Osteoprotegerin Assessment Improves Prediction of Mortality in Stroke Patients.

BACKGROUND: Elevated circulating osteoprotegerin (OPG) level is associated with an increased risk of hospitalization for ischemic stroke and coronary artery disease. The aim of the present study was to analyze whether OPG assessment may improve the prediction of mortality in patients with stroke. PATIENTS AND METHODS: Serum OPG, fetuin A, 25-OH-D3, intact parathyroid hormone levels were assessed in serum samples which were left over after routine tests in a hospital laboratory. This assessment was conducted in 240 consecutive patients with acute ischemic stroke, admitted within 24hours after the onset of symptoms to the Stroke Unit. Mortality data were obtained from the local registry office. RESULTS: The mean OPG serum level was 14.6 ± 6.0pmol/L (range: 3.7-43.4). There were no significant differences in the OPG values between men and women (13.9 ± 5.0 versus 15.1 ± 6.7 pmol/L; P = .12). Therefore, tertiles were calculated for the whole group. During the follow-up, 85 (35.4%) patients died and 92 (38.3%) died or had recurrent stroke. OPG level appeared a significant predictors of death and composite end-point (death/recurrent stroke), in addition to the well-established once (age, atrial fibrillation, diabetes RANKIN at admission and discharge, severity of stroke). In multivariable stepwise backward analyses, the OPG level persisted as a significant and independent predictor of death (hazard ratio [HR] = 1.084 (95% confidence intervals: 1.036-1.134)] and composite and point (HR = 1.082 [1.037-1.129]). CONCLUSIONS: OPG level may be considered as a predictor of mortality in stroke patients.

Altered Fibrin Clot Properties in Patients With Cerebral Venous Sinus Thrombosis: Association With the Risk of Recurrence.

BACKGROUND AND PURPOSE: Venous thromboembolism and ischemic stroke are associated with unfavorable fibrin clot structure and function. We hypothesized that denser fibrin networks displaying impaired lysability characterize patients with cerebral venous sinus thrombosis (CVST). METHODS: We assessed plasma fibrin clot properties in 50 patients (aged 38.9±9.8 years, 36 women) after the first CVST unrelated to trauma or malignancy after anticoagulation withdrawal and 50 well-matched controls. Recurrences were recorded during follow-up (18-46; median, 36 months). RESULTS: Clot permeability was lower in patients with CVST than in controls (Ks, 6.43±0.97 versus 7.3±1.2 10(-9) cm(2); P<0.001) and was associated with prolonged clot lysis time (103.0±16.8 versus 92.4±16.2 minutes; P<0.001), lower maximum rate of D-dimer release from clots (0.068 [0.064-0.071] versus 0.072 [0.067-0.078] mg/L per minute; P<0.001) and higher maximum D-dimer levels in the lysis assay (4.39±0.56 versus 4.19±0.46 mg/L, respectively; P=0.03). Patients with CVST had a slightly shorter lag phase (P=0.02) and higher maximum absorbance of fibrin gels on turbidimetry (P<0.001) compared with controls. Deficiencies in natural anticoagulants or antiphospholipid syndrome, and factor V Leiden occurred more often in the patients (P<0.05). CVST recurred in 6 patients (12%) and was associated with 21% higher baseline fibrinogen (P=0.007), 20% lower Ks (P=0.04) and 17% greater D-Dmax (P=0.01). Multiple logistic regression showed that only elevated D-Dmax (>4.83 mg/L) predicted CVST recurrence (odds ratio, 5.1; 95% confidence interval, 1.63-16.19) after adjustment for fibrinogen. CONCLUSIONS: CVST is associated with the formation of more compact plasma fibrin clots and resistance to fibrinolysis, which may predispose to the recurrence.

Molecular mechanisms of microRNAs in glioblastoma pathogenesis.

Glioblastoma (GBM) is human's most prevalent and severe brain cancer. Epigenetic regulators, micro(mi)RNAs, significantly impact cellular health and disease because of their wide range of targets and functions. The "epigenetic symphony" in which miRNAs perform is responsible for orchestrating the transcription of genetic information. The discovery of regulatory miRNA activities in GBM biology has shown that various miRNAs play a vital role in disease onset and development. Here, we summarize our current understanding of the current state-of-the-art and latest findings regarding the interactions between miRNAs and molecular mechanisms commonly associated with GBM pathogenesis. Moreover, by literature review and reconstruction of the GBM gene regulatory network, we uncovered the connection between miRNAs and critical signaling pathways such as cell proliferation, invasion, and cell death, which provides promising hints for identifying potential therapeutic targets for the treatment of GBM. In addition, the role of miRNAs in GBM patient survival was investigated. The present review, which contains new analyses of the previous literature, may lead to new avenues to explore in the future for the development of multitargeted miRNA-based therapies for GBM.

Integrating Multi-Omics Analysis for Enhanced Diagnosis and Treatment of Glioblastoma: A Comprehensive Data-Driven Approach.

The most aggressive primary malignant brain tumor in adults is glioblastoma (GBM), which has poor overall survival (OS). There is a high relapse rate among patients with GBM despite maximally safe surgery, radiation therapy, temozolomide (TMZ), and aggressive treatment. Hence, there is an urgent and unmet clinical need for new approaches to managing GBM. The current study identified modules (MYC, EGFR, PIK3CA, SUZ12, and SPRK2) involved in GBM disease through the NeDRex plugin. Furthermore, hub genes were identified in a comprehensive interaction network containing 7560 proteins related to GBM disease and 3860 proteins associated with signaling pathways involved in GBM. By integrating the results of the analyses mentioned above and again performing centrality analysis, eleven key genes involved in GBM disease were identified. ProteomicsDB and Gliovis databases were used for determining the gene expression in normal and tumor brain tissue. The NetworkAnalyst and the mGWAS-Explorer tools identified miRNAs, SNPs, and metabolites associated with these 11 genes. Moreover, a literature review of recent studies revealed other lists of metabolites related to GBM disease. The enrichment analysis of identified genes, miRNAs, and metabolites associated with GBM disease was performed using ExpressAnalyst, miEAA, and MetaboAnalyst tools. Further investigation of metabolite roles in GBM was performed using pathway, joint pathway, and network analyses. The results of this study allowed us to identify 11 genes (UBC, HDAC1, CTNNB1, TRIM28, CSNK2A1, RBBP4, TP53, APP, DAB1, PINK1, and RELN), five miRNAs (hsa-mir-221-3p, hsa-mir-30a-5p, hsa-mir-15a-5p, hsa-mir-130a-3p, and hsa-let-7b-5p), six metabolites (HDL, N6-acetyl-L-lysine, cholesterol, formate, N, N-dimethylglycine/xylose, and X2. piperidinone) and 15 distinct signaling pathways that play an indispensable role in GBM disease development. The identified top genes, miRNAs, and metabolite signatures can be targeted to establish early diagnostic methods and plan personalized GBM treatment strategies.

Percutaneous closure of the left atrial appendage to prevent ischaemic stroke in patients with atrial fibrillation who require but have contraindications to oral anticoagulation.

Atrial fibrillation (AF) is associated with a five-fold increased risk for stroke due to cardioembolic events. Most strokes in patients with AF arise from thrombus formation in the left atrial appendage (LAA). Oral anticoagulation is a standard treatment of AF patients with high risk of stroke. However, the main drawbacks of oral anticoagulation are high risk of major bleeding and imperfect effectiveness dependent on a very narrow therapeutic range. In this article, based on two case reports, we describe a method of percutaneous closure of the LAA. We discuss indications, describe the procedure and mention possible complications. LAA closure seems to be a promising tool to prevent AF-related strokes in a selected group of patients.

An endovascular treatment of Chronic Cerebro-Spinal Venous Insufficiency in multiple sclerosis patients - 6 month follow-up results.

OBJECTIVE: In this study, the mid-term results (6 month follow-up) of the endovascular treatment in patients with Chronic Cerebro-Spinal Venous Insufficiency (CCSVI) and multiple sclerosis (MS) were prospectively evaluated. METHODS: Thirty-six patients with confirmed MS and CCSVI underwent endovascular treatment by the means of the uni- or bilateral jugular vein angioplasty with optional stent placement. All the patients completed 6 month follow-up. Their MS-related disability status and quality of life were evaluated 1, 3 and 6 months postoperatively by means of the following scales: Expanded Disability Status Scale (EDSS), Multiple Sclerosis Impact Scale (MSIS-29), Epworth Sleepiness Scale (ESS), Heat Intolerance scale (HIS) and Fatigue Severity Scale (FSS). For patency and restenosis rate assessment, the control US duplex Doppler examination was used. RESULTS: Six months after the procedure, restenosis in post-PTA jugular veins was found in 33% of cases. Among 17 patients who underwent stent implantation into the jugular vein, restenosis or partial in-stent thrombosis was identified in 55% of the cases. At the 6 month follow-up appointment, there was no significant improvement in the EDSS or the ESS. The endovascular treatment of the CCSVI improved the quality of life according to the MSIS-29 scale but only up to 3 months after the procedure (with no differences in the 6 month follow-up assessment). Six months after the jugular vein angioplasty (with or without stent placement), a statistically significant improvement was observed only in the FSS and the HIS. CONCLUSIONS: The endovascular treatment in patients with MS and concomitant CCSVI did not have an influence on the patient's neurological condition; however, in the mid-term follow-up, an improvement in some quality-of-life parameters was observed.

Decompressive hemicraniectomy in ischaemic stroke.

BACKGROUND AND PURPOSE: Hemispheric ischaemic stroke complicated by oedema is associated with high mortality. The results of randomized studies showed that decompressive hemicraniectomy performed in this group of patients could be beneficial. First experiences with implementation of hemi-craniectomy in patients with brain infarct in our stroke centre are presented. MATERIAL AND METHODS: Between August 2007 and July 2008, four patients with hemispheric brain infarcts complicated by malignant oedema underwent decompressive hemicraniectomy within 72 hours from symptoms onset. Stroke severity was assessed with the National Institutes of Health Stroke Scale (NIHSS). Clinical outcome was assessed 3, 6 and 12 months after the event using the modified Rankin scale (mRS). RESULTS: In the first patient, the neurosurgical procedure included only decompressive hemicraniectomy, whereas in the other three duraplasty was performed additionally. The first patient died 23 days after the stroke onset due to acute respiratory failure. Another died at four months after the event, due to infectious complications. The remaining two patients presented severe functional disability 12 months after the procedure (mRS score 4). CONCLUSIONS: Decompressive surgery with duraplasty can be a life-saving procedure for patients with brain oedema. To our knowledge, the presented cases are among the first reported cases of hemispheric ischaemic stroke treated with decompressive hemicraniectomy in Poland. Extended follow-up with a larger group of patients is necessary to assess long-term outcome.

Adequate Knowledge of Stroke Symptoms, Risk Factors, and Necessary Actions in the General Population of Southern Poland.

BACKGROUND AND OBJECTIVES: Stroke is the third most common cause of mortality in developed countries and the primary cause of neurological disability in adults. Recombinant tissue plasminogen activator administered intravenously within 4.5 h from the onset of symptoms constitutes a gold standard in the treatment of acute ischemic stroke. Prompt hospital admission is the prerequisite of effective thrombolysis. Therefore, stroke awareness in the general population is the key factor in timely recognition of the acute stroke victims and determines proper actions. Therefore, the purpose of this study was to determine the awareness of stroke in the general population of the Silesian voivodeship, the most populated region of Poland. We assessed also the "adequate knowledge of stroke", a combined measure of the optimal level of stroke awareness, as a prerequisite for effective stroke management, and aimed to identify most impacting factor for adequate stoke knowledge, to help shaping education strategies. MATERIALS AND METHODS: A proprietary anonymous questionnaire consisting of 15 items related to stroke was used in this research. A total of 1134 individuals were surveyed. Additionally to the knowledge of individual aspects of stroke, we assessed "adequate knowledge of stroke", which was combined measure of risk factors, symptoms, and actions in the case of acute stroke. RESULTS: The accurate definition of stroke was selected by 834 participants (73.5%). The vast majority of them indicated that a stroke is an emergency (92.8%) and medical assistance is required (97.5%). However, 42.4% of respondents did not know any specific symptom of stroke and only 38.6% participants were able to list two or more risk factors, which resulted in only 36.3% of individuals with adequate knowledge of stroke. Education duration, previous occurrence of stroke in relatives or friends, gender and place of residence were identified as independent predictors of adequate knowledge of stroke. CONCLUSIONS: 1. Knowledge of stroke in the population of southern Poland is low and may be considered insufficient to address the needs of timely management in the action chain. 2. Previous occurrence of stroke in the relatives or friends is the most impacting factor for adequate knowledge of stroke.

Higher Serum-Soluble α-Klotho Level Does Not Predict Longer Survival after Stroke.

RESULTS: There were 5 recurrent strokes and 89 deaths during the 36-month follow-up. Even though no significant differences in OS and SFS between soluble α-Klotho level tertile groups were recorded, unexpectedly, OS and SFS were highest in patients with the lowest soluble α-Klotho concentrations. Moreover, the Cox proportional models adjusted for established risk factors, kidney function, and the severity of stroke revealed that each 100 pg/mL increase in soluble α-Klotho levels was associated with decreased OS (HR = 0.951 (0.908-0.995), p < 0.05) and SFS (HR = 0.949 (0.908-0.993), p < 0.05). In addition, the α-Klotho to iFGF23 index was predicting neither OS nor SFS. CONCLUSION: Soluble α-Klotho levels in serum were not related to the severity of neurological deficits and long-term outcomes in patients with IS. No neuroprotective effect of soluble α-Klotho levels in patients with IS was demonstrated.

Middle cerebral artery vasospasm: transcranial color-coded duplex sonography versus conventional nonimaging transcranial Doppler sonography.

OBJECTIVE: To prospectively compare accuracies of transcranial color-coded duplex sonography (TCCS) and transcranial Doppler sonography (TCD) in the diagnosis of middle cerebral artery (MCA) vasospasm. DESIGN: Prospective blinded head-to-head comparison TCD and TCCS methods using digital subtraction angiography (DSA) as the reference standard. SETTING: Department of Radiology in a tertiary university health center in a metropolitan area. PATIENTS: Eighty-one consecutive patients (mean age, 53.9 +/- 13.9 years; 48 women). The indication for DSA was subarachnoid hemorrhage in 71 patients (87.6%), stroke or transient ischemic attack in five patients (6.2%), and other reasons in five patients (6.2%). INTERVENTIONS: The MCA was graded as normal, narrowed <50%, and >50% using DSA. The accuracy of ultrasound methods was estimated by total area (Az) under receiver operator characteristic curve. To compare sensitivities of ultrasound methods, McNemar's test was used with mean velocity thresholds of 120 cm/sec for the detection of less advanced, and 200 cm/sec for the more advanced MCA narrowing. MEASUREMENTS AND MAIN RESULTS: Angiographic MCA narrowing 50% in 10 of 135 arteries. Accuracy of TCCS was insignificantly higher than that of TCD in the detection of 50% narrowing, total Az for mean velocity being 0.83 +/- 0.05, 0.77 +/- 0.05, and 0.95 +/- 0.02, 0.86 +/- 0.08, respectively. Sensitivity of TCCS at commonly used threshold of 120 cm/sec for less advanced MCA spasm was significantly better than that of TCD at similar specificity, 55% vs. 39%, p = 0.038, whereas at a threshold of 200 cm/sec used for more advanced spasm, sensitivities and specificities of both methods were not different. CONCLUSION: The accuracy of TCCS and TCD is similar, but TCCS is more sensitive than TCD in the detection of MCA spasm. Sensitivity of both techniques in the detection of mild and more advanced spasm using 120 cm/sec and 200 cm/sec thresholds, respectively, is poor; however, a larger sample is required to increase precision of our sensitivity estimates.

Perfusion computed tomography in prediction of functional outcome in patients with acute ischaemic stroke.

PURPOSE: To determine the value of perfusion computed tomography (CT) in prediction of the clinical course and late functional outcome in patients with acute ischaemic stroke who had unremarkable initial brain CT examination. MATERIAL AND METHODS: Single slice perfusion CT was performed in 55 consecutive patients (27 women, mean age 67 +/- 11 years) with acute ischaemic stroke within 6 hours (median 2.26 hours) from onset of symptoms. Values of cerebral blood flow (CBF), cerebral blood volume (CBV), and mean transit time (MTT) obtained from affected hemisphere were compared to respective values in non-affected hemisphere (relative parameters). Initial neurological deficits were estimated using NIH Stroke Scale (NIHSS) score and correlated with perfusion CT values, employing Spearman rank correlation coefficient (r). Values of perfusion CT parameters in prediction of functional outcome were determined by comparing against scores on modified Rankin Scale (mRS) and Glasgow Outcome Scale (GOS) after three months of onset of stroke. RESULTS: All perfusion CT parameters significantly correlated with initial neurological deficit. The highest correlation with the NIHSS was found for relative CBF, which correlated better than absolute CBF (rCBF r = 0.69; CBF r = 0.50, P < 0.001). In prediction of favourable outcome (mRS

Severity of Vitamin D Deficiency Predicts Mortality in Ischemic Stroke Patients.

BACKGROUND: Vitamin D (VD) deficiency is considered an independent risk factor for death due to cardiovascular events including ischemic stroke (IS). We assessed the hypothesis that decreased levels of 25-hydroxyvitamin D (25-OH-D) are associated with increased risk of mortality in patients with IS. METHODS: Serum 25-OH-D, intact parathyroid hormone (iPTH), and intact fibroblast growth factor 23 (iFGF23) levels were assessed in serum of 240 consecutive patients admitted within the 24 hours after the onset of IS. Mortality data was obtained from the local registry office. RESULTS: Only three subjects (1.3%) had an optimal 25-OH-D level (30-80 ng/mL), 25 (10.4%) had a mildly reduced (insufficient) level, 61 (25.4%) had moderate deficiency, and 151 (62.9%) had a severe VD deficiency. 20% subjects had secondary hyperparathyroidism. The serum 25-OH-D level was significantly lower than that in 480 matched subjects (9.9 ± 7.1 vs. 21.0 ± 8.7 ng/mL). Of all the patients, 79 (32.9%) died during follow-up observation (44.9 months). The mortality rates (per year) were 4.81 and 1.89 in a group with and without severe VD deficiency, respectively (incidence rate ratio: 2.52; 95% CI: 1.44-4.68). There was no effect of secondary hyperparathyroidism and iFGF23 levels on mortality rates. Age, 25 - OH - D < 10 ng/mL, and functional status (modified Rankin scale) were significant factors increasing the risk of death in multivariable Cox proportional hazard regression test. CONCLUSIONS: Severe VD deficiency is an emerging, strong negative predictor for survival after IS, independent of age and functional status. VD supplementation in IS survivals may be considered due to high prevalence of its deficiency. However, it is uncertain whether it will improve their survival.

Suitability of temporal bone acoustic window: conventional TCD versus transcranial color-coded duplex sonography.

PURPOSE AND BACKGROUND: To determine whether the proportion of patients with suitable temporal bone acoustic windows is different for conventional transcranial Doppler sonography (TCD) and transcranial color-coded duplex sonography (TCCS), based on a head-to-head comparison in the same population of patients. SUBJECTS AND METHODS: Ninety patients, age 22-88 years (mean 57.1 +/- 11.7 years), 46 women and 44 men, 66 Caucasian, 19 African-American, and five Hispanic, underwent routine conventional TCD and the TCCS examination close in time to each other. Suitability of temporal bone acoustic window was defined by ability to insonate the middle and posterior and/or anterior cerebral arteries, while partial suitability was defined by ability to detect the posterior cerebral artery but not the middle cerebral artery. To compare proportions of suitable temporal bone windows for both sonographic methods, exact sign test by Liddell was used. RESULTS: Bilateral absence of temporal bone acoustic window was reported in six patients when studied with both conventional TCD and TCCS, whereas at least unilateral absence was reported in 10 patients. Partial, at least unilateral, suitability was reported in 11 patients with conventional TCD, and in 7 with TCCS. All differences in proportions were not significant (two-sided P>0.05). CONCLUSIONS: This study suggests that success rate of insonating the intracranial vessels through the temporal bone acoustic window is the same for conventional TCD and imaging TCCS.

Cerebral hemodynamics and investigations of cerebral blood flow regulation.

To maintain adequate cerebral blood flow despite frequent changes in systemic arterial blood pressure and to constantly adjust blood supply to the current metabolic demand dictated by neuronal electrical activity, brain developed a myriad of mechanisms. These are designed to protect central nervous system from fatal consequences of hypoxia and energy deficit and are collectively called "cerebral autoregulation". Despite years of research mechanisms responsible for regulation of CBF functioning under physiologic and pathologic conditions are still not clear. When these mechanisms are damaged or exhausted, patients life is in danger, as even slight, negligible under normal conditions, systemic hemodynamic disturbances might lead to cerebral infarct. Even perfect imaging of the irreversible brain damage with MR for the particular patient is too late action. Thus, detection of cerebral blood flow disturbances and impaired autoregulation, which are known to be associated with high risk of stroke, are extremely important in clinical practice. Several methods have been developed to quantify this process and thus evaluate risk of cerebral ischemia and guide therapeutic process. This review focuses on current knowledge on physiology of regulation of cerebral blood flow, mechanisms responsible for brain damage resulted from cerebral ischemia and reviews noninvasive diagnostic tests to assess cerebral autoregulation.

[Functional imaging in movement disorders]. / Obrazowanie czynnosciowe w diagnostyce schorzen ukladu pozapiramidowego.

Parkinsonian syndromes in the early stage are often misdiagnosed in the general practice. Neuroimaging brings information about changes in the anatomical structure of the brain, which are not typical of movement disorders. The introduction of a functional imaging with the use of presynaptic tracers of the dopaminergic system enables proving nigrostriatal degeneration and supporting the clinical diagnosis of Parkinsonism even in the early phase of the disease. Availability of the single photon emission computer tomography (SPECT) imaging in the nuclear medicine departments gives an opportunity to introduce this neuroimaging method in Poland. In this review we present methods of functional imaging of the brain, particularly of the dopaminergic pathway with the use of SPECT tracers. The role of functional imaging in movement disorders workup for the neurologist is discussed.

Acute intracranial in-stent thrombosis after angioplasty of middle cerebral artery symptomatic stenosis: a case report.

INTRODUCTION: Intracranial atherosclerotic disease is one of the major risk factors of ischemic stroke. Percutaneous transluminal angioplasty with stent deployment may be effective for the treatment of symptomatic intracranial stenosis, however its value is yet to be determined. High possibility of serious periprocedural complications, such as acute in-stent thrombosis or stroke, narrows the current recommendations for this treatment to patients with high-grade stenosis (>70%), and to experienced neurointerventional centers. CASE REPORT: We present a 44-year-old male with symptomatic high-grade stenosis of the M1 segment of left middle cerebral artery, treated with percutaneous transluminal angioplasty with stenting. The procedure was complicated with acute in-stent thrombosis treated with intra-arterial thrombolysis, which resulted in a nondisabling stroke. CONCLUSIONS: The procedure-related stroke in this patient was probably caused by middle cerebral artery perforator ostium occlusion with balloon predilatation and transient in-stent thrombosis related to insufficient antiplatelet pretreatment. Exhausted cerebrovascular reserve due to long-lasting high-grade intracranial stenosis should also be considered as a factor contributing to ischemic complications.

Narrowing of the middle cerebral artery: artificial intelligence methods and comparison of transcranial color coded duplex sonography with conventional TCD.

The goal of the study was to compare performances of transcranial color-coded duplex sonography (TCCS) and transcranial Doppler sonography (TCD) in the diagnosis of the middle cerebral artery (MCA) narrowing in the same population of patients using statistical and nonstatistical intelligent models for data analysis. We prospectively collected data from 179 consecutive routine digital subtraction angiography (DSA) procedures performed in 111 patients (mean age 54.17+/-14.4 years; 59 women, 52 men) who underwent TCD and TCCS examinations simultaneously. Each patient was examined independently using both ultrasound techniques, 267 M1 segments of MCA were assessed and narrowings were classified as < or =50% and >50% lumen reduction. Diagnostic performance was estimated by two statistical and two artificial neural networks (ANN) classification methods. Separate models were constructed for the TCD and TCCS sonographic data, as well as for detection of "any narrowing" and "severe narrowing" of the MCA. Input for each classifier consisted of the peak-systolic, mean and end-diastolic velocities measured with each sonographic method; the output was MCA narrowing. Arterial narrowings less or equal 50% of lumen reduction were found in 55 and >50% narrowings in 26 out of 267 arteries, as indicated by DSA. In the category of "any narrowing" the rate of correct assignment by all models was 82% to 83% for TCCS and 79% to 81% for TCD. In the diagnosis of >50% narrowing the overall classification accuracy remained in the range of 89% to 90% for TCCS data and 90% to 91% for TCD data. For the diagnosis of any narrowing, the sensitivity of the TCCS was significantly higher than that of the TCD, while for diagnosis of >50% MCA narrowing, sensitivity of the TCCS was similar to sensitivity of the TCD. Our study showed that TCCS outperforms conventional TCD in detection of < or =50% MCA narrowing, whereas no significant difference in accuracy between both methods was found in the diagnosis of >50% MCA narrowing. (E-mail: jaroslaw.krejza@uphs.upenn.edu).