New and Noteworthy Information—December 2014

Two-year folic acid and vitamin B12 supplementation did not improve performance in four cognitive domains in elderly people with elevated homocysteine levels, according to a study published online ahead of print November 12 in Neurology. A total of 2,919 participants with an average age of 74 took either a tablet with 400 μg of folic acid and 500 μg of vitamin B12, or a placebo every day for two years. Tests of memory and thinking skills were performed at the beginning and end of the study. All participants had high blood levels of homocysteine. “While the homocysteine levels decreased by more in the group taking the B vitamins than in the group taking the placebo, unfortunately, there was no difference between the two groups in the scores on the thinking and memory tests,” the researchers stated.

Among more than 43,000 children treated in 25 emergency departments for blunt head trauma, traumatic brain injury (TBI) was identified on CT scans in 7% of the patients, according to a study published November 13 in the New England Journal of Medicine. In children 12 and younger, falls were the most common cause of head injury—among those younger than 2, falls accounted for 77% of head injuries, and in those 2 to 12, falls accounted for 38% of injuries. In children ages 13 to 17, 24% of injuries were due to assault, 19% were sports-related, and 18% resulted from motor vehicle accidents. Among all cases, 98% had mild head trauma. During diagnosis and treatment, cranial CT scans were performed on 37% of the children, “many arguably unnecessarily,” according to the researchers.

Preadmission use of COX-2 inhibitors was associated with increased 30-day mortality after ischemic stroke, but not hemorrhagic stroke, according to a study published online ahead of print November 5 in Neurology. Researchers analyzed records of 100,243 patients hospitalized for a first stroke between 2004 and 2012 and deaths within one month after the stroke. The investigators examined whether participants were current, former, or nonusers of these drugs within two months of the stroke. Overall, people who were current users of COX-2 inhibitors were 19% more likely to die after stroke than were people who did not take the drugs. New users of the older COX-2 drugs were 42% more likely to die from stroke than were those who were not taking the drugs.

Once-daily, low-dose aspirin did not significantly reduce the risk of the composite outcome of cardiovascular death, nonfatal stroke, and nonfatal myocardial infarction among patients age 60 or older with atherosclerotic risk factors, according to a study published online ahead of print November 17 in JAMA. This study included 14,464 Japanese patients with hypertension, dyslipidemia, or diabetes mellitus who were randomized to aspirin (100 mg/d) or no aspirin in addition to ongoing medications. The researchers found no statistically significant difference between the two groups in time to the primary end point. The cumulative primary event rate was similar in participants in the aspirin group (2.77%) and those in the no-aspirin group (2.96%) five years after randomization. Aspirin significantly reduced the incidence of nonfatal heart attack and transient ischemic attack, and significantly increased the risk of extracranial hemorrhage requiring transfusion or hospitalization.

Overall symptom burden is the only independent predictor of prolonged symptoms after sport-related concussion, investigators reported online ahead of print November 7 in Neurology. The researchers conducted a prospective cohort study of 531 patients in a sports concussion clinic. Participants completed questionnaires that included the Post-Concussion Symptom Scale (PCSS). Patients ranged in age from 7 to 26 (mean age, 14.6). The mean PCSS score at the initial visit was 26, and mean time to presentation was 12 days. Only total score on symptom inventory was independently associated with symptoms lasting longer than 28 days. No other potential predictor variables were independently associated with symptom duration or were useful in developing the optimal regression decision tree. Most participants with an initial PCSS score of less than 13 had resolution of their symptoms within 28 days of injury.

The ketogenic diet and modified Atkins diet show modest efficacy, although in some patients the effect is “remarkable” in the treatment of refractory epilepsy in adults, according to a study published online ahead of print October 29 in Neurology. Researchers reviewed five studies on the ketogenic diet that included 47 people and five studies on the modified Atkins diet that included 85 people. The investigators found that across all studies, 32% of people treated with the ketogenic diet and 29% of those treated with the modified Atkins diet had a 50% or better reduction in their seizures. Nine percent in the ketogenic treatment group and 5% in the modified Atkins group had a greater than 90% reduction in seizures. “These studies show the diets are moderately to very effective as another option for people with epilepsy,” stated the study authors.

The evaluation of serum micro-RNAs may help to identify the severity of brain injury and the risk of developing adverse effects after traumatic brain injury (TBI), according to a study published November 7 in PLoS One. Researchers identified a unique and specific group of microRNAs, which were detected in blood immediately after injury to the brain in mice. The results suggest that the microRNAs can be measured in the blood as proxies for mild TBI. The microRNA panel identified in this study is unique and does not overlap with blood microRNAs of post-traumatic stress disorder, as previously reported. “This important finding is a step forward in identifying objective biomarkers for mild TBI that may be further validated to accurately and cost effectively identify mild TBI in service members and civilians with brain injuries,” said the investigators.

The FDA has approved Lemtrada (alemtuzumab) for the treatment of patients with relapsing forms of multiple sclerosis (MS). The approval comes nearly one year after the FDA declined to approve the drug, citing a lack of well-controlled data from clinical studies at the time indicating that the benefits had outweighed the risks. After an appeal by Genzyme (Cambridge, Massachusetts) and a new review by the FDA, the agency approved the drug based on two pivotal, randomized phase III, open-label, rater-blinded studies, comparing treatment with Lemtrada to interferon beta-1a, in patients with relapsing-remitting MS who were either new to treatment (CARE-MS I) or who had relapsed while on prior therapy (CARE-MS II). Lemtrada is recommended for patients who have had an inadequate response to two or more drugs indicated for the treatment of MS.

Angiotensin-converting enzyme inhibitors (ACEIs) exhibited a dose-dependent inverse association with amyotrophic lateral sclerosis (ALS), according to a study published online ahead of print November 10 in JAMA Neurology. Researchers included 729 patients diagnosed with ALS between January 2002 and December 2008. The patients were compared with 14,580 controls. Fifteen percent of patients with ALS reported ACEI use between two and five years before their ALS diagnosis, and 18% of the control group without ALS reported ACEI use. When compared with patients who did not use ACEIs, the adjusted odds ratios were 0.83 for the group prescribed ACEIs lower than 449.5 of the cumulative defined daily dose (cDDD) and 0.43 cDDD for the group with a cumulative ACEI use of greater than 449.5 cDDD.

Patients treated at hospitals with higher volumes of subarachnoid hemorrhage (SAH) cases have lower in-hospital mortality, independent of patient and hospital characteristics, according to a study published in the November Neurosurgery. In a large nationwide registry, researchers identified nearly 32,000 patients with SAH treated at 685 United States hospitals between 2003 and 2012. The median annual case volume per hospital was 8.5 patients. Mean in-hospital mortality was 25.7% but was lower with increasing annual SAH volume. Hospital SAH volume was independently associated with in-hospital mortality (adjusted odds ratio, 0.79 for quartile 4 vs quartile 1), independent of patient and other hospital characteristics. “Our results may have significant implications for regional stroke policies and procedures and affirm the recent recommendations that patients with SAH be treated at high-volume centers,” said study authors.

The use of a specialized ambulance—stroke emergency mobile unit (STEMO)—increases the percentage of patients receiving thrombolysis within 60 minutes, according to a study published online ahead of print November 17 in JAMA Neurology. A total of 3,213 emergency calls for suspected stroke occurred during weeks when STEMO was available, and 2,969 calls occurred during control weeks when STEMO was not available. Two hundred of 614 patients with stroke (32.6%) received thrombolysis when the STEMO was deployed, and 330 of 1,497 patients (22%) received thrombolysis in conventional care. Median onset to treatment was 24.5 minutes shorter after STEMO deployment, compared with conventional care. In all ischemic strokes, the rate of “golden hour” thrombolysis increased from 16 of the 1,497 patients (1.1%) during conventional care to 62 of 614 (10.1%) after STEMO deployment. Overall, golden hour thrombolysis entails no risk to the patients’ safety and is associated with better short-term outcomes, according to the researchers.

Granger causality (GC) analysis of intracranial EEG (iEEG) has the potential to increase understanding of preictal network activity and help improve surgical outcomes in cases of otherwise ambiguous iEEG onset, according to a study published online ahead of print November 4 in Epilepsia. In 10 retrospective and two prospective patients with epilepsy, iEEG was recorded at 500 or 1,000 Hz, using as many as 128 surface and depth electrodes. In all patients, the researchers found significant, widespread preictal GC network activity at peak frequencies from 80 to 250 Hz, beginning two to 42 seconds before visible electrographic onset. In the two prospective patients, GC source/sink comparisons supported the exclusion of early ictal regions that were not the dominant causal sources and contributed to planning of more limited surgical resections. Both groups of patients had a class 1 outcome at one year.

Tiny silent acute infarcts may be a cause of leukoaraiosis, a finding that points toward a potentially treatable form of dementia, investigators reported online ahead of print October 4 in Annals of Neurology. The study involved five patients with leukoaraiosis who underwent detailed MRI scanning of their brains every week for 16 consecutive weeks. The MRI scans revealed new tiny spots arising de novo in the cerebral white matter. The lesions were “clinically silent and had the signature features of acute ischemic stroke, according to the researchers. “With time, the characteristics of these lesions approached those of pre-existing leukoaraiosis,” the study authors stated.

—Kimberly D. Williams

Two-year folic acid and vitamin B12 supplementation did not improve performance in four cognitive domains in elderly people with elevated homocysteine levels, according to a study published online ahead of print November 12 in Neurology. A total of 2,919 participants with an average age of 74 took either a tablet with 400 μg of folic acid and 500 μg of vitamin B12, or a placebo every day for two years. Tests of memory and thinking skills were performed at the beginning and end of the study. All participants had high blood levels of homocysteine. “While the homocysteine levels decreased by more in the group taking the B vitamins than in the group taking the placebo, unfortunately, there was no difference between the two groups in the scores on the thinking and memory tests,” the researchers stated.

Among more than 43,000 children treated in 25 emergency departments for blunt head trauma, traumatic brain injury (TBI) was identified on CT scans in 7% of the patients, according to a study published November 13 in the New England Journal of Medicine. In children 12 and younger, falls were the most common cause of head injury—among those younger than 2, falls accounted for 77% of head injuries, and in those 2 to 12, falls accounted for 38% of injuries. In children ages 13 to 17, 24% of injuries were due to assault, 19% were sports-related, and 18% resulted from motor vehicle accidents. Among all cases, 98% had mild head trauma. During diagnosis and treatment, cranial CT scans were performed on 37% of the children, “many arguably unnecessarily,” according to the researchers.

Preadmission use of COX-2 inhibitors was associated with increased 30-day mortality after ischemic stroke, but not hemorrhagic stroke, according to a study published online ahead of print November 5 in Neurology. Researchers analyzed records of 100,243 patients hospitalized for a first stroke between 2004 and 2012 and deaths within one month after the stroke. The investigators examined whether participants were current, former, or nonusers of these drugs within two months of the stroke. Overall, people who were current users of COX-2 inhibitors were 19% more likely to die after stroke than were people who did not take the drugs. New users of the older COX-2 drugs were 42% more likely to die from stroke than were those who were not taking the drugs.

Once-daily, low-dose aspirin did not significantly reduce the risk of the composite outcome of cardiovascular death, nonfatal stroke, and nonfatal myocardial infarction among patients age 60 or older with atherosclerotic risk factors, according to a study published online ahead of print November 17 in JAMA. This study included 14,464 Japanese patients with hypertension, dyslipidemia, or diabetes mellitus who were randomized to aspirin (100 mg/d) or no aspirin in addition to ongoing medications. The researchers found no statistically significant difference between the two groups in time to the primary end point. The cumulative primary event rate was similar in participants in the aspirin group (2.77%) and those in the no-aspirin group (2.96%) five years after randomization. Aspirin significantly reduced the incidence of nonfatal heart attack and transient ischemic attack, and significantly increased the risk of extracranial hemorrhage requiring transfusion or hospitalization.

Overall symptom burden is the only independent predictor of prolonged symptoms after sport-related concussion, investigators reported online ahead of print November 7 in Neurology. The researchers conducted a prospective cohort study of 531 patients in a sports concussion clinic. Participants completed questionnaires that included the Post-Concussion Symptom Scale (PCSS). Patients ranged in age from 7 to 26 (mean age, 14.6). The mean PCSS score at the initial visit was 26, and mean time to presentation was 12 days. Only total score on symptom inventory was independently associated with symptoms lasting longer than 28 days. No other potential predictor variables were independently associated with symptom duration or were useful in developing the optimal regression decision tree. Most participants with an initial PCSS score of less than 13 had resolution of their symptoms within 28 days of injury.

The ketogenic diet and modified Atkins diet show modest efficacy, although in some patients the effect is “remarkable” in the treatment of refractory epilepsy in adults, according to a study published online ahead of print October 29 in Neurology. Researchers reviewed five studies on the ketogenic diet that included 47 people and five studies on the modified Atkins diet that included 85 people. The investigators found that across all studies, 32% of people treated with the ketogenic diet and 29% of those treated with the modified Atkins diet had a 50% or better reduction in their seizures. Nine percent in the ketogenic treatment group and 5% in the modified Atkins group had a greater than 90% reduction in seizures. “These studies show the diets are moderately to very effective as another option for people with epilepsy,” stated the study authors.

The evaluation of serum micro-RNAs may help to identify the severity of brain injury and the risk of developing adverse effects after traumatic brain injury (TBI), according to a study published November 7 in PLoS One. Researchers identified a unique and specific group of microRNAs, which were detected in blood immediately after injury to the brain in mice. The results suggest that the microRNAs can be measured in the blood as proxies for mild TBI. The microRNA panel identified in this study is unique and does not overlap with blood microRNAs of post-traumatic stress disorder, as previously reported. “This important finding is a step forward in identifying objective biomarkers for mild TBI that may be further validated to accurately and cost effectively identify mild TBI in service members and civilians with brain injuries,” said the investigators.

The FDA has approved Lemtrada (alemtuzumab) for the treatment of patients with relapsing forms of multiple sclerosis (MS). The approval comes nearly one year after the FDA declined to approve the drug, citing a lack of well-controlled data from clinical studies at the time indicating that the benefits had outweighed the risks. After an appeal by Genzyme (Cambridge, Massachusetts) and a new review by the FDA, the agency approved the drug based on two pivotal, randomized phase III, open-label, rater-blinded studies, comparing treatment with Lemtrada to interferon beta-1a, in patients with relapsing-remitting MS who were either new to treatment (CARE-MS I) or who had relapsed while on prior therapy (CARE-MS II). Lemtrada is recommended for patients who have had an inadequate response to two or more drugs indicated for the treatment of MS.

Angiotensin-converting enzyme inhibitors (ACEIs) exhibited a dose-dependent inverse association with amyotrophic lateral sclerosis (ALS), according to a study published online ahead of print November 10 in JAMA Neurology. Researchers included 729 patients diagnosed with ALS between January 2002 and December 2008. The patients were compared with 14,580 controls. Fifteen percent of patients with ALS reported ACEI use between two and five years before their ALS diagnosis, and 18% of the control group without ALS reported ACEI use. When compared with patients who did not use ACEIs, the adjusted odds ratios were 0.83 for the group prescribed ACEIs lower than 449.5 of the cumulative defined daily dose (cDDD) and 0.43 cDDD for the group with a cumulative ACEI use of greater than 449.5 cDDD.

Patients treated at hospitals with higher volumes of subarachnoid hemorrhage (SAH) cases have lower in-hospital mortality, independent of patient and hospital characteristics, according to a study published in the November Neurosurgery. In a large nationwide registry, researchers identified nearly 32,000 patients with SAH treated at 685 United States hospitals between 2003 and 2012. The median annual case volume per hospital was 8.5 patients. Mean in-hospital mortality was 25.7% but was lower with increasing annual SAH volume. Hospital SAH volume was independently associated with in-hospital mortality (adjusted odds ratio, 0.79 for quartile 4 vs quartile 1), independent of patient and other hospital characteristics. “Our results may have significant implications for regional stroke policies and procedures and affirm the recent recommendations that patients with SAH be treated at high-volume centers,” said study authors.

The use of a specialized ambulance—stroke emergency mobile unit (STEMO)—increases the percentage of patients receiving thrombolysis within 60 minutes, according to a study published online ahead of print November 17 in JAMA Neurology. A total of 3,213 emergency calls for suspected stroke occurred during weeks when STEMO was available, and 2,969 calls occurred during control weeks when STEMO was not available. Two hundred of 614 patients with stroke (32.6%) received thrombolysis when the STEMO was deployed, and 330 of 1,497 patients (22%) received thrombolysis in conventional care. Median onset to treatment was 24.5 minutes shorter after STEMO deployment, compared with conventional care. In all ischemic strokes, the rate of “golden hour” thrombolysis increased from 16 of the 1,497 patients (1.1%) during conventional care to 62 of 614 (10.1%) after STEMO deployment. Overall, golden hour thrombolysis entails no risk to the patients’ safety and is associated with better short-term outcomes, according to the researchers.

Granger causality (GC) analysis of intracranial EEG (iEEG) has the potential to increase understanding of preictal network activity and help improve surgical outcomes in cases of otherwise ambiguous iEEG onset, according to a study published online ahead of print November 4 in Epilepsia. In 10 retrospective and two prospective patients with epilepsy, iEEG was recorded at 500 or 1,000 Hz, using as many as 128 surface and depth electrodes. In all patients, the researchers found significant, widespread preictal GC network activity at peak frequencies from 80 to 250 Hz, beginning two to 42 seconds before visible electrographic onset. In the two prospective patients, GC source/sink comparisons supported the exclusion of early ictal regions that were not the dominant causal sources and contributed to planning of more limited surgical resections. Both groups of patients had a class 1 outcome at one year.

Tiny silent acute infarcts may be a cause of leukoaraiosis, a finding that points toward a potentially treatable form of dementia, investigators reported online ahead of print October 4 in Annals of Neurology. The study involved five patients with leukoaraiosis who underwent detailed MRI scanning of their brains every week for 16 consecutive weeks. The MRI scans revealed new tiny spots arising de novo in the cerebral white matter. The lesions were “clinically silent and had the signature features of acute ischemic stroke, according to the researchers. “With time, the characteristics of these lesions approached those of pre-existing leukoaraiosis,” the study authors stated.

—Kimberly D. Williams

Two-year folic acid and vitamin B12 supplementation did not improve performance in four cognitive domains in elderly people with elevated homocysteine levels, according to a study published online ahead of print November 12 in Neurology. A total of 2,919 participants with an average age of 74 took either a tablet with 400 μg of folic acid and 500 μg of vitamin B12, or a placebo every day for two years. Tests of memory and thinking skills were performed at the beginning and end of the study. All participants had high blood levels of homocysteine. “While the homocysteine levels decreased by more in the group taking the B vitamins than in the group taking the placebo, unfortunately, there was no difference between the two groups in the scores on the thinking and memory tests,” the researchers stated.

Among more than 43,000 children treated in 25 emergency departments for blunt head trauma, traumatic brain injury (TBI) was identified on CT scans in 7% of the patients, according to a study published November 13 in the New England Journal of Medicine. In children 12 and younger, falls were the most common cause of head injury—among those younger than 2, falls accounted for 77% of head injuries, and in those 2 to 12, falls accounted for 38% of injuries. In children ages 13 to 17, 24% of injuries were due to assault, 19% were sports-related, and 18% resulted from motor vehicle accidents. Among all cases, 98% had mild head trauma. During diagnosis and treatment, cranial CT scans were performed on 37% of the children, “many arguably unnecessarily,” according to the researchers.

Preadmission use of COX-2 inhibitors was associated with increased 30-day mortality after ischemic stroke, but not hemorrhagic stroke, according to a study published online ahead of print November 5 in Neurology. Researchers analyzed records of 100,243 patients hospitalized for a first stroke between 2004 and 2012 and deaths within one month after the stroke. The investigators examined whether participants were current, former, or nonusers of these drugs within two months of the stroke. Overall, people who were current users of COX-2 inhibitors were 19% more likely to die after stroke than were people who did not take the drugs. New users of the older COX-2 drugs were 42% more likely to die from stroke than were those who were not taking the drugs.

Once-daily, low-dose aspirin did not significantly reduce the risk of the composite outcome of cardiovascular death, nonfatal stroke, and nonfatal myocardial infarction among patients age 60 or older with atherosclerotic risk factors, according to a study published online ahead of print November 17 in JAMA. This study included 14,464 Japanese patients with hypertension, dyslipidemia, or diabetes mellitus who were randomized to aspirin (100 mg/d) or no aspirin in addition to ongoing medications. The researchers found no statistically significant difference between the two groups in time to the primary end point. The cumulative primary event rate was similar in participants in the aspirin group (2.77%) and those in the no-aspirin group (2.96%) five years after randomization. Aspirin significantly reduced the incidence of nonfatal heart attack and transient ischemic attack, and significantly increased the risk of extracranial hemorrhage requiring transfusion or hospitalization.

Overall symptom burden is the only independent predictor of prolonged symptoms after sport-related concussion, investigators reported online ahead of print November 7 in Neurology. The researchers conducted a prospective cohort study of 531 patients in a sports concussion clinic. Participants completed questionnaires that included the Post-Concussion Symptom Scale (PCSS). Patients ranged in age from 7 to 26 (mean age, 14.6). The mean PCSS score at the initial visit was 26, and mean time to presentation was 12 days. Only total score on symptom inventory was independently associated with symptoms lasting longer than 28 days. No other potential predictor variables were independently associated with symptom duration or were useful in developing the optimal regression decision tree. Most participants with an initial PCSS score of less than 13 had resolution of their symptoms within 28 days of injury.

The ketogenic diet and modified Atkins diet show modest efficacy, although in some patients the effect is “remarkable” in the treatment of refractory epilepsy in adults, according to a study published online ahead of print October 29 in Neurology. Researchers reviewed five studies on the ketogenic diet that included 47 people and five studies on the modified Atkins diet that included 85 people. The investigators found that across all studies, 32% of people treated with the ketogenic diet and 29% of those treated with the modified Atkins diet had a 50% or better reduction in their seizures. Nine percent in the ketogenic treatment group and 5% in the modified Atkins group had a greater than 90% reduction in seizures. “These studies show the diets are moderately to very effective as another option for people with epilepsy,” stated the study authors.

The evaluation of serum micro-RNAs may help to identify the severity of brain injury and the risk of developing adverse effects after traumatic brain injury (TBI), according to a study published November 7 in PLoS One. Researchers identified a unique and specific group of microRNAs, which were detected in blood immediately after injury to the brain in mice. The results suggest that the microRNAs can be measured in the blood as proxies for mild TBI. The microRNA panel identified in this study is unique and does not overlap with blood microRNAs of post-traumatic stress disorder, as previously reported. “This important finding is a step forward in identifying objective biomarkers for mild TBI that may be further validated to accurately and cost effectively identify mild TBI in service members and civilians with brain injuries,” said the investigators.

The FDA has approved Lemtrada (alemtuzumab) for the treatment of patients with relapsing forms of multiple sclerosis (MS). The approval comes nearly one year after the FDA declined to approve the drug, citing a lack of well-controlled data from clinical studies at the time indicating that the benefits had outweighed the risks. After an appeal by Genzyme (Cambridge, Massachusetts) and a new review by the FDA, the agency approved the drug based on two pivotal, randomized phase III, open-label, rater-blinded studies, comparing treatment with Lemtrada to interferon beta-1a, in patients with relapsing-remitting MS who were either new to treatment (CARE-MS I) or who had relapsed while on prior therapy (CARE-MS II). Lemtrada is recommended for patients who have had an inadequate response to two or more drugs indicated for the treatment of MS.

Angiotensin-converting enzyme inhibitors (ACEIs) exhibited a dose-dependent inverse association with amyotrophic lateral sclerosis (ALS), according to a study published online ahead of print November 10 in JAMA Neurology. Researchers included 729 patients diagnosed with ALS between January 2002 and December 2008. The patients were compared with 14,580 controls. Fifteen percent of patients with ALS reported ACEI use between two and five years before their ALS diagnosis, and 18% of the control group without ALS reported ACEI use. When compared with patients who did not use ACEIs, the adjusted odds ratios were 0.83 for the group prescribed ACEIs lower than 449.5 of the cumulative defined daily dose (cDDD) and 0.43 cDDD for the group with a cumulative ACEI use of greater than 449.5 cDDD.

Patients treated at hospitals with higher volumes of subarachnoid hemorrhage (SAH) cases have lower in-hospital mortality, independent of patient and hospital characteristics, according to a study published in the November Neurosurgery. In a large nationwide registry, researchers identified nearly 32,000 patients with SAH treated at 685 United States hospitals between 2003 and 2012. The median annual case volume per hospital was 8.5 patients. Mean in-hospital mortality was 25.7% but was lower with increasing annual SAH volume. Hospital SAH volume was independently associated with in-hospital mortality (adjusted odds ratio, 0.79 for quartile 4 vs quartile 1), independent of patient and other hospital characteristics. “Our results may have significant implications for regional stroke policies and procedures and affirm the recent recommendations that patients with SAH be treated at high-volume centers,” said study authors.

The use of a specialized ambulance—stroke emergency mobile unit (STEMO)—increases the percentage of patients receiving thrombolysis within 60 minutes, according to a study published online ahead of print November 17 in JAMA Neurology. A total of 3,213 emergency calls for suspected stroke occurred during weeks when STEMO was available, and 2,969 calls occurred during control weeks when STEMO was not available. Two hundred of 614 patients with stroke (32.6%) received thrombolysis when the STEMO was deployed, and 330 of 1,497 patients (22%) received thrombolysis in conventional care. Median onset to treatment was 24.5 minutes shorter after STEMO deployment, compared with conventional care. In all ischemic strokes, the rate of “golden hour” thrombolysis increased from 16 of the 1,497 patients (1.1%) during conventional care to 62 of 614 (10.1%) after STEMO deployment. Overall, golden hour thrombolysis entails no risk to the patients’ safety and is associated with better short-term outcomes, according to the researchers.

Granger causality (GC) analysis of intracranial EEG (iEEG) has the potential to increase understanding of preictal network activity and help improve surgical outcomes in cases of otherwise ambiguous iEEG onset, according to a study published online ahead of print November 4 in Epilepsia. In 10 retrospective and two prospective patients with epilepsy, iEEG was recorded at 500 or 1,000 Hz, using as many as 128 surface and depth electrodes. In all patients, the researchers found significant, widespread preictal GC network activity at peak frequencies from 80 to 250 Hz, beginning two to 42 seconds before visible electrographic onset. In the two prospective patients, GC source/sink comparisons supported the exclusion of early ictal regions that were not the dominant causal sources and contributed to planning of more limited surgical resections. Both groups of patients had a class 1 outcome at one year.

Tiny silent acute infarcts may be a cause of leukoaraiosis, a finding that points toward a potentially treatable form of dementia, investigators reported online ahead of print October 4 in Annals of Neurology. The study involved five patients with leukoaraiosis who underwent detailed MRI scanning of their brains every week for 16 consecutive weeks. The MRI scans revealed new tiny spots arising de novo in the cerebral white matter. The lesions were “clinically silent and had the signature features of acute ischemic stroke, according to the researchers. “With time, the characteristics of these lesions approached those of pre-existing leukoaraiosis,” the study authors stated.

—Kimberly D. Williams