentiate abscess (ie, a hypodense lesion with ring enhancement) from cellulitis.

Regarding treatment, empiric IV antibiotics must be started immediately and may alone prevent progression if the diagnosis is made before cellulitis has progressed to abscess. Intravenous clindamycin is a reasonable first-line antibiotic; other suggested drugs include a penicillin/ beta lactamase inhibitor, penicillin G plus metronidazole, and cefoxitin.36 Airway protection is mandatory, and an otolaryngologist should be consulted early. Because of the potential for sudden airway deterioration, the emergency physician must be prepared to establish a surgical airway.

Ludwig’s Angina
Ludwig’s angina derives its name from the German physician Wilhelm Friedrich von Ludwig, who first described this deadly, rapidly progressive, fascial space/ connective tissue gangrenous cellulitis of the floor of the mouth and adjoining neck in 1836. In a curious twist of fate, it is believed that Dr Ludwig died from this very disease that bears his name.³⁷

Ninety percent of cases of Ludwig’s angina are odontogenic, often due to periapical abscesses. This condition may result secondary to any oral or parapharyngeal infection that spreads by continuity from the submandibular space into the contiguous sublingual and submental spaces. The potential for airway obstruction comes from elevation and displacement of the tongue, resulting in a mortality rate greater than 50% if untreated. Causative organisms mirror normal, polymicrobial oral flora and include Staphylococcus, Streptococcus, Fusobacterium, and Bacteroides.^38,23

Diagnosis of Ludwig’s angina is primarily clinical. Neck pain and swelling, dental pain, dysphagia, malaise, and fever, along with a protruding or elevated tongue, are typical. Submandibular swelling, which is seen in 95% of patients, develops in advanced cases into an intense “woody” induration above the hyoid bone that portends the impending airway crisis.³⁹ If the patient is sufficiently clinically stable and able to lie flat, definitive diagnosis can be made with a contrastenhanced, soft-tissue neck CT (Figure 4), which can also evaluate for a drainable abscess, soft-tissue gas, and mediastinal extension; this modality can also define the extent of soft-tissue swelling and airway patency.

Airway management is the primary consideration because of its potential for rapid deterioration. Traditional management has been aggressive and surgical, with the standard being early tracheostomy. More recent reports have encouraged more conservative management when possible.40 Impending or actual airway compromise, as manifest by significant trismus, inability to flex the neck without compromising the airway, inability to protrude the tongue, or actual resting dyspnea demand that a surgical airway be readied at bedside until fiber optic nasotracheal intubation is secured.

Antibiotics must be given early and include coverage for gram-positive, gramnegative, and anaerobic organisms. Intravenous metronidazole and penicillin (cefazolin or clindamycin if patient has an allergy to penicillin) are commonly prescribed.^38,23 Although controversial, administration of IV dexamethasone (8 mg to 12 mg) and nebulized epinephrine (1:1000, 1 mL diluted to 5 mL with normal saline) to reduce edema has been advocated. ⁴¹

Lemierre’s Syndrome Lemierre’s syndrome, septic thrombophlebitis of the internal jugular vein, was first described in 1936 by André Lemierre, who published a series of cases of previously healthy young adults in whom oropharyngeal infections were followed by “anaerobic postanginal septicaemias.”42 Most of these patients presented with sore throat (referred to as “angina” in “old skool” speak) and worsening pain and tenderness at the anterolateral neck, with pulmonary symptoms manifesting several days to 2 weeks later. The causative organism, Fusobacterium necrophorum, is a gram-negative anaerobe that is part of the normal commensal oropharyngeal flora. It invades the internal jugular (IJ) vein via the lateral pharyngeal space and releases a hemagglutinin that promotes thrombus formation in the IJ and, ultimately, metastatic septic emboli. These emboli typically invade the lungs and cause multiple nodular infiltrates and small pleural effusions. Unfortunately, as each case is unique, diagnosis is often delayed. Septic emboli can migrate to other sites and cause arthritis (hip, knee, shoulder, sacroiliac, and other joints), osteomyelitis, young adult with a history of recent sore throat and fever who subsequently developed neck pain and tenderness (with or without swelling) over the IJ, rigors, pulmonary infiltrates, and possibly other signs of septic emboli.

Doppler ultrasound or CT will show IJ thrombosis43 (Figure 5). Purulent discharge, if obtained, has a characteristic foul smell that has been likened to “limburger or overripe Camembert cheese.”44 Treatment is with high-dose IV penicillin and metronidazole or with clindamycin as single coverage. Heparin could potentially aid in dissemination of emboli, but it is used only when there is retrograde propagation of clot to the cavernous sinus.

With the routine antibiotic treatment of pharyngitis in the 1960s and 1970s, cases of Lemierre’s syndrome became so rare that it was referred to as the “forgotten disease.”⁴⁵ Unfortunately, its incidence has increased over the past few years.⁴³ It is unclear whether this rise is due to increasing antibiotic resistance or to an increasing resistance of clinicians to use antibiotics for “sore throats.”

Cervical Spinal Infections
Vertebral osteomyelitis, discitis, and spinal epidural abscess are rare in developed countries. Most cases stem from hematogenous seeding, skin abscesses, and urinary tract infections but can also originate from a host of other sites, including penetrating trauma and invasive spinal procedures (eg, lumbar punctures, epidural injections). ^46,47 Cervical spine infections are associated with immune-compromising situations or conditions (eg, IV drug use, diabetes mellitus, malignancy, acquired immunodeficiency syndrome, renal insufficiency, long-term use of systemic corticosteroids).

All three of these conditions present similarly, often as localized neck pain that grows more intense over a period of days to weeks and worsens with neck movement. Neurological signs ordinarily appear late in the course of the illness. Fever is a classic symptom but is not always present.⁴⁸ There is usually tenderness over the involved spinous process. The development of motor or sensory loss suggests formation of an abscess,⁴⁹ which can rapidly lead to further compressive symptoms and sepsis.

Leukocytosis may be absent but erythrocyte sedimentation rate and C-reactive protein are often elevated. A CT scan with contrast is frequently required for diagnosis, though when available, MRI with IV gadolinium is the test of choice (Figure 6). Most cases are caused by S aureus, but antibiotic coverage for gram-positive organisms (including MRSA), gram-negative organisms, and anaerobes should be started as soon as blood cultures are drawn. Neurosurgery should be consulted emergently since, with cervical epidural abscess, neurological deterioration—even to the point of total paralysis—can develop in a matter of hours.⁵⁰

Conclusion
Although most patients presenting to the ED with neck pain are musculoskeletal and associated with a traumatic event, other infrequent but potentially serious atraumatic causes may be present. Based on a patient’s symptoms, emergency physicians should also consider these conditions in the differential diagnosis to ensure rapid treatment to prevent further complications.

The English expression, “a pain in the neck” is said to have originated in the early 1900s as a euphemism for the less polite phrase, “a pain in the ass.”¹ While one might wonder how the expressions of such disparate discomforts came to be idiomatically equivalent, the focus of this article is on etiology of the former. All wryness aside, since most ED presentations of neck pain are musculoskeletal in origin, one may easily fail to consider the myriad of less common, but possibly serious, causes.

Pain can originate from any part of the neck and occur as a result of inflammation (eg, infections and arthritides), vascular pathology (eg, cervical artery dissection [CAD]), spaceoccupying lesions (eg, hematomas, cysts, tumors), or even as referred pain from noncervical sources (eg, heart, diaphragm, lung apex). Any lesion encroaching on the limited space of the neck can quickly compromise the airway, compress nerves, or inhibit blood flow to the brain; therefore, knowledge of the causes of such conditions is critical. This article reviews some of the less common and generally atraumatic etiologies of nontraumatic neck pain of which the emergency physician should be familiar.

Vascular Disorders
Vascular-associated neck pain can originate from vessels within the neck or represent referred pain from a more distant structure. In both cases, however, the potential for morbidity is high and the need for consideration and timely recognition crucial.

Cervical Artery Dissection
The typical initial presenting symptom of CAD—ie, internal CAD (ICAD) or vertebral artery dissection (VAD)—is severe pain in the ipsilateral neck and/or head. Onset of pain may be sudden or gradual.² CAD occurs in an estimated 2 or 3 of every 100,000 people per year, mostly in patients between ages 20 and 40 years, and it is considered the most common cause of stroke in patients younger than age 45 years.² The pain associated with CAD generally follows trauma. While the precipitating trauma can be a major blunt or penetrating one, it is often caused by something seemingly trivial, such as “trauma” associated with coughing, painting a ceiling, yoga, or (classically and notoriously) chiropractic manipulation.³ There is frequently some rotational component to CAD-associated trauma,⁴ though dissection may occur spontaneously.⁵

The typical triad of symptoms is ipsilateral neck and/or head pain, partial Horner’s syndrome (ptosis and miosis without anhidrosis), and signs of cerebral ischemia. However, patients do not always present with all three of these symptoms, which can complicate the diagnosis. For example, in some patients, neck pain is the sole presenting symptom and can mimic the musculoskeletal pain expected from the mechanical strain that precipitated the dissection.⁶ In addition, partial Horner’s syndrome occurs in only 50% of cases, and ischemic symptoms might not present for hours to weeks after the onset of neck pain.⁶

In almost all cases of CAD, initial symptoms are otherwise unexplained pain described as a constant, steady aching. ⁷ Since cervical arteries are heavily invested with pain fibers,⁸ an intimal tear with dissecting intramural hematoma provokes pain. Pain associated with VAD is usually severe, unilateral, posterior neck, and/or occipital, while ICAD-associated pain is ipsilateral, anterolateral neck, head, and/or face. It is important to note that head or neck pain caused by a dissection normally precedes the ischemic manifestation as opposed to the more common stroke, in which the ischemia precedes or is simultaneous with the accompanying headache.⁹

Ischemic neurological symptoms can arise from stenosis of the arterial lumen, secondary to an expanding intramural hematoma; a luminal thrombus developing at the intimal defect; or an embolization accompanied by ipsilateral Horner’s syndrome, any cranial nerve abnormality, or followed by cerebral or ocular ischemic symptoms (even if transient). A diagnosis is usually made through vascular ultrasound (Figure 1) and confirmed with computed tomography angiography (CTA) or magnetic resonance angiography. When requesting a CTA of the neck, the emergency physician should specifically make note of suspected CAD in the order. Immediate treatment includes a cervical collar and neurosurgical consultation even though treatment is essentially medical and surgery is rarely required. Anticoagulation therapy is routinely initiated to prevent thrombus propagation or embolization (unless there is brain hemorrhage). Antiplatelet therapy may be equally efficacious, ¹⁰ and can be initiated upon suspicions of CAD and while confirmatory studies are in progress. The prognosis for extracranial dissections is generally good.

Cervical Epidural Hematoma Cervical (spinal) epidural hematoma is an uncommon but potentially catastrophic event that can lead to permanent neurological deficits and death from respiratory failure. It presents as sudden and severe local neck pain with rapid development of radicular pain at the corresponding dermatomes. Motor and sensory deficits follow within minutes to days.12,13 Bleeding can occur spontaneously or secondary to trauma, surgery, or coagulopathy (which itself may be pathological—eg, hemophilia or iatrogenic in origin).14,15 Untreated, progressive cord compression can lead to permanent neurological deficits and death from respiratory failure. In the patient with acute neurological deficits, immediate correction of coagulation issues is required before decompressive surgery.

Diagnosis of cervical epidural hematoma is complicated by the rarity of the event and the lack of specific symptoms. When trauma is involved, cervical disc or nerve root injury is a more likely cause of sudden onset of neck pain, with rapid development of a radicular component. However, when symptoms occur following minor exertion (eg, sneezing, coitus, coughing) and in the presence of risk factors such as hematologic disorders, pregnancy, rheumatologic disorders, or liver dysfunction, epidural hematoma must be considered.¹⁶ Emergent magnetic resonance imaging (MRI) is the modality of choice for detecting this condition (Figure 2).

Coronary Ischemia Angina pectoris secondary to coronary ischemia is described as retrosternal “heaviness” or pressure, which may spread to either or both arms, the neck, or jaw. Pathology originating in the neck can be experienced as chest pain and may confound the diagnosis. Because cervical nerve roots C4-C8 contribute to the innervation of the anterior chest wall, irritation of any one of these nerves secondary to neck pathology can mimic true angina.17,18 Conversely, the likelihood that the only pain caused by coronary ischemia might be felt in the neck is low, but possible— especially in women.19,20 Coronary ischemia should be considered in patients with cardiac risk factors but no other obvious etiology for neck pain.21

Secondary Infection
Since emergency physicians are accustomed to dealing with infection, it is hard to imagine that we could fail to recognize infection as the etiology in a patient with a chief complaint of neck pain. Diagnosis in such cases is complicated by the anatomical location of deep neck-space infections, which limits the usefulness of standard physical examination. These sites are difficult to palpate and often impossible to visualize because they are covered with noninfected tissue. Unless specifically considered in the differential, more obscure causes of neck pain associated with infection may be missed, including retropharyngeal abscess, epiglottitis, Ludwig’s angina, vertebral osteomyelitis and discitis, cervical epidural abscess, and Lemierre’s syndrome.

Epiglottitis
Epiglottitis is inflammation of the epiglottis and adjacent supraglottic structures including the pharynx, uvula, and base of the tongue. The first recorded case is thought to have been that of George Washington, who is believed to have died from this disease.²² The high mortality rate (7% to 20% in the adult population) is a direct result of airway obstruction from inflammatory edema of the epiglottis and adjacent tissues.

Epiglottitis was originally considered a childhood disease; however, the widespread use of Haemophilus influenza vaccination has resulted in a decline in pediatric incidence. Most cases are now seen in adults (mean age of 46 years).^23,24

Bacterial infection, especially from the genera Hemophilus, Streptococcus, Staphylococcus, and Klebsiella, is by far the most frequent cause of acute epiglottitis; viral and fungal-associated infections are rare. Thermal injury from swallowing hot foods or liquids, and even from inhaling crack cocaine,²⁵ also has been implicated.

Clinical presentations of epiglottitis differ between children and adults. While children are typically dyspneic, drooling, stridorous and febrile, adults tend to present with a milder form of the disease and have painful swallowing, sore throat, and a muffled voice. In both children and adults, the larynx and upper trachea are tender to light palpation at the anterior neck.26 Although sore throat and odynophagia are more often symptoms of pharyngitis, suspicion should be aroused when pain is severe and/or there is dyspnea, severe pain with an unremarkable oropharynx examination, or anterior neck tenderness. When present, muffled voice and stridor indicate greater potential for airway compromise.27 In cases of significant airway obstruction, patients may assume the “tripod position,” leaning forward with neck extended and mouth open—panting. Since soft-tissue lateral neck radiographs are about 90% sensitive and specific for epiglottitis, a normalappearing film cannot reliably exclude the diagnosis.28 Evaluation for the classic “thumb sign” of epiglottic swelling27 (Figure 3) should be combined with the newly described “vallecula sign” for greatest accuracy.29 The vallecula sign is described as the partial or complete obliteration of a well-defined linear air pocket between the base of the tongue and the epiglottis seen on a closed mouth lateral neck X-ray.

Although CT is a useful modality for detecting epiglottic, peritonsillar, or deep neck space abscess, there are risks to patients with airway compromise; moreover, placing patients in a supine position for the study increases the likelihood of respiratory distress. Despite these risks, when indicated, CT is useful in differentiating these abscesses from similarly presenting entities such as lingual tonsillitis and upper airway foreign body.

Direct visualization via flexible oral or nasolaryngoscopy is the diagnostic gold standard but may be deferred in a stable patient. When absolutely indicated, it must be performed with caution, ideally by an anesthesiologist/otolaryngologist in a controlled setting, lest it precipitate further obstruction. Through the use of fiber optics, the need for emergent intubation can be more directly assessed and, if necessary, performed by “tube-over-scope” technique. In the ED, standby equipment for intubation and cricothyrotomy/needle cricothyrotomy should be immediately available and ready in the event of rapid deterioration, at the same time as intravenous (IV) infusion of third-generation cephalosporin or ampicillin/sulbactam, and methicillin-resistant Staphylococcus aureus (MRSA) coverage. Though the rationale for empirical use of antibiotics is evident, the role of corticosteroids and of nebulized racemic epinephrine is controversial.

Death, airway obstruction, epiglottic abscess, necrotizing epiglottitis, and secondary infections (eg, pneumonia, cervical adenitis, septic arthritis, meningitis) are the potential complications that make this source of neck pain one not to be missed. If epiglottitis is suspected, the patient must be admitted to an intensive care setting.

Retropharyngeal Abscess
The retropharyngeal space, immediately behind the posterior pharynx and esophagus, extends from the base of the skull to the mediastinum. It lies anterior to the deep cervical fascia and is bound laterally by the carotid sheaths.30 Because it is fused down the midline, abscesses in this area tend to be unilateral. The space cannot be directly assessed by physical examination, and infections in this area are rare. Timely diagnosis demands consideration of retropharyngeal abscess in patients presenting with fever, neck stiffness, and sore throat. The potential for serious morbidity and mortality is related to the host of vital structures immediately adjacent to the retropharyngeal space. Complications include mediastinitis, carotid artery erosion, jugular vein thrombosis, pericarditis, epidural abscess, sepsis, and airway compromise.

Most cases are typically observed in children younger than age 6 years. In this pediatric population, the retropharyngeal space has two parallel chains of lymph nodes draining the nose, sinuses, and pharynx; retropharyngeal abscesses usually occur as a suppurative extension from infections of these upper airway structures structures. Penetrating trauma, eg, from objects held in the mouth, is another possible cause. These nodes atrophy around 6 years of age; thereafter, the main cause of retropharyngeal abscess is purulent extension of an adjacent (frequently odontogenic) infection or posterior pharyngeal trauma (eg, from a fish bone or instrumentation).³¹ As befits its origin with oral flora, cultures are almost always polymicrobial (eg, Streptococci viridans and pyogenes, Staphylococcus, H influenza, Klebsiella, anaerobes).

Although retropharyngeal abscess is considered a disease of childhood, like epiglottitis, its incidence in adults is increasing. ³² Presenting symptoms are signs of respiratory distress, such as wheezing, stridor, and drooling with impending airway obstruction from the expanding posterior pharyngeal mass. Late signs of the illness are respiratory failure due to airway obstruction and septic shock, but an astute clinician should recognize the entity long before these symptoms present. Early symptoms include fever, sore throat, odynophagia, and neck pain and stiffness (typically manifesting as a reluctance to turn the neck).³³ Patients may also complain of feeling a lump in the throat or pain in the posterior neck or shoulder with swallowing.³⁴ Ninety-seven percent of pediatric patients present with neck pain,³² which could manifest dramatically as torticollis. Most likely, a child will have a subtle reluctance to move his or her neck during the course of the physical examination. In addition, there may be posterior pharyngeal edema and/or a visible unilateral posterior pharyngeal bulge, cervical adenopathy, and a “croupy” cry or cough resembling a duck’s quack—the “cri du canard.”³⁵ Definitive diagnosis is made using X-ray and/or CT. A lateral soft-tissue neck X-ray will demonstrate widening of the prevertebral soft tissues. CT with contrast provides a more definitive diagnosis, and is also useful to differentiate abscess (ie, a hypodense lesion with ring enhancement) from cellulitis.

Regarding treatment, empiric IV antibiotics must be started immediately and may alone prevent progression if the diagnosis is made before cellulitis has progressed to abscess. Intravenous clindamycin is a reasonable first-line antibiotic; other suggested drugs include a penicillin/ beta lactamase inhibitor, penicillin G plus metronidazole, and cefoxitin.36 Airway protection is mandatory, and an otolaryngologist should be consulted early. Because of the potential for sudden airway deterioration, the emergency physician must be prepared to establish a surgical airway.

Ludwig’s Angina
Ludwig’s angina derives its name from the German physician Wilhelm Friedrich von Ludwig, who first described this deadly, rapidly progressive, fascial space/ connective tissue gangrenous cellulitis of the floor of the mouth and adjoining neck in 1836. In a curious twist of fate, it is believed that Dr Ludwig died from this very disease that bears his name.³⁷

Ninety percent of cases of Ludwig’s angina are odontogenic, often due to periapical abscesses. This condition may result secondary to any oral or parapharyngeal infection that spreads by continuity from the submandibular space into the contiguous sublingual and submental spaces. The potential for airway obstruction comes from elevation and displacement of the tongue, resulting in a mortality rate greater than 50% if untreated. Causative organisms mirror normal, polymicrobial oral flora and include Staphylococcus, Streptococcus, Fusobacterium, and Bacteroides.^38,23

Diagnosis of Ludwig’s angina is primarily clinical. Neck pain and swelling, dental pain, dysphagia, malaise, and fever, along with a protruding or elevated tongue, are typical. Submandibular swelling, which is seen in 95% of patients, develops in advanced cases into an intense “woody” induration above the hyoid bone that portends the impending airway crisis.³⁹ If the patient is sufficiently clinically stable and able to lie flat, definitive diagnosis can be made with a contrastenhanced, soft-tissue neck CT (Figure 4), which can also evaluate for a drainable abscess, soft-tissue gas, and mediastinal extension; this modality can also define the extent of soft-tissue swelling and airway patency.

Airway management is the primary consideration because of its potential for rapid deterioration. Traditional management has been aggressive and surgical, with the standard being early tracheostomy. More recent reports have encouraged more conservative management when possible.40 Impending or actual airway compromise, as manifest by significant trismus, inability to flex the neck without compromising the airway, inability to protrude the tongue, or actual resting dyspnea demand that a surgical airway be readied at bedside until fiber optic nasotracheal intubation is secured.

Antibiotics must be given early and include coverage for gram-positive, gramnegative, and anaerobic organisms. Intravenous metronidazole and penicillin (cefazolin or clindamycin if patient has an allergy to penicillin) are commonly prescribed.^38,23 Although controversial, administration of IV dexamethasone (8 mg to 12 mg) and nebulized epinephrine (1:1000, 1 mL diluted to 5 mL with normal saline) to reduce edema has been advocated. ⁴¹

Lemierre’s Syndrome Lemierre’s syndrome, septic thrombophlebitis of the internal jugular vein, was first described in 1936 by André Lemierre, who published a series of cases of previously healthy young adults in whom oropharyngeal infections were followed by “anaerobic postanginal septicaemias.”42 Most of these patients presented with sore throat (referred to as “angina” in “old skool” speak) and worsening pain and tenderness at the anterolateral neck, with pulmonary symptoms manifesting several days to 2 weeks later. The causative organism, Fusobacterium necrophorum, is a gram-negative anaerobe that is part of the normal commensal oropharyngeal flora. It invades the internal jugular (IJ) vein via the lateral pharyngeal space and releases a hemagglutinin that promotes thrombus formation in the IJ and, ultimately, metastatic septic emboli. These emboli typically invade the lungs and cause multiple nodular infiltrates and small pleural effusions. Unfortunately, as each case is unique, diagnosis is often delayed. Septic emboli can migrate to other sites and cause arthritis (hip, knee, shoulder, sacroiliac, and other joints), osteomyelitis, young adult with a history of recent sore throat and fever who subsequently developed neck pain and tenderness (with or without swelling) over the IJ, rigors, pulmonary infiltrates, and possibly other signs of septic emboli.

Doppler ultrasound or CT will show IJ thrombosis43 (Figure 5). Purulent discharge, if obtained, has a characteristic foul smell that has been likened to “limburger or overripe Camembert cheese.”44 Treatment is with high-dose IV penicillin and metronidazole or with clindamycin as single coverage. Heparin could potentially aid in dissemination of emboli, but it is used only when there is retrograde propagation of clot to the cavernous sinus.

With the routine antibiotic treatment of pharyngitis in the 1960s and 1970s, cases of Lemierre’s syndrome became so rare that it was referred to as the “forgotten disease.”⁴⁵ Unfortunately, its incidence has increased over the past few years.⁴³ It is unclear whether this rise is due to increasing antibiotic resistance or to an increasing resistance of clinicians to use antibiotics for “sore throats.”

Cervical Spinal Infections
Vertebral osteomyelitis, discitis, and spinal epidural abscess are rare in developed countries. Most cases stem from hematogenous seeding, skin abscesses, and urinary tract infections but can also originate from a host of other sites, including penetrating trauma and invasive spinal procedures (eg, lumbar punctures, epidural injections). ^46,47 Cervical spine infections are associated with immune-compromising situations or conditions (eg, IV drug use, diabetes mellitus, malignancy, acquired immunodeficiency syndrome, renal insufficiency, long-term use of systemic corticosteroids).

All three of these conditions present similarly, often as localized neck pain that grows more intense over a period of days to weeks and worsens with neck movement. Neurological signs ordinarily appear late in the course of the illness. Fever is a classic symptom but is not always present.⁴⁸ There is usually tenderness over the involved spinous process. The development of motor or sensory loss suggests formation of an abscess,⁴⁹ which can rapidly lead to further compressive symptoms and sepsis.

Leukocytosis may be absent but erythrocyte sedimentation rate and C-reactive protein are often elevated. A CT scan with contrast is frequently required for diagnosis, though when available, MRI with IV gadolinium is the test of choice (Figure 6). Most cases are caused by S aureus, but antibiotic coverage for gram-positive organisms (including MRSA), gram-negative organisms, and anaerobes should be started as soon as blood cultures are drawn. Neurosurgery should be consulted emergently since, with cervical epidural abscess, neurological deterioration—even to the point of total paralysis—can develop in a matter of hours.⁵⁰

Conclusion
Although most patients presenting to the ED with neck pain are musculoskeletal and associated with a traumatic event, other infrequent but potentially serious atraumatic causes may be present. Based on a patient’s symptoms, emergency physicians should also consider these conditions in the differential diagnosis to ensure rapid treatment to prevent further complications.