A Roundup Of Highlights From The Meeting

Diffusion Tensor Imaging Suggests Brain Compensation After Traumatic Injury
A special MRI technique may be able to predict which patients who have experienced concussions will improve, according to researchers. The results suggest that in some patients, the brain may change to compensate for the damage caused by the injury.

“This finding could lead to strategies for preventing and repairing the damage that accompanies traumatic brain injury [TBI],” said Michael Lipton, MD, PhD, Associate Director of the Gruss Magnetic Resonance Research Center at Albert Einstein College of Medicine of Yeshiva University and Medical Director of MRI Services at Montefiore Medical Center, both in Bronx, New York.

Each year, 1.7 million people in the United States sustain a TBI, according to the CDC. Concussions and other mild TBIs (or mTBIs) account for at least 75% of these injuries. Following a concussion, some patients experience a brief loss of consciousness. Other symptoms include headache, dizziness, memory loss, attention deficit, depression, and anxiety. Some of these conditions may persist for months or years in as many as 30% of patients.

The study involved 17 patients who were admitted to the emergency department at Montefiore and Jacobi Medical Centers and diagnosed with mTBI. Within two weeks of their injuries, the patients underwent diffusion tensor imaging (DTI), which reveals the movement of water molecules within and along axons. DTI allows researchers to measure the uniformity of water movement (fractional anisotropy) throughout the brain. Areas of low fractional anisotropy indicate axonal injury, and areas of abnormally high fractional anisotropy indicate changes in the brain.

“In a TBI, it’s not one specific area that is affected, but multiple areas of the brain that are interconnected by axons,” said Dr. Lipton. “Abnormally low fractional anisotropy within white matter has been correlated with cognitive impairment in concussion patients. We believe that high fractional anisotropy is evidence not of axonal injury, but of brain changes that are occurring in response to the trauma.”

One year after their brain injury, the patients completed two standard questionnaires to assess their postconcussion symptoms and evaluate their health status and quality of life. “Most TBI studies assess cognitive function, but it is not at all clear if and how well such measures assess real-life functioning,” said Dr. Lipton. “Our questionnaires asked about postconcussion symptoms and how those symptoms affected patients’ health and quality of life.”

After comparing the DTI data to the patient questionnaires, the researchers found that abnormally high fractional anisotropy predicted fewer postconcussion symptoms and better functioning. The results suggest that the brain may be actively compensating for its injuries in patients who exhibit areas of high fractional anisotropy on DTI.

“These results could lead to better treatment for concussion if we can find ways to enhance the brain’s compensatory mechanisms,” Dr. Lipton said.

Exercise Rate Related to Improvements in Parkinson’s Disease
People with Parkinson’s disease may benefit from exercise programs on stationary bicycles, and patients who pedal fastest may obtain the greatest benefit. Functional connectivity MRI (fcMRI) data showed that faster pedaling led to greater connectivity in brain areas associated with motor ability.

After Jay L. Alberts, PhD, a neuroscientist at the Cleveland Clinic Lerner Research Institute, rode a tandem bicycle across Iowa with a patient with Parkinson’s disease, the patient experienced improvements in her symptoms.

“The finding was serendipitous,” said Dr. Alberts. “I was pedaling faster than she was, which forced her to pedal faster. She had improvements in her upper extremity function, so we started to look at the possible mechanism behind this improved function.”

As part of this inquiry, Dr. Alberts, researcher Chintan Shah, BS, and their Cleveland Clinic colleagues used fcMRI to study the effect of exercise on 26 patients with Parkinson’s disease.

“By measuring changes in blood oxygenation levels in the brain, fcMRI allows us to look at the functional connectivity between different brain regions,” said Mr. Shah.

The patients underwent bicycle exercise sessions three times per week for eight weeks. Some patients exercised at a voluntary level, and others underwent forced-rate exercise, pedaling at a speed above their voluntary rate. The researchers induced forced-rate activity with a modified exercise bike.

“We developed an algorithm to control a motor on the bike and used a controller to sense the patient’s rate of exertion and adjust the motor based on his or her input,” said Dr. Alberts.

The researchers conducted fcMRI before and after the eight weeks of exercise therapy and again as follow-up four weeks later. The team calculated brain activation and connectivity levels from the fcMRI results and correlated the data with average pedaling rate. Results showed increases in task-related connectivity between the primary motor cortex and the posterior region of the thalamus. Faster pedaling rate was the key factor related to these improvements, which were still evident at follow-up.

“The results show that forced-rate bicycle exercise is an effective, low-cost therapy for Parkinson’s disease,” Mr. Shah said.

Dr. Alberts noted that that while faster pedaling led to more significant results, not all patients with Parkinson’s disease need to do forced-rate exercise to see improvement. “We’re now looking at this phenomenon in patients with exercise bikes in their home, and other exercises like swimming and rowing on tandem machines may provide similar benefits,” he said.

Gender-Based Differences Observed in Alzheimer’s Disease
All patients with Alzheimer’s disease lose brain cells, which leads to atrophy of the brain. However, the pattern of gray matter loss is significantly different between men and women, according to investigators.

“We found that the extent and distribution of regional gray matter volume loss in the brain was strongly influenced by gender,” said lead researcher Maria Vittoria Spampinato, MD, Associate Professor of Radiology at the Medical University of South Carolina in Charleston.

“There is a strong interest in using MRI to assess brain atrophy with the purpose of monitoring dementia progression noninvasively and to aid in understanding which factors can influence brain atrophy progression and distribution in the Alzheimer’s brain,” said Dr. Spampinato.

Dr. Spampinato and colleagues analyzed data on 109 patients, including 60 men and 49 women (mean age, 77), who participated in the Alzheimer’s Disease Neuroimaging Initiative, a major study that followed hundreds of cognitively healthy individuals and patients with mild cognitive impairment (MCI) and Alzheimer’s disease for five years.

During the five-year period, each of the 109 patients progressed from amnestic MCI to Alzheimer’s disease. Using MRI scans of the patients’ brains taken when they were diagnosed with Alzheimer’s disease and 12 months before and after the diagnosis, the researchers created brain maps that illustrated gray matter changes.

The brain maps revealed that, compared with male patients, women had greater atrophy in gray matter 12 months before their Alzheimer’s disease diagnosis and at the time of their diagnosis. The brain maps also showed that men and women in the study lost gray matter volume in different areas of the brain as their disease progressed from MCI to Alzheimer’s disease.

“The female patients in our study initially had more gray matter atrophy than the male patients, but over time, the men caught up,” said Dr. Spampinato. “In the men, the disease developed more aggressively in a shorter period of time.”

The gender differences in atrophy patterns may have important implications for the development of therapies for MCI and Alzheimer’s disease. “These differences should be taken into consideration when testing new drugs in clinical trials,” said Dr. Spampinato. “Knowing the difference between the male and female patterns of atrophy will help researchers better decipher a patient’s response to drug therapy.”

Active Lifestyle May Boost Brain Structure and Slow Alzheimer’s Disease
An active lifestyle may help preserve gray matter in the brains of older adults and could reduce the burden of dementia and Alzheimer’s disease.

To study how an active lifestyle can influence brain structure, Cyrus Raji, MD, PhD, radiology resident at the University of California in Los Angeles, and colleagues examined 876 adults (average age, 78), drawn from the multisite Cardiovascular Health Study. The patients’ condition ranged from normal cognition to Alzheimer’s dementia.

“We had 20 years of clinical data on this group, including BMI and lifestyle habits,” said Dr. Raji. “We drew our patients from four sites across the country, and we were able to assess energy output in the form of kilocalories per week.” The lifestyle factors examined included recreational sports, gardening and yard work, bicycling, dancing, and riding an exercise bicycle.

The researchers used MRI and voxel-based morphometry to model the relationships between energy output and gray matter volume. “Voxel-based morphometry is an advanced method that allows a computer to analyze an MR image and build a mathematical model that helps us to understand the relationship between active lifestyle and gray matter volume,” said Dr. Raji. “Gray matter volume is a key marker of brain health. Larger gray matter volume means a healthier brain. Shrinking volume is seen in Alzheimer’s disease.”

After controlling for age, head size, cognitive impairment, gender, BMI, education, study site location, and white matter disease, the researchers found a strong association between energy output and gray matter volumes in areas of the brain crucial for cognitive function. Greater caloric expenditure was related to larger gray matter volumes in the frontal, temporal, and parietal lobes, including the hippocampus, posterior cingulate, and basal ganglia. There was a strong association between high-energy output and greater gray matter volume in patients with mild cognitive impairment and Alzheimer’s disease.

“Gray matter includes neurons that function in cognition and higher-order cognitive processes,” said Dr. Raji. “The areas of the brain that benefited from an active lifestyle are the ones that consume the most energy and are very sensitive to damage.”

A key aspect of the study was its focus on having variety in lifestyle choices, Dr. Raji noted. “What struck me most about the study results is that it is not one, but a combination of lifestyle choices and activities that benefit the brain,” he said.

The positive influence of an active lifestyle on the brain likely resulted from improved vascular health. “Virtually all of the physical activities examined in this study are some variation of aerobic physical activity, which we know from other work can improve cerebral blood flow and strengthen neuronal connections,” he said. “Additional work needs to be done. However, our initial results show that brain aging can be alleviated through an active lifestyle.”

Researchers Find Physiologic Evidence of Chemo Brain
Chemotherapy may induce changes in the brain that may affect concentration and memory. Using PET and CT, researchers detected physiologic evidence of chemo brain, a common side effect in patients undergoing chemotherapy for cancer treatment.

“The chemo brain phenomenon is described as ‘mental fog’ and ‘loss of coping skills’ by patients who receive chemotherapy,” said Rachel A. Lagos, DO, diagnostic radiology resident at the West Virginia University School of Medicine and West Virginia University Hospitals in Morgantown. “Because this is such a common patient complaint, health care providers have generically referred to its occurrence as ‘chemo brain’ for more than two decades.”

Although the complaint may be common, the cause of chemo brain has been difficult to pinpoint. Previous MRI studies have found small changes in brain volume after chemotherapy, but no definitive link has been found.

Instead of studying chemotherapy’s effect on the brain’s appearance, Dr. Lagos and colleagues set out to identify its effect on brain function. By using PET and CT, they were able to assess changes to the brain’s metabolism after chemotherapy.

“When we looked at the results, we were surprised at how obvious the changes were,” Dr. Lagos said. “Chemo brain phenomenon is more than a feeling. It is not depression. It is a change in brain function observable on PET and CT brain imaging.”

Dr. Lagos and colleagues analyzed PET and CT brain imaging results from 128 patients who had undergone chemotherapy for breast cancer. They used special software to help discern differences in brain metabolism before and after chemotherapy. Results were correlated with patient history, neurologic examinations, and chemotherapy regimens.

PET and CT results demonstrated statistically significant decreases in regional brain metabolism that were closely associated with symptoms of chemo brain phenomenon. “The study shows that there are specific areas of the brain that use less energy following chemotherapy,” said Dr. Lagos. “These brain areas are the ones known to be responsible for planning and prioritizing.” PET and CT could possibly be used to facilitate clinical diagnosis and allow for earlier intervention.

Research has already shown that patients with chemo brain can benefit from the assistance of nutritionists, exercise therapists, massage therapists, and counselors. In one study, cancer patients receiving chemotherapy complained of losing their ability to prepare family meals. “When the researchers provided these patients with written and planned menus for each meal, the women were able to buy the groceries, prepare the meals, and enjoy them with their families,” said Dr. Lagos.

Future studies could lead the way to better treatment for patients experiencing this condition. “The next step is to establish a prospective study that begins assessing new patients at the time of cancer diagnosis,” said Dr. Lagos. “The prospective study has the potential to establish an understanding of the change in brain neurotransmitters during chemotherapy, which may lead to improved treatment or prevention.”

Diffusion Tensor Imaging Suggests Brain Compensation After Traumatic Injury
A special MRI technique may be able to predict which patients who have experienced concussions will improve, according to researchers. The results suggest that in some patients, the brain may change to compensate for the damage caused by the injury.

“This finding could lead to strategies for preventing and repairing the damage that accompanies traumatic brain injury [TBI],” said Michael Lipton, MD, PhD, Associate Director of the Gruss Magnetic Resonance Research Center at Albert Einstein College of Medicine of Yeshiva University and Medical Director of MRI Services at Montefiore Medical Center, both in Bronx, New York.

Each year, 1.7 million people in the United States sustain a TBI, according to the CDC. Concussions and other mild TBIs (or mTBIs) account for at least 75% of these injuries. Following a concussion, some patients experience a brief loss of consciousness. Other symptoms include headache, dizziness, memory loss, attention deficit, depression, and anxiety. Some of these conditions may persist for months or years in as many as 30% of patients.

The study involved 17 patients who were admitted to the emergency department at Montefiore and Jacobi Medical Centers and diagnosed with mTBI. Within two weeks of their injuries, the patients underwent diffusion tensor imaging (DTI), which reveals the movement of water molecules within and along axons. DTI allows researchers to measure the uniformity of water movement (fractional anisotropy) throughout the brain. Areas of low fractional anisotropy indicate axonal injury, and areas of abnormally high fractional anisotropy indicate changes in the brain.

“In a TBI, it’s not one specific area that is affected, but multiple areas of the brain that are interconnected by axons,” said Dr. Lipton. “Abnormally low fractional anisotropy within white matter has been correlated with cognitive impairment in concussion patients. We believe that high fractional anisotropy is evidence not of axonal injury, but of brain changes that are occurring in response to the trauma.”

One year after their brain injury, the patients completed two standard questionnaires to assess their postconcussion symptoms and evaluate their health status and quality of life. “Most TBI studies assess cognitive function, but it is not at all clear if and how well such measures assess real-life functioning,” said Dr. Lipton. “Our questionnaires asked about postconcussion symptoms and how those symptoms affected patients’ health and quality of life.”

After comparing the DTI data to the patient questionnaires, the researchers found that abnormally high fractional anisotropy predicted fewer postconcussion symptoms and better functioning. The results suggest that the brain may be actively compensating for its injuries in patients who exhibit areas of high fractional anisotropy on DTI.

“These results could lead to better treatment for concussion if we can find ways to enhance the brain’s compensatory mechanisms,” Dr. Lipton said.

Exercise Rate Related to Improvements in Parkinson’s Disease
People with Parkinson’s disease may benefit from exercise programs on stationary bicycles, and patients who pedal fastest may obtain the greatest benefit. Functional connectivity MRI (fcMRI) data showed that faster pedaling led to greater connectivity in brain areas associated with motor ability.

After Jay L. Alberts, PhD, a neuroscientist at the Cleveland Clinic Lerner Research Institute, rode a tandem bicycle across Iowa with a patient with Parkinson’s disease, the patient experienced improvements in her symptoms.

“The finding was serendipitous,” said Dr. Alberts. “I was pedaling faster than she was, which forced her to pedal faster. She had improvements in her upper extremity function, so we started to look at the possible mechanism behind this improved function.”

As part of this inquiry, Dr. Alberts, researcher Chintan Shah, BS, and their Cleveland Clinic colleagues used fcMRI to study the effect of exercise on 26 patients with Parkinson’s disease.

“By measuring changes in blood oxygenation levels in the brain, fcMRI allows us to look at the functional connectivity between different brain regions,” said Mr. Shah.

The patients underwent bicycle exercise sessions three times per week for eight weeks. Some patients exercised at a voluntary level, and others underwent forced-rate exercise, pedaling at a speed above their voluntary rate. The researchers induced forced-rate activity with a modified exercise bike.

“We developed an algorithm to control a motor on the bike and used a controller to sense the patient’s rate of exertion and adjust the motor based on his or her input,” said Dr. Alberts.

The researchers conducted fcMRI before and after the eight weeks of exercise therapy and again as follow-up four weeks later. The team calculated brain activation and connectivity levels from the fcMRI results and correlated the data with average pedaling rate. Results showed increases in task-related connectivity between the primary motor cortex and the posterior region of the thalamus. Faster pedaling rate was the key factor related to these improvements, which were still evident at follow-up.

“The results show that forced-rate bicycle exercise is an effective, low-cost therapy for Parkinson’s disease,” Mr. Shah said.

Dr. Alberts noted that that while faster pedaling led to more significant results, not all patients with Parkinson’s disease need to do forced-rate exercise to see improvement. “We’re now looking at this phenomenon in patients with exercise bikes in their home, and other exercises like swimming and rowing on tandem machines may provide similar benefits,” he said.

Gender-Based Differences Observed in Alzheimer’s Disease
All patients with Alzheimer’s disease lose brain cells, which leads to atrophy of the brain. However, the pattern of gray matter loss is significantly different between men and women, according to investigators.

“We found that the extent and distribution of regional gray matter volume loss in the brain was strongly influenced by gender,” said lead researcher Maria Vittoria Spampinato, MD, Associate Professor of Radiology at the Medical University of South Carolina in Charleston.

“There is a strong interest in using MRI to assess brain atrophy with the purpose of monitoring dementia progression noninvasively and to aid in understanding which factors can influence brain atrophy progression and distribution in the Alzheimer’s brain,” said Dr. Spampinato.

Dr. Spampinato and colleagues analyzed data on 109 patients, including 60 men and 49 women (mean age, 77), who participated in the Alzheimer’s Disease Neuroimaging Initiative, a major study that followed hundreds of cognitively healthy individuals and patients with mild cognitive impairment (MCI) and Alzheimer’s disease for five years.

During the five-year period, each of the 109 patients progressed from amnestic MCI to Alzheimer’s disease. Using MRI scans of the patients’ brains taken when they were diagnosed with Alzheimer’s disease and 12 months before and after the diagnosis, the researchers created brain maps that illustrated gray matter changes.

The brain maps revealed that, compared with male patients, women had greater atrophy in gray matter 12 months before their Alzheimer’s disease diagnosis and at the time of their diagnosis. The brain maps also showed that men and women in the study lost gray matter volume in different areas of the brain as their disease progressed from MCI to Alzheimer’s disease.

“The female patients in our study initially had more gray matter atrophy than the male patients, but over time, the men caught up,” said Dr. Spampinato. “In the men, the disease developed more aggressively in a shorter period of time.”

The gender differences in atrophy patterns may have important implications for the development of therapies for MCI and Alzheimer’s disease. “These differences should be taken into consideration when testing new drugs in clinical trials,” said Dr. Spampinato. “Knowing the difference between the male and female patterns of atrophy will help researchers better decipher a patient’s response to drug therapy.”

Active Lifestyle May Boost Brain Structure and Slow Alzheimer’s Disease
An active lifestyle may help preserve gray matter in the brains of older adults and could reduce the burden of dementia and Alzheimer’s disease.

To study how an active lifestyle can influence brain structure, Cyrus Raji, MD, PhD, radiology resident at the University of California in Los Angeles, and colleagues examined 876 adults (average age, 78), drawn from the multisite Cardiovascular Health Study. The patients’ condition ranged from normal cognition to Alzheimer’s dementia.

“We had 20 years of clinical data on this group, including BMI and lifestyle habits,” said Dr. Raji. “We drew our patients from four sites across the country, and we were able to assess energy output in the form of kilocalories per week.” The lifestyle factors examined included recreational sports, gardening and yard work, bicycling, dancing, and riding an exercise bicycle.

The researchers used MRI and voxel-based morphometry to model the relationships between energy output and gray matter volume. “Voxel-based morphometry is an advanced method that allows a computer to analyze an MR image and build a mathematical model that helps us to understand the relationship between active lifestyle and gray matter volume,” said Dr. Raji. “Gray matter volume is a key marker of brain health. Larger gray matter volume means a healthier brain. Shrinking volume is seen in Alzheimer’s disease.”

After controlling for age, head size, cognitive impairment, gender, BMI, education, study site location, and white matter disease, the researchers found a strong association between energy output and gray matter volumes in areas of the brain crucial for cognitive function. Greater caloric expenditure was related to larger gray matter volumes in the frontal, temporal, and parietal lobes, including the hippocampus, posterior cingulate, and basal ganglia. There was a strong association between high-energy output and greater gray matter volume in patients with mild cognitive impairment and Alzheimer’s disease.

“Gray matter includes neurons that function in cognition and higher-order cognitive processes,” said Dr. Raji. “The areas of the brain that benefited from an active lifestyle are the ones that consume the most energy and are very sensitive to damage.”

A key aspect of the study was its focus on having variety in lifestyle choices, Dr. Raji noted. “What struck me most about the study results is that it is not one, but a combination of lifestyle choices and activities that benefit the brain,” he said.

The positive influence of an active lifestyle on the brain likely resulted from improved vascular health. “Virtually all of the physical activities examined in this study are some variation of aerobic physical activity, which we know from other work can improve cerebral blood flow and strengthen neuronal connections,” he said. “Additional work needs to be done. However, our initial results show that brain aging can be alleviated through an active lifestyle.”

Researchers Find Physiologic Evidence of Chemo Brain
Chemotherapy may induce changes in the brain that may affect concentration and memory. Using PET and CT, researchers detected physiologic evidence of chemo brain, a common side effect in patients undergoing chemotherapy for cancer treatment.

“The chemo brain phenomenon is described as ‘mental fog’ and ‘loss of coping skills’ by patients who receive chemotherapy,” said Rachel A. Lagos, DO, diagnostic radiology resident at the West Virginia University School of Medicine and West Virginia University Hospitals in Morgantown. “Because this is such a common patient complaint, health care providers have generically referred to its occurrence as ‘chemo brain’ for more than two decades.”

Although the complaint may be common, the cause of chemo brain has been difficult to pinpoint. Previous MRI studies have found small changes in brain volume after chemotherapy, but no definitive link has been found.

Instead of studying chemotherapy’s effect on the brain’s appearance, Dr. Lagos and colleagues set out to identify its effect on brain function. By using PET and CT, they were able to assess changes to the brain’s metabolism after chemotherapy.

“When we looked at the results, we were surprised at how obvious the changes were,” Dr. Lagos said. “Chemo brain phenomenon is more than a feeling. It is not depression. It is a change in brain function observable on PET and CT brain imaging.”

Dr. Lagos and colleagues analyzed PET and CT brain imaging results from 128 patients who had undergone chemotherapy for breast cancer. They used special software to help discern differences in brain metabolism before and after chemotherapy. Results were correlated with patient history, neurologic examinations, and chemotherapy regimens.

PET and CT results demonstrated statistically significant decreases in regional brain metabolism that were closely associated with symptoms of chemo brain phenomenon. “The study shows that there are specific areas of the brain that use less energy following chemotherapy,” said Dr. Lagos. “These brain areas are the ones known to be responsible for planning and prioritizing.” PET and CT could possibly be used to facilitate clinical diagnosis and allow for earlier intervention.

Research has already shown that patients with chemo brain can benefit from the assistance of nutritionists, exercise therapists, massage therapists, and counselors. In one study, cancer patients receiving chemotherapy complained of losing their ability to prepare family meals. “When the researchers provided these patients with written and planned menus for each meal, the women were able to buy the groceries, prepare the meals, and enjoy them with their families,” said Dr. Lagos.

Future studies could lead the way to better treatment for patients experiencing this condition. “The next step is to establish a prospective study that begins assessing new patients at the time of cancer diagnosis,” said Dr. Lagos. “The prospective study has the potential to establish an understanding of the change in brain neurotransmitters during chemotherapy, which may lead to improved treatment or prevention.”

Diffusion Tensor Imaging Suggests Brain Compensation After Traumatic Injury
A special MRI technique may be able to predict which patients who have experienced concussions will improve, according to researchers. The results suggest that in some patients, the brain may change to compensate for the damage caused by the injury.

“This finding could lead to strategies for preventing and repairing the damage that accompanies traumatic brain injury [TBI],” said Michael Lipton, MD, PhD, Associate Director of the Gruss Magnetic Resonance Research Center at Albert Einstein College of Medicine of Yeshiva University and Medical Director of MRI Services at Montefiore Medical Center, both in Bronx, New York.

Each year, 1.7 million people in the United States sustain a TBI, according to the CDC. Concussions and other mild TBIs (or mTBIs) account for at least 75% of these injuries. Following a concussion, some patients experience a brief loss of consciousness. Other symptoms include headache, dizziness, memory loss, attention deficit, depression, and anxiety. Some of these conditions may persist for months or years in as many as 30% of patients.

The study involved 17 patients who were admitted to the emergency department at Montefiore and Jacobi Medical Centers and diagnosed with mTBI. Within two weeks of their injuries, the patients underwent diffusion tensor imaging (DTI), which reveals the movement of water molecules within and along axons. DTI allows researchers to measure the uniformity of water movement (fractional anisotropy) throughout the brain. Areas of low fractional anisotropy indicate axonal injury, and areas of abnormally high fractional anisotropy indicate changes in the brain.

“In a TBI, it’s not one specific area that is affected, but multiple areas of the brain that are interconnected by axons,” said Dr. Lipton. “Abnormally low fractional anisotropy within white matter has been correlated with cognitive impairment in concussion patients. We believe that high fractional anisotropy is evidence not of axonal injury, but of brain changes that are occurring in response to the trauma.”

One year after their brain injury, the patients completed two standard questionnaires to assess their postconcussion symptoms and evaluate their health status and quality of life. “Most TBI studies assess cognitive function, but it is not at all clear if and how well such measures assess real-life functioning,” said Dr. Lipton. “Our questionnaires asked about postconcussion symptoms and how those symptoms affected patients’ health and quality of life.”

After comparing the DTI data to the patient questionnaires, the researchers found that abnormally high fractional anisotropy predicted fewer postconcussion symptoms and better functioning. The results suggest that the brain may be actively compensating for its injuries in patients who exhibit areas of high fractional anisotropy on DTI.

“These results could lead to better treatment for concussion if we can find ways to enhance the brain’s compensatory mechanisms,” Dr. Lipton said.

Exercise Rate Related to Improvements in Parkinson’s Disease
People with Parkinson’s disease may benefit from exercise programs on stationary bicycles, and patients who pedal fastest may obtain the greatest benefit. Functional connectivity MRI (fcMRI) data showed that faster pedaling led to greater connectivity in brain areas associated with motor ability.

After Jay L. Alberts, PhD, a neuroscientist at the Cleveland Clinic Lerner Research Institute, rode a tandem bicycle across Iowa with a patient with Parkinson’s disease, the patient experienced improvements in her symptoms.

“The finding was serendipitous,” said Dr. Alberts. “I was pedaling faster than she was, which forced her to pedal faster. She had improvements in her upper extremity function, so we started to look at the possible mechanism behind this improved function.”

As part of this inquiry, Dr. Alberts, researcher Chintan Shah, BS, and their Cleveland Clinic colleagues used fcMRI to study the effect of exercise on 26 patients with Parkinson’s disease.

“By measuring changes in blood oxygenation levels in the brain, fcMRI allows us to look at the functional connectivity between different brain regions,” said Mr. Shah.

The patients underwent bicycle exercise sessions three times per week for eight weeks. Some patients exercised at a voluntary level, and others underwent forced-rate exercise, pedaling at a speed above their voluntary rate. The researchers induced forced-rate activity with a modified exercise bike.

“We developed an algorithm to control a motor on the bike and used a controller to sense the patient’s rate of exertion and adjust the motor based on his or her input,” said Dr. Alberts.

The researchers conducted fcMRI before and after the eight weeks of exercise therapy and again as follow-up four weeks later. The team calculated brain activation and connectivity levels from the fcMRI results and correlated the data with average pedaling rate. Results showed increases in task-related connectivity between the primary motor cortex and the posterior region of the thalamus. Faster pedaling rate was the key factor related to these improvements, which were still evident at follow-up.

“The results show that forced-rate bicycle exercise is an effective, low-cost therapy for Parkinson’s disease,” Mr. Shah said.

Dr. Alberts noted that that while faster pedaling led to more significant results, not all patients with Parkinson’s disease need to do forced-rate exercise to see improvement. “We’re now looking at this phenomenon in patients with exercise bikes in their home, and other exercises like swimming and rowing on tandem machines may provide similar benefits,” he said.

Gender-Based Differences Observed in Alzheimer’s Disease
All patients with Alzheimer’s disease lose brain cells, which leads to atrophy of the brain. However, the pattern of gray matter loss is significantly different between men and women, according to investigators.

“We found that the extent and distribution of regional gray matter volume loss in the brain was strongly influenced by gender,” said lead researcher Maria Vittoria Spampinato, MD, Associate Professor of Radiology at the Medical University of South Carolina in Charleston.

“There is a strong interest in using MRI to assess brain atrophy with the purpose of monitoring dementia progression noninvasively and to aid in understanding which factors can influence brain atrophy progression and distribution in the Alzheimer’s brain,” said Dr. Spampinato.

Dr. Spampinato and colleagues analyzed data on 109 patients, including 60 men and 49 women (mean age, 77), who participated in the Alzheimer’s Disease Neuroimaging Initiative, a major study that followed hundreds of cognitively healthy individuals and patients with mild cognitive impairment (MCI) and Alzheimer’s disease for five years.

During the five-year period, each of the 109 patients progressed from amnestic MCI to Alzheimer’s disease. Using MRI scans of the patients’ brains taken when they were diagnosed with Alzheimer’s disease and 12 months before and after the diagnosis, the researchers created brain maps that illustrated gray matter changes.

The brain maps revealed that, compared with male patients, women had greater atrophy in gray matter 12 months before their Alzheimer’s disease diagnosis and at the time of their diagnosis. The brain maps also showed that men and women in the study lost gray matter volume in different areas of the brain as their disease progressed from MCI to Alzheimer’s disease.

“The female patients in our study initially had more gray matter atrophy than the male patients, but over time, the men caught up,” said Dr. Spampinato. “In the men, the disease developed more aggressively in a shorter period of time.”

The gender differences in atrophy patterns may have important implications for the development of therapies for MCI and Alzheimer’s disease. “These differences should be taken into consideration when testing new drugs in clinical trials,” said Dr. Spampinato. “Knowing the difference between the male and female patterns of atrophy will help researchers better decipher a patient’s response to drug therapy.”

Active Lifestyle May Boost Brain Structure and Slow Alzheimer’s Disease
An active lifestyle may help preserve gray matter in the brains of older adults and could reduce the burden of dementia and Alzheimer’s disease.

To study how an active lifestyle can influence brain structure, Cyrus Raji, MD, PhD, radiology resident at the University of California in Los Angeles, and colleagues examined 876 adults (average age, 78), drawn from the multisite Cardiovascular Health Study. The patients’ condition ranged from normal cognition to Alzheimer’s dementia.

“We had 20 years of clinical data on this group, including BMI and lifestyle habits,” said Dr. Raji. “We drew our patients from four sites across the country, and we were able to assess energy output in the form of kilocalories per week.” The lifestyle factors examined included recreational sports, gardening and yard work, bicycling, dancing, and riding an exercise bicycle.

The researchers used MRI and voxel-based morphometry to model the relationships between energy output and gray matter volume. “Voxel-based morphometry is an advanced method that allows a computer to analyze an MR image and build a mathematical model that helps us to understand the relationship between active lifestyle and gray matter volume,” said Dr. Raji. “Gray matter volume is a key marker of brain health. Larger gray matter volume means a healthier brain. Shrinking volume is seen in Alzheimer’s disease.”

After controlling for age, head size, cognitive impairment, gender, BMI, education, study site location, and white matter disease, the researchers found a strong association between energy output and gray matter volumes in areas of the brain crucial for cognitive function. Greater caloric expenditure was related to larger gray matter volumes in the frontal, temporal, and parietal lobes, including the hippocampus, posterior cingulate, and basal ganglia. There was a strong association between high-energy output and greater gray matter volume in patients with mild cognitive impairment and Alzheimer’s disease.

“Gray matter includes neurons that function in cognition and higher-order cognitive processes,” said Dr. Raji. “The areas of the brain that benefited from an active lifestyle are the ones that consume the most energy and are very sensitive to damage.”

A key aspect of the study was its focus on having variety in lifestyle choices, Dr. Raji noted. “What struck me most about the study results is that it is not one, but a combination of lifestyle choices and activities that benefit the brain,” he said.

The positive influence of an active lifestyle on the brain likely resulted from improved vascular health. “Virtually all of the physical activities examined in this study are some variation of aerobic physical activity, which we know from other work can improve cerebral blood flow and strengthen neuronal connections,” he said. “Additional work needs to be done. However, our initial results show that brain aging can be alleviated through an active lifestyle.”

Researchers Find Physiologic Evidence of Chemo Brain
Chemotherapy may induce changes in the brain that may affect concentration and memory. Using PET and CT, researchers detected physiologic evidence of chemo brain, a common side effect in patients undergoing chemotherapy for cancer treatment.

“The chemo brain phenomenon is described as ‘mental fog’ and ‘loss of coping skills’ by patients who receive chemotherapy,” said Rachel A. Lagos, DO, diagnostic radiology resident at the West Virginia University School of Medicine and West Virginia University Hospitals in Morgantown. “Because this is such a common patient complaint, health care providers have generically referred to its occurrence as ‘chemo brain’ for more than two decades.”

Although the complaint may be common, the cause of chemo brain has been difficult to pinpoint. Previous MRI studies have found small changes in brain volume after chemotherapy, but no definitive link has been found.

Instead of studying chemotherapy’s effect on the brain’s appearance, Dr. Lagos and colleagues set out to identify its effect on brain function. By using PET and CT, they were able to assess changes to the brain’s metabolism after chemotherapy.

“When we looked at the results, we were surprised at how obvious the changes were,” Dr. Lagos said. “Chemo brain phenomenon is more than a feeling. It is not depression. It is a change in brain function observable on PET and CT brain imaging.”

Dr. Lagos and colleagues analyzed PET and CT brain imaging results from 128 patients who had undergone chemotherapy for breast cancer. They used special software to help discern differences in brain metabolism before and after chemotherapy. Results were correlated with patient history, neurologic examinations, and chemotherapy regimens.

PET and CT results demonstrated statistically significant decreases in regional brain metabolism that were closely associated with symptoms of chemo brain phenomenon. “The study shows that there are specific areas of the brain that use less energy following chemotherapy,” said Dr. Lagos. “These brain areas are the ones known to be responsible for planning and prioritizing.” PET and CT could possibly be used to facilitate clinical diagnosis and allow for earlier intervention.

Research has already shown that patients with chemo brain can benefit from the assistance of nutritionists, exercise therapists, massage therapists, and counselors. In one study, cancer patients receiving chemotherapy complained of losing their ability to prepare family meals. “When the researchers provided these patients with written and planned menus for each meal, the women were able to buy the groceries, prepare the meals, and enjoy them with their families,” said Dr. Lagos.

Future studies could lead the way to better treatment for patients experiencing this condition. “The next step is to establish a prospective study that begins assessing new patients at the time of cancer diagnosis,” said Dr. Lagos. “The prospective study has the potential to establish an understanding of the change in brain neurotransmitters during chemotherapy, which may lead to improved treatment or prevention.”