Peyman Shirani

Medical and environmental risk factors associated with frontotemporal dementia: A case-control study in a veteran population

Compared with other major dementias, very little is known about the medical and environmental risk factors associated with frontotemporal dementia (FTD). In this study, we evaluated medical and environmental disorders associated with FTD in a veteran population.

Severity of Hypoperfusion in Distinct Brain Regions Predicts Severity of Hemispatial Neglect in Different Reference Frames

Background and Purpose— Hemispatial neglect is among the most common and disabling consequences of right hemisphere stroke. A variety of variables have been associated with the presence or severity of neglect but have not evaluated the independent effects of location, severity, and volume of ischemia. Few have determined areas involved in different types of neglect. We identified the contributions of these variables to severity of viewer-centered versus stimulus-centered neglect in acute ischemic right hemisphere stroke. Methods— We studied 137 patients within 24 hours of stroke onset with MR diffusion- and perfusion-weighted imaging and a test of hemispatial neglect that distinguishes between viewer-centered and stimulus-centered neglect. Using multivariable linear regression, we identified the independent contributions of severity of ischemia in specific locations, volume of ischemia, and age in accounting for severity of each neglect type. Results— Severity of hypoperfusion in angular gyrus was the only variable that significantly and independently contributed to severity of viewer-centered neglect. Volume of dysfunctional tissue and hypoperfusion in posterior frontal cortex also accounted for some variability in severity of viewer-centered neglect. Severity of hypoperfusion of superior temporal cortex was the only variable that independently and significantly contributed to severity of stimulus-centered neglect. Conclusions— Location, severity, and volume of ischemia together determine the type and severity of neglect after right hemisphere stroke. Results also show that perfusion-weighted MRI can be used as a semiquantitative measure of tissue dysfunction in acute stroke and can account for a substantial proportion of the variability in functional deficits in the acute stage.

Is acute reperfusion therapy safe in acute ischemic stroke patients who harbor unruptured intracranial aneurysm

Background Intracranial aneurysms are currently considered as contraindication for intravenous thrombolysis in acute ischemic stroke, very likely due to a possible increase in the risk of bleeding from aneurysm rupture; however, there is limited data available on whether intravenous thrombolysis is safe for acute ischemic stroke patients with pre-existing intracranial aneurysms. Aims and/or hypothesis To find out the safety of intravenous thrombolysis in acute ischemic stroke patients who harbor unruptured intracranial aneurysms. Methods We retrospectively reviewed the medical records and cerebrovascular images of all the patients treated with intravenous thrombolysis for acute ischemic stroke in our center from the beginning of 2006 till the end of April 2014. Those with unruptured intracranial aneurysm present on cerebrovascular images prior to acute reperfusion therapy were identified. Post-thrombolysis brain imaging was reviewed to evaluate for any intraparenchymal or subarachnoid hemorrhage related or unrelated to the aneurysm. Results A total of 637 patients received intravenous thrombolysis for acute ischemic stroke in our center during an 8.3-year period. Thirty-three (5.2%) were found to have at least one intracranial aneurysms. Twenty-three (70%) of those received only intravenous thrombolysis, and 10 patients received combination of intravenous and intra-arterial throm-bolysis. The size of the largest aneurysm was 10 mm in maximum diameter (range: 2-10 mm). The mean size of aneurysms was 4.8 mm. No symptomatic intracranial hemorrhage occurred among the 23 patients receiving only intravenous thrombolysis. Out of those who received a combination of intravenous and intra-arterial thrombolysis, one developed symptomatic intracranial hemorrhage in the location of acute infarct, distant to the aneurysm location. Conclusion Our findings suggest that neither intravenous thrombolysis nor combination of intravenous and intra-arterial thrombolysis increases the risk of aneurysmal hemorrhage in acute ischemic stroke patients who harbor unruptured intracranial aneurysms less than 10 mm in diameter. Their listing in exclusion criteria for intravenous throm-bolysis should be reconsidered to assure appropriate use of acute reperfusion therapy in this group of patients.

Vein of Galen malformation treated with the Micro Vascular Plug system: case report

This case report describes the use of the Micro Vascular Plug (MVP) system in a mural-type vein of Galen aneurysmal malformation, resulting in successful occlusion of the cerebrovascular fistula. This result was confirmed with immediate cessation in blood flow and 6-month follow-up angiography. The unique characteristics of the MVP provide potential advantages over current embolic techniques for occlusion of high-flow, fistulous, intracranial vessels such as those seen in the vein of Galen aneurysmal malformation, and may represent a valuable addition to the currently available options.

Safety of intravenous thrombolysis for acute ischemic stroke in patients with preexisting intracranial neoplasms: a case series

Intracranial neoplasms are currently considered a contraindication for intravenous (IV) thrombolysis in acute ischemic stroke (AIS) patients (1,2). Minimal data are available on the safety of IV thrombolysis for AIS in patients with preexisting intracranial neoplasm. We sought to determine the safety of IV recombitant tissue plasminogen activator (rtPA) in such patients through a retrospective hospital-based study. We retrospectively reviewed the medical records of patients who received IV rtPA for AIS from January 2006 to April 2014 at our tertiary academic medical center. All patients were treated based on the standard protocol adopted from the American Heart Association/ American Stroke Association within 4.5 h of AIS onset (2). Patients who received intra-arterial (IA) thrombolysis after IV rtPA were included. A subset of patients with definite intracranial neoplasms from this cohort was identified. Follow-up computed tomography (CT) or magnetic resonance imaging (MRI) within 24 to 36 h of IV rtPA administration and medical records were reviewed to determine the number of patients with symptomatic intracranial hemorrhage (sICH) in this subset. sICH was defined as intracranial hemorrhage (ICH) with an increase in National Institutes of Health Stroke Scale of at least 4 points (3). In addition, hemorrhage within the neoplasm was evaluated. Six hundred thirty-seven patients received full dose IV rtPA for AIS within the study period. Preexisting intracranial neoplasms were found in 13 of the 637 patients reviewed (2%). The demographics of the patients are outlined in Table 1. None of the 13 patients developed sICH or hemorrhage into the tumor after thrombolysis. To the best of our knowledge, our study is the largest on the safety of IV rtPA for AIS in patients with preexisting intracranial neoplasms. This study is also the first report, to our knowledge, of patients with intracranial neoplasm who received IV rtPA followed by IA thrombolysis with mechanical thrombectomy devices. Our study should be interpreted in light of several limitations. It is a single-center study with a low number of cases; in addition, we have no malignant neoplasm in our cohort and no generally valid conclusion can be drawn about the safety of IV thrombolysis in all grades of intracranial neoplasm. Our finding suggests that IV rtPA administration for AIS does not increase the risk of hemorrhage within the neoplasm in patients with preexisting benign intracranial neoplasm. Their listing in exclusion criteria for rtPA should be reconsidered to assure appropriate use of IV rtPA in this group of patients. We hope our study will encourage other centers to look into their data and study this further, so as to determine the actual risk of hemorrhage with rtPA in patients with intracranial neoplasms.

Lumbar Puncture Alleviates Chorea in a Patient with Huntington’s Disease and Normal Pressure Hydrocephalus

A 44-year-old African-American male was admitted to our hospital after a suicide attempt. He had depression, poor cognitive function, choreiform movements, difficulty pronouncing words, and difficulty walking. His symptoms had worsened markedly over several months. Chorea lead to genetic testing that confirmed a diagnosis of Huntington Disease (HD). A CT scan of the head showed wider ventricles than is typical of HD. The head CT and gait change suggested normal pressure hydrocephalus (NPH). Lumbar puncture (LP) led to improved neuropsychologic test scores and walking thereby supporting the diagnosis of NPH. Surprisingly, the LP also led to an 80% improvement of chorea. There are two other reports of an association between HD and NPH. NPH should be considered in HD patients with atypical symptoms, such as the inability to walk or rapid progression, as its treatment may lead to improved cognition, gait, and chorea.

Delays in door-to-needle time for acute ischemic stroke in the emergency department: A comprehensive stroke center experience

BACKGROUND Current American Stroke Association guidelines recommend initiating intravenous thrombolysis (IVT) for acute ischemic stroke (AIS) within 60min of patient arrival, given the benefits of IVT for AIS are time dependent. This study aimed to identify the delaying factors in door-to-needle time (DTN) in the emergency department of one of the largest comprehensive stroke centers in New York State. We also recommended measures to reduce the delays. METHODS We retrospectively reviewed the medical charts of all AIS patients who received IVT in our emergency department patients between April 1, 2012 and December 31, 2015 to identify those with a DTN time of >60min. We categorized the factors causing the delay into different groups. For each group, we recommended measures to reduce the treatment delays. RESULTS A total of 487 patients received IVT for AIS during the 3.7-year period. Of these, 96 patients (20.4%) met our DTN time delay criteria. Delays for obtaining stroke imaging and hypertension control were the most common factors. Thirty eight patients (39.5%) had delay in obtaining CT-based stroke imaging. Twenty-two patients (22.9%) required control of elevated blood pressure prior to IVT. Other causes for delay in DTN time included delay in stroke triage and paging (11.4%), fluctuating neurological symptoms (7.2%), uncertainty about diagnosis (12.5%), delays associated with obtaining consent (9.3%), and uncertainty about the time of symptom onset (5.2%). CONCLUSION Important and common causes of delay in IVT for AIS were identified in a review of charts at our comprehensive stroke center. The authors recommend strategies to achieve faster DTN time for each of the delaying factor categories including faster acquisition and interpretation of stroke imaging, more effective triage protocols and faster blood pressure control for AIS patients who are eligible for IVT.

Intravenous Thrombolysis for Acute Ischemic Stroke in Patients with Thrombocytopenia

OBJECTIVE To determine the safety of intravenous (IV) recombinant tissue plasminogen activator (rtPA) in patients with acute ischemic stroke (AIS) who had a platelet count <100,000 /mm3. METHODS We reviewed the charts of all patients who received IV rtPA for AIS during a 9.6-year period at our stroke center. Those with platelets <100,000/mm3 were identified. Head computed tomography scans performed in 24-36 hours postthrombolysis were reviewed to evaluate the rate of symptomatic intracranial hemorrhage (sICH). RESULTS A total of 835 patients received IV rtPA for AIS during this period. A total of 5 patients were identified to have a platelet count <100,000/mm3. One of them (20%) developed sICH post-IV tPA administration .The mean platelet count of those 5 patients was 63,000 ± 19,000/mm3. To the best of our knowledge, only 21 thrombocytopenic patients have been reported to receive IV rtPA for AIS in the medical literature. Combining our 5 cases with 21 patients previously reported, we have 26 AIS patients who had a platelet count <100,000/mm3 and received IV rtPA, with 2 of them developing sICH (7.7 %). Comparing the rate of sICH among this group with the patients with normal platelet count in our cohort, there was no statistically significant difference (7.7% versus 6.04%, P value = .73). CONCLUSION IV rtPA for AIS might be safe in patients with platelet count <100,000/mm3 and it is reasonable not to delay IV rtPA administration while waiting for the platelet count result, unless there is strong suspicion for abnormal platelet count.

The Role of Catheter Angiography in the Diagnosis of Central Nervous System Vasculitis

Background: Central nervous system vasculitis (CNSV) is a rare disorder, the pathophysiology of which is not fully understood. It involves a combination of inflammation and thrombosis. CNSV is most commonly associated with headache, gradual changes in mental status, and focal neurological symptoms. Diagnosis requires the effective use of history, laboratory testing, imaging, and biopsy. Catheter angiography can be a powerful tool in the diagnosis when common and low-frequency angiographic manifestations of CNSV are considered. We review these manifestations and their place in the diagnostic algorithm of CNSV. Summary: We reviewed the PubMed database for case series of CNSV that included 5 or more patients. Demographic and angiographic findings were collected. Angiographic findings were dichotomized between common and low-frequency findings. A system for incorporating these findings into clinical decision-making is proposed. Key Message: CNSV is a diagnostic challenge due to the absence of a true gold standard test. In the absence of such a test, catheter angiography remains a central piece of the diagnostic puzzle when appropriately employed and interpreted.

CNS aspergillosis in a patient with Crohn's disease on immunosuppressants: a case report

Fungal infections of the central nervous system are an uncommon cause of rapid decline in consciousness. We describe the case of central nervous system aspergillosis in a patient on immunosupressants whose clinical course highlights the need for an aggressive approach to diagnosis.