Cerebral microinfarcts disruption of remote cortical thickness.

INTRODUCTION: Cerebral microinfarcts (CMI) are common lesions, carrying an important contribution to small-vessel-related cognitive impairment. CMIs were previously found to cause local microstructural damage and disruption of white matter integrity. This study examines CMIs influence on cortical thickness in remote brain areas. METHODS: Six small silent diffuse weighted imaging (DWI) lesions corresponding to subacute CMI were identified among five patients who underwent baseline and follow-up MRI scans from the Tel-Aviv Acute Brain Stroke Cohort (TABASCO). Regions of interest (ROIs) corresponding to the site of the DWI lesions and of the non-lesioned contralateral hemisphere (control ROI) were co-registered. DTI tractography was additionally performed to reconstruct the white matter tracts containing the ROIs. The normalized cortical thickness was calculated for the DWI lesional tract as well as for the contralateral non-lesional tract, and the lesion-to-control cortical thickness ratio (CTR) was calculated. RESULTS: Post-lesional scans, performed 25.1 ± 1.2 months after CMI detection, demonstrated reduced mean CTR within the ROI from 1.8 to 1.1 (p = 0.032). There was no difference between the CTR of the right hemisphere relative to those on the left hemisphere, or between the CTR change of the cortical and non-cortical CMI. DISCUSSION: This study demonstrated the prolonged influence of CMI on cortical thickness in remote ROI. The total number of CMIs is difficult to determine, however it has been shown that detecting even a single CMI suggests the existence of hundreds to thousands lesions. Therefore, the cumulative impact of these widely distributed lesions on cerebral cortex may have a significant contribution to the development of vascular cognitive impairment.

Practice recommendations for neurovascular ultrasound investigations of acute stroke patients in the setting of the COVID-19 pandemic: an expert consensus from the European Society of Neurosonology and Cerebral Hemodynamics.

BACKGROUND AND PURPOSE: Patients with acute ischemic stroke are at high-risk for contracting COVID-19 infection. Additionally, healthcare professionals including neurovascular ultrasound providers are also at risk of being infected by SARS-CoV-2 virus. Yet, preparedness to continue to guarantee hyperacute treatment is vital for patients outcome. In light of this situation, the European Society of Neurosonology and Cerebral Hemodynamic (ESNCH) appointed a task force to provide consensus recommendations for the performance of neurovascular ultrasound investigations in acute ischemic stroke during the COVID-19 pandemic with the aim of protecting both patients and ultrasound providers. METHODS: The "ultrasound in acute stroke working group" of the ESNCH examined literature articles and reviews using the following key words: "corona virus" or "COVID-19" or "SARS-CoV-2 virus", and "acute stroke" or "cerebrovascular disease", and "ultrasound". Thereafter, a thorough discussion was conducted with the "education and guidelines working group" of the ESNCH. RESULTS: We propose rapid up-to-date recommendations for healthcare personnel involved in the pre-hospital and intra-hospital assessment of stroke patients, with a particular attention to neurovascular ultrasound performance. CONCLUSION: The ESNCH provides a guidance summary for the performance of neurovascular ultrasound investigations in acute ischemic stroke in the time of COVID-19.

Clinical and radiological determinants of transient symptoms associated with infarction (TSI).

BACKGROUND: The definition of transient ischemic attack was traditionally based on clinical features only. The wide use of magnetic resonance imaging (MRI) led to the definition of a new entity - transient symptoms associated with infarction (TSI). It is unclear why patients with similar radiological infarctions may have different clinical manifestation - ranging from complete symptoms resolution to major neurological sequelae. We sought to determine which factors differentiate acute diffuse weighted imaging (DWI) lesion presentation - stroke versus TSI. METHODS: 282 Participants, recruited for the Tel-Aviv Brain Acute Stroke Cohort study (TABASCO), were enrolled consecutively. Participants underwent extensive cognitive evaluation, wide laboratory tests and brain MRI scans evaluated for cerebral small vessel disease (SVD) biomarkers, according to the STRIVE protocol. Demographic and clinical characteristics were also examined. RESULTS: A total of 239 patients had stroke and 43 patients had TSI. TSI patients had smaller average lesion volume (0.77 cm3 versus 2.64 cm3, p = 0.002). Lesion location did not differentiate TSI and stroke. Stroke patients had elevated inflammatory markers, unrelated to lesion size (CRP 4.2 mg/L versus 1.7 mg/L, p = 0.011). TSI patients had better global cognitive score and MoCA score at admission and 24 months following the index event (p < 0.001). TSI patients also had better Berg balance score (p = 0.004). No significant association was found with MRI SVD markers. CONCLUSIONS: Lesion size, but not location, differentiates TSI and stroke, especially at a cutoff value of 10 cm3. Elevated inflammatory response was linked to worse course independently of lesion volume. Cognitive and high function tests are associated to the clinical phenotype of ischemic lesion and may be a marker of brain reserve and compensatory abilities. SVD markers do not differ between TSI and stroke patients and probably do not fully capture the extent of brain vascular pathology and reserve.

High hair cortisol concentrations predict worse cognitive outcome after stroke: Results from the TABASCO prospective cohort study.

BACKGROUND AND PURPOSE: The role of stress-related endocrine dysregulation in the development of cognitive changes following a stroke needs further elucidation. We explored this issue in a longitudinal study on stroke survivors using hair cortisol concentrations (HCC), a measure of integrated long-term cortisol levels. METHODS: Participants were consecutive cognitively intact first-ever mild-moderate ischemic stroke/transient ischemic attack (TIA) survivors from the Tel Aviv Brain Acute Stroke Cohort (TABASCO) study. They underwent 3T magnetic resonance imaging (MRI) scanning and were cognitively assessed at admission, and at 6, 12 and 24 months post-stroke. Scalp hair samples were obtained during the initial hospitalization. RESULTS: Full data on baseline HCC, MRI scans and 2 years neuropsychological assessments were available for 65 patients. Higher HCC were significantly associated with a larger lesion volume and with worse cognitive results 6, 12 and 24 months post-stroke on most of the neurocognitive tests. 15.4% of the participants went on to develop clinically significant cognitive decline in the follow-up period, and higher HCC at baseline were found to be a significant risk factor for this decline, after adjustment for age, gender, body mass index and APOE e4 carrier status (HR=6.553, p=0.038). CONCLUSIONS: Our findings suggest that individuals with higher HCC, which probably reflect higher long-term cortisol release, are prone to develop cognitive decline following an acute stroke or TIA.

Mechanisms of post-radiation injury: cerebral microinfarction not a significant factor.

Post-radiation leukoencephalopathy is characterized by cognitive impairment and white matter alternations on imaging. Cerebral small vessel disease (SVD) is one of several suggested etiologies. Cerebral microinfarction (CMI) is a recently described marker of SVD. We sought to examine the rate of CMI as a biomarker of ongoing ischemia among patients who underwent brain radiotherapy (RT). 110 patients treated with RT for primary or metastatic brain tumors were enrolled. A total of 685 brain MRI tests performed 1-108 months post-radiation were examined. The annual incidence of CMI was calculated. Only 2 definite CMI were found (2/685, 0.3 %). The calculated annual incidence of CMI was 0.11. This incidence is similar to the normal population, and lower than the reported incidence in patients with intracerebral hemorrhage or cognitive impairment. CMI incidence in patients treated with brain RT is similar to the general population. This finding suggests that post-radiation leukoencephalopathy and cognitive impairment are not due to active SVD solely but rather secondary to other causes such as inflammation, metabolic or direct cell damage.

Symptomatogenic acute cervical artery dissection following dental procedure - Case series.

INTRODUCTION: Cervical artery dissection (CAD) is an important cause of ischemic stroke which may occur following minor traumatic neck manipulations or hyperextension. This paper describes four cases of CAD secondary to dental procedures. CASES: Four patients were admitted to the neurology department due to various neurological deficits, which developed subsequently to dental procedure. CT angiography demonstrated CAD in all patients. No predisposing background disease or other neck manipulations were found. DISCUSSION: We describe four cases of dental procedure induced CAD. Since dental procedures are very common, CAD incidence may be higher than recognized. High clinical suspicion is crucial for promoting vascular imaging and diagnosis, especially among patients with non-neurologically symptomatic CAD. We suggest avoiding prolonged neck hyperextension during dental procedures, especially under general anesthesia, in order to prevent this rare but dramatic complication.

What are the correlates of cognition and participation to return to work after first ever mild stroke?

BACKGROUND: The percentage of working age people with mild stroke has risen. Evidence indicates that even mild stroke impact cognition, executive functioning, and daily functioning, consequently affecting participation, quality of life (QoL) and return to work (RTW). OBJECTIVES: (1) Compare cognition, participation and QoL between people 3 months post-mild stroke who RTW and those who did not; and (2) To determine the correlates of these variables to RTW of participants 3 months post-stroke. METHODS: We visited at home 163 stroke survivors (117 men, 46 women) 3 months post-mild stroke ranging from 50 to 89 years. Participants who returned to work (n = 114) and those who did not (n = 49). Data collection at home included measures for cognitive status (MoCA), executive functions (EFPT, DEX), depression (GDS), participation (RNL), and QoL (SIS recovery). RESULTS: Significant differences were found between RTW participants and those who did not RTW in measures of cognition, depression, participation and QoL (t = 2.36 to - 5.62, P < 0.022-0.001). No difference was found on age or gender. Stepwise regression showed that significant correlates of RTW were participation (RNL), executive functions (EFPT), and QoL (SIS recovery). CONCLUSIONS: To enable RTW after mild stroke, participation, executive functions and QoL must be considered in planning interventions.

Post-stroke cognitive decline: an update and perspectives for clinical research.

The close relationship between stroke and dementia is an important health issue. Ischaemic stroke can facilitate the onset of vascular dementia as well as aggravate pre-existing cognitive decline. The onset of cognitive decline may become manifest immediately following the onset of ischaemic stroke, but often there is a delay in the development of cognitive decline after a stroke. This delay can be seen as a therapeutic time window allowing interventions to be applied to preserve cognition following stroke. Both neurodegenerative and vascular mechanisms are activated and probably result in overlapping processes within the neurovascular unit. This review focuses on the incidence and prevalence of cognitive decline following stroke, predisposing stroke aetiologies, pre-stroke decline, imaging factors and biomarkers. Outcomes are discussed in relation to timing of assessment and neuropsychological tests used for evaluation of cognitive decline in ischaemic stroke patients. Including such tests in routine evaluations of stroke patients after some weeks or months is recommended. Finally, an outlook on ongoing and planned intervention trials is added and some recommendations for future research are proposed.

Stroke service: how can we improve and measure outcomes? Consensus summary from a global stroke forum.

The success of acute stroke treatment is first and foremost time-dependent, and the need for improvement in acute stroke management is demonstrated by the fact that only a minority of patients gain access to treatment - in particular, intravenous recombinant tissue plasminogen activator (IV tPA) - within the necessary time window. Standards of acute stroke care vary widely both regionally and nationally; consequently, various healthcare organizations have undertaken initiatives to measure and improve quality of care. To date, most quality measures have been process-based, focusing primarily on metrics of patient care in the acute hospital-based setting (e.g., time to recombinant tPA administration). Therefore, there remains a need for metrics designed to assess how improvements in process translate into patient outcomes. A global forum was convened to share best practice and provide consensus recommendations on core metrics for measuring improvements in access to care and patient outcomes. Recommendations for core metrics of patient outcomes include hospital-based outcomes (e.g., neurological status at 24 h, ambulatory status at discharge) and post-discharge outcomes (e.g., modified Rankin Scale score at 30 and/or 90 days). Recommendations for best practice relating to aspects of people, process, and technology involved in the stroke treatment pathway that may help provide improvements in these core outcome measures are also outlined.

NeuroThera® Efficacy and Safety Trial-3 (NEST-3): a double-blind, randomized, sham-controlled, parallel group, multicenter, pivotal study to assess the safety and efficacy of transcranial laser therapy with the NeuroThera® Laser System for the treatment of acute ischemic stroke within 24 h of stroke onset.

RATIONALE: Transcranial laser therapy is undergoing clinical trials in patients with acute ischemic stroke. The NeuroThera® Efficacy and Safety Trial-1 was strongly positive for 90-day functional benefit with transcranial laser therapy, and post hoc analyses of the subsequent NeuroThera® Efficacy and Safety Trial-2 trial suggested a meaningful beneficial effect in patients with moderate to moderately severe ischemic stroke within 24 h of onset. These served as the basis for the NeuroThera® Efficacy and Safety Trial-3 randomized controlled trial. AIM: The purpose of this pivotal study was to demonstrate safety and efficacy of transcranial laser therapy with the NeuroThera® Laser System in the treatment of subjects diagnosed with acute ischemic stroke. DESIGN: NeuroThera® Efficacy and Safety Trial-3 is a double-blind, randomized, sham-controlled, parallel group, multicenter, pivotal study that will enroll 1000 subjects at up to 50 sites. All subjects will receive standard medical management based on the American Stroke Association and European Stroke Organization Guidelines. In addition to standard medical management, both groups will undergo the transcranial laser therapy procedure between 4·5 and 24 h of stroke onset. The study population will be randomized into two arms: the sham control group will receive a sham transcranial laser therapy procedure and the transcranial laser therapy group will receive an active transcranial laser therapy procedure. The randomization ratio will be 1:1 and will be stratified to ensure a balanced subject distribution between study arms. STUDY OUTCOMES: The primary efficacy end point is disability at 90 days (or the last rating), as assessed on the modified Rankin Scale, dichotomized as a success (a score of 0-2) or a failure (a score of 3 to 6).

Cognitive assessment in proximity to acute ischemic stroke/transient ischemic attack: comparison of the montreal cognitive assessment test and mindstreams computerized cognitive assessment battery.

BACKGROUND/AIMS: Even mild stroke survivors may sometimes experience residual cognitive damage. No consensus has emerged about which cognitive test is most appropriate for the diagnosis of poststroke cognitive impairment. We aim to compare a computerized battery of neuropsychological tests for memory, attention and executive functions (MindStreams®) with the Montreal Cognitive Assessment (MoCA) to detect mild-to-moderate cognitive impairments in poststroke patients. METHODS: Subjects enrolled to the TABASCO (Tel Aviv Brain Acute Stroke Cohort) study, a prospective study which includes consecutive first-ever mild-to-moderate stroke patients, were included. All participants underwent neurological and cognitive evaluations. RESULTS: A total of 454 patients with transient ischemic attack (TIA) or stroke are reported. Their mean MoCA and MindStreams scores were lower than normal; however, the TIA group presented significantly better scores using either method. The correlation between the MoCA and the computerized global score was 0.6 (p < 0.001). A significant correlation was found between the subcategory scores (executive function, memory and attention). However, the MoCA identified many more subjects with low scores (<26) compared to the MindStreams (70.6 vs. 15.7%). CONCLUSION: Our results demonstrate that either of the modalities alone is sensitive enough for identifying subtle cognitive impairment and none picks up substantially more cognitive losses than the other in patients with cerebrovascular disease.

Clinical consequences of aspirin and clopidogrel resistance: an overview.

The aim of this review is to introduce the concept of personalized medicine in secondary stroke prevention with antiplatelet medication. In the last years, many studies have been conducted regarding aspirin resistance and genotyping of clopidogrel metabolism. A review of the currently published data on this issue emphasizes the importance of focusing on the individualizing approach in antiplatelet therapy to achieve maximal therapeutic beneficial effect. However, many authors suggest that, before new information from ongoing trials become available, good clinical practice should dictate the use of low dose of aspirin that was shown to be effective in the prevention of stroke and death in patients with ischemic cerebrovascular disease, because higher doses do not have significantly better efficacy than lower doses in secondary stroke prevention, but lower-dose aspirin is associated with less side effects. On the other hand, many factors are associated with clopidogrel resistance, and recent genetic studies showed that the CYP2C19*2 genotype (loss-of-function allele) is related to poor metabolism of clopidogrel, but larger studies are needed to definitively confirm or rule out the clinical significance of this genetic effect. The aim of personalized approach in secondary stroke prevention is to take the most appropriate medicine in the right dose in accordance with the clinical condition of the patient and associated risk factors.

Atherosclerosis and arteriosclerosis parameters in stroke patients associate with paraoxonase polymorphism and esterase activities.

BACKGROUND AND PURPOSE: Polymorphic paraoxonase (PON1) variants can variably prevent low- and high-density lipoprotein oxidation, but their role in provoking atherosclerosis remained unclear. We addressed this issue by profiling PON1 polymorphisms and enzymatic activities, and assessing atherosclerosis and cerebral arteriosclerosis severity in post-stroke patients. METHODS: Carotid artery intima-media-thickness (IMT), cerebral white matter lesions (WML), serum PON1 -108C/T, Q192R and L55M polymorphisms, and PON and acetylcholinesterase (AChE) enzyme activities were determined in 237 patients. RESULTS: Genetic variation at the PON1 locus showed a strong influence on PON1 activity in ischaemic stroke patients, but lacked direct influence on IMT. Stroke patients with PON1 QQ192 or MM55 genotypes demonstrated lower PON and arylesterase activities at both Day 1 and 12 months post-stroke than patients with either RQ/RR192 or LM/LL55 genotypes (P < 0.001). Furthermore, patients with carotid atherosclerosis and/or cerebral arteriosclerosis expressed as IMT, carotid plaques and WML had lower 12 months PON1 activity than patients without (P = 0.02, P = 0.027 and P = 0.001, respectively), and PON and AChE hydrolysis rates were more tightly correlated in patients carrying the PON1 192R compared with the 192QQ allele, in a gene dose-dependent manner (P < 0.001). CONCLUSION: Our findings show inverse PON1 activity-carotid atherosclerosis and -cerebral arteriosclerosis association in stroke patients: the lower the PON1 activity the more progressed is the atherosclerotic process and the weaker is the association with AChE activity. Extending previous PON1 genetic studies in stroke populations, our study emphasizes the PON1 activity as a potential anti-atherogenic element and proposes involvement of cholinesterase activities in its effects.

Stroke in the very elderly: characteristics and outcome in patients aged ≥85 years with a first-ever ischemic stroke.

BACKGROUND: Epidemiological and clinical features of very elderly patients with stroke are still uncertain. Our aim was to study the patient characteristics and outcomes in the very elderly (aged ≥85 years) with a first-ever ischemic stroke in the National Acute Stroke Israeli Survey (NASIS) registry. METHODS: The NASIS registry is a nationwide prospective hospital-based study performed triennially (2004, 2007, 2010). Patients with ischemic stroke aged ≥85 years were compared with those 65-84 years old regarding their baseline characteristics, stroke severity, etiology of stroke and stroke outcomes. Logistic regression analyses were used to adjust for potential confounders. Stroke severity was determined according to the National Institute of Health Stroke Scale (NIHSS) score. RESULTS: The proportion of very elderly (≥85 years) patients among the NASIS population increased from 18.3% in 2004 to 19.9% in 2007 and 24.5% in 2010 (p for trend = 0.005). The percentage of women was higher in patients aged ≥85 years (p < 0.0001). Atrial fibrillation, congestive heart disease and prior disability were significantly more common, while diabetes, current smoking and dyslipidemia were less frequent in the very elderly. The very elderly presented with more severe strokes: 36.3% of the ≥85-year-old patients had an NIHSS score ≥11 compared with 22.0% in the younger age group (p < 0.05). CONCLUSIONS: There is an increasing proportion of very elderly subjects, mostly women, among first-ever ischemic stroke patients. Current information on age-specific aspects of stroke in the very elderly is crucial to set up successful prevention pathways and implementing well-organized stroke care for this population.

Vasomotor reactivity as a predictor for syncope in patients with orthostatism.

OBJECTIVES: Syncope in patients with orthostatic hypotension (OH) may be the result of impaired cerebral autoregulation. Cerebral autoregulation status can be determined by assessing cerebral vasomotor reactivity (VMR). We assessed and compared VMR in patients with OH with and without syncope. MATERIAL AND METHODS: Twenty-nine patients with OH underwent transcranial Doppler (TCD) and the Diamox test (1 g acetazolamide IV) for assessing VMR during elaboration of their OH syndrome. The percent difference between cerebral blood flow velocities (BFV) in the middle cerebral (MCA) and vertebral (VA) arteries before and after acetazolamide was defined as VMR%. We considered increases of BFV of ≥ 40% as being indicative of good VMR and classified our study patients as having good or impaired VMRs accordingly. RESULTS: Mean VMR% values of the MCA and VA in patients with OH with syncope (n = 12) were significantly lower as compared with patients with OH without syncope (n = 17): 25.2 ± 20.5% and 42.5 ± 18.6%; 20.9 ± 15.5% and 40.8 ± 28.5%, respectively (P < 0.05). CONCLUSIONS: Among patients with OH, we found an association between the presence of syncope and impaired VMR. Assessment of VMR among patients with OH may predict those who are at higher risk to faint and fall and to support more aggressive intervention.

Extra-cranial venous flow in patients with multiple sclerosis.

INTRODUCTION: Recently, a chronic state of impaired venous drainage from the central nervous system, termed chronic cerebrospinal venous insufficiency (CCSVI) was claimed to be a pathologic condition exclusively seen in patients with multiple sclerosis (MS), suggesting that cerebral venous congestion plays a significant role in the pathogenesis of MS. This hypothesis has gained enormous attention among patients and physicians but has been questioned since. METHODS: Twenty seven patients with MS and 32 healthy controls underwent color extra cranial Doppler exam aimed to detect four parameters of abnormal venous flow: no Doppler-detected flow in the IJV or vertebral veins (VV), reflux in the internal jugular veins (IJVs), venous flow stenosis in the IJVz (cross sectional area <0.3 cm) or reverted postural control in the IJV. RESULTS: Except for one healthy patient, blood flow direction in the IJVs was normal in all subjects. When aiming to detect at least one parameter of abnormal venous flow per subject, two parameters or three parameters no significant difference was found between subjects and controls (p = 0.707, 0.62, 0.849 respectively). CONCLUSION: We found no evidence to suggest that MS patients have excess of CCSVI. In addition we failed to observe a typical venous flow pattern in MS patients. Until carefully designed controlled studies to investigate CCVSI have been completed, invasive and potentially dangerous endovascular procedures as therapy for MS should be discouraged.

Characteristics of first ever ischemic stroke in the very elderly: profile of vascular risk factors and clinical outcome.

PURPOSE: Age is the most significant non-modifiable risk factor for ischemic stroke (IS). With increasing expectancy of life, the majority of IS patients will be elderly subjects. We studied the epidemiological, clinical and rehabilitation features of patients aged ≥85 years with first-ever IS. METHODS: Demographic data, prevalence of risk factors, etiology of stroke, severity of neurological deficit, major complications and mortality rates were collected from a hospital-based stroke registry and compared between patients at the age of 65-84 and ≥85. Clinical assessment was performed by means of the National Institutes of Health Stroke Scale (NIHSS) and Modified Rankin Scale (mRS). RESULTS: Among 216 patients aged ≥85 years there was significantly higher proportion of a history of atrial fibrillation than in 128 patients at the age of 65-84 years and lower prevalence of hypertension, diabetes mellitus, hyperlipidemia and smoking. Large artery atherosclerosis was more frequently identified in the older patients (49% vs. 32%, p=0.002). Although NIHSS scores on admission were lower in the older patients they were more disabled at discharge. CONCLUSIONS: With respect to the patients aged <85 years very old IS patients showed different vascular risk factors profile, clinical and rehabilitation course. These findings suggest specializing stroke care in the very elderly.

Ethnic variations in acute ischemic stroke: findings from the National Acute Stroke Israeli Survey (NASIS).

BACKGROUND: We intended to determine ethnic differences in the characteristics, management and outcome of acute ischemic stroke between the Israeli Arab and Jewish populations. METHODS: A national survey was conducted in 2004 at all 28 hospitals in Israel. Information on demographics, transportation, risk factors, clinical presentation, stroke severity, type and subtype, management and clinical outcome was obtained. Mortality during the 36 months after hospitalization was assessed by matching with national mortality data. RESULTS: Of the 1,540 patients, 169 (11%) were Arabs and 1,371 (89%) were Jews. The mean age of Arab patients was 9 years younger than in Jewish patients (63 ± 11 vs. 72 ± 12 years). Also, Arabs were more likely to be obese (OR = 1.72; 95% CI: 1.19-2.50) and have diabetes (OR = 1.41; 95% CI: 1.01-1.96), while Jews were more likely to have dyslipidemia (OR = 1.56; 95% CI: 1.11-2.17). A greater percentage of the Arab patients arrived at the hospital independently (OR = 3.85; 95% CI: 2.56-5.56) and were less likely to arrive within 3 h of symptom onset (OR = 2.33; 95% CI: 1.39-3.85). Arabs suffered increased rates of lacunar stroke (OR = 1.67; 95% CI: 1.14-2.43) and were discharged home more often (OR = 2.40; 95% CI: 1.35-4.25). No differences in severity of stroke, management, complications, disability or mortality were found between the 2 groups. CONCLUSIONS: The unique characteristics of the Arab and Jewish populations should be considered when planning stroke-care services and culturally oriented public education programs.

Clinical, radiological and pathological correlates of leukoaraiosis.

INTRODUCTION: Leukoaraiosis is characterized by an abnormal appearance of the brain white matter on imaging. Its pathogenesis is still a matter of investigation. The purpose of this study was to investigate the radiological, clinical and pathological correlates of leukoaraiosis. METHODS: The study population consisted of 93 deceased patients. The pre-mortem T2W magnetic resonance images were evaluated for the presence and grading of leukoaraiosis. The clinical and pathological characteristics based on the clinical charts and autopsy reports were evaluated. Tissue specimens of the blocks of 19 brains that demonstrated severe leukoaraiosis and those of five control brains were excised and stained. RESULTS: The variables found to be significantly associated with leukoaraiosis were age and a clinical history of Parkinson's disease. Other risk factors and pathological markers of atherosclerosis were not significantly correlated with leukoaraiosis. No significant difference was found between the scoring of the myelin integrity, glial fibrillary acidic protein, cluster of differentiation 68 and smooth muscle actin. There was a significant difference with respect to thickening of vessels walls. CONCLUSIONS: Our pathological results indicate that structural vascular abnormalities characterized by vessel wall thickening are associated with leukoaraiosis, supporting the assertion that vascular changes and ischemia generate leukoaraiosis. The relations between parkinsonism and leukoaraiosis may be explicable through vascular effects on the circuitry of the basal ganglia.

Neuroprotection in acute ischemic stroke--current status.

With the growing understanding of the mechanism of cell death in ischemia, new approaches for treatment such as neuroprotection have emerged. The basic aim of this strategy is to interfere with the events of the ischemic cascade, blocking the pathological processes and preventing the death of nerve cells in the ischemic penumebra. This concept involves inhibition of the pathological molecular events which eventually leads to the influx of calcium, activation of free radicals and neuronal death. Despite encouraging data from experimental animal models, all clinical trials of neuroprotective therapies have to date been unsuccessful. This article reviews some of the reasons for the failure of neuroprotection in the clinical trials so far. Despite all the negative reports, we believe it would be wrong to give up at this point, since there is still reasonable hope of finding an effective neuroprotection for stroke.