Stroke burden in Egypt: data from five epidemiological studies.

PURPOSE: Accurate data on the epidemiology of stroke in Egypt is scarce. The aim of this review is to address this issue based on available community-based studies and compare the resulting findings to those of other regional and international studies. METHOD: A systematic literature search was conducted to identify population-based epidemiological studies of stroke in Egyptians. Original articles published in English between 1990 and 2016 were included. Five studies from five different governorates in southern Egypt fulfilled the study criteria (Qena, Sohag, Assiut, New Valley and Red Sea). RESULTS: The mean and median crude prevalence rates (CPRs) across the five studies, which were conducted in southern Egypt were 721.6/100,000 and 655/100,000, respectively. The mean and median crude incidence rates (CIRs) were 187/100,000 and 180.5/100,000, respectively. The average CPR weighted by sample population size was 613/100,000 and the average CIR weighted by sample population size was 202/100,000. CONCLUSION: The incidence and prevalence of stroke in Egypt are high. More population-based studies are urgently needed in northern Egypt and in Cairo - the capital of Egypt.

Sonothrombolysis in acute middle cerebral artery stroke.

OBJECTIVES: The objective of the following study is to determine the effect of continuous insonation using 2-MHz transcranial Doppler-ultrasound (TCD-US) on the recanalization rate and the short-term outcome in subjects with acute ischemic stroke due to middle cerebral artery (MCA) occlusion. MATERIALS AND METHODS: A total of 42 patients with acute ischemic stroke due to MCA occlusion within 24 h were recruited and randomly allotted to two groups (21 patients in each group). Group 1 included patients who received 1 h continuous TCD-US for MCA and Group 2 included patients who did not receive 1 h continuous TCD-US. Patients in both groups were received MCA insonation and TCD study to measure mean flow velocity (MFV) in MCA one after the initial study at 20 and 60 min. All patients received aspirin (150-325 mg). The clinical course during hospital stay was assessed before and after 1 h of US insonation, at 24 h after symptom onset using the National Institutes of Health Stroke Scale. RESULTS: Change in MFV after insonation for Group 1 in comparison to Group 2 at 3 time points was significantly high (P < 0.001). CONCLUSION: Sonothrombolysis is a therapeutic option to improve the outcomes in patients with acute ischemic stroke due to MCA occlusion.

Intracranial steno-occlusive arterial disease and its associations in Egyptian ischemic stroke patients.

BACKGROUND AND PURPOSE: Intracranial arterial steno-occlusive disease is prevalent among non-white populations. We explored whether a similar pattern exists in Egyptians and assessed its clinical-radiological associations. METHODS: Consecutive acute ischemic stroke patients were recruited for 6 months and had magnetic resonance imaging/magnetic resonance angiography of brain within 2 days of the event. Magnetic resonance angiography was analyzed for significant stenosis (>50%), flow gaps, and complete occlusions in the major intracranial arteries. RESULTS: A total of 143 patients completed the study (62.4 ± 12.6 years, 58.7% males). Magnetic resonance angiography showed symptomatic arterial stenosis in 27.3%, asymptomatic stenosis in 16.1%, and occlusions in 23.7% patients. Carotid duplex showed stenosis >70% in only 7.7% patients. Patients with intracranial arterial steno-occlusive disease had higher National Institutes of Health Stroke Score at admission (10.9 ± 7 versus 8 ± 5.6; P=0.01). CONCLUSIONS: Symptomatic and asymptomatic intracranial arterial steno-occlusive disease was prevalent in this Egyptian acute stroke sample. This might have important implications on stroke management in this population.

Association of white matter hyperintensities with migraine phenotypes and response to treatment.

INTRODUCTION: White matter hyperintensities (WMHs) are frequently found in migraineurs. However, their clinical significance and correlation to different migraine phenotypes and treatment responses are not well defined. The study aimed to examine the association of WMHs with migraine clinical patterns and treatment response. AIM OF WORK: We aimed to evaluate the association between WMHs and migraine phenotypes and explore the relationship of WMHs to treatment response. METHODS: Our cross-sectional study formed of 500 migraineurs who sought treatment in Kafr el-sheik university hospital and underwent (3 T) MRI to evaluate WMHs. Different migraine phenotypes were compared between patients with and without WMHs. According to reduced headache pain intensity and frequency, these patients were divided into treatment responder and non-responder groups. RESULTS: A total of 145 patients (29%) had WMHs. Patients with WMHs were significantly older, had a longer disease duration, and higher attack frequency. Patients who did not respond to acute and maintenance medications had a higher frequency of WMHs and high WMHs Scheltens score. Migraine with Aura and the presence of vomiting and dizziness were predictors for the development of WMHs. CONCLUSION: WMHs are more common in migraine with aura. It is more frequent in migraine associated with vomiting and dizziness. WMHs increased with advancing age and more severe disease burden. Poorer response to acute and prophylactic medications was found in patients with WMHs.

Rs205764 and rs547311 in linc00513 may influence treatment responses in multiple sclerosis patients: A pharmacogenomics Egyptian study.

Background: Multiple sclerosis (MS) is characterized by a complex etiology that is reflected in the lack of consistently predictable treatment responses across patients of seemingly similar characteristics. Approaches to demystify the underlying predictors of aberrant treatment responses have made use of genome-wide association studies (GWAS), with imminent progress made in identifying single nucleotide polymorphisms (SNPs) associated with MS risk, disease progression, and treatment response. Ultimately, such pharmacogenomic studies aim to utilize the approach of personalized medicine to maximize patient benefit and minimize rate of disease progression. Objective: Very limited research is available around the long intergenic non-coding RNA (linc)00513, recently being reported as a novel positive regulator of the type-1 interferon (IFN) pathway, following its overexpression in the presence of two polymorphisms: rs205764 and rs547311 in the promoter region of this gene. We attempt to provide data on the prevalence of genetic variations at rs205764 and rs547311 in Egyptian MS patients, and correlate these polymorphisms with the patients' responses to disease-modifying treatments. Methods: Genomic DNA from 144 RRMS patients was isolated and analyzed for genotypes at the positions of interest on linc00513 using RT-qPCR. Genotype groups were compared with regards to their response to treatment; additional secondary clinical parameters including the estimated disability status score (EDSS), and onset of the disease were examined in relation to these polymorphisms. Results: Polymorphisms at rs205764 were associated with a significantly higher response to fingolimod and a significantly lower response to dimethylfumarate. Moreover, the average EDSS of patients carrying polymorphisms at rs547311 was significantly higher, whereas no correlation appeared to exist with the onset of MS. Conclusion: Understanding the complex interplay of factors influencing treatment response is pivotal in MS. One of the factors contributing to a patient's response to treatment, as well as disease disability, may be polymorphisms on non-coding genetic material, such as rs205764 and rs547311 on linc00513. Through this work, we propose that genetic polymorphisms may partially drive disease disability and inconsistent responses to treatment in MS; we also aim to draw attention towards genetic approaches, such as screening for specific polymorphisms, to possibly direct treatment choices in such a complex disease.

Microembolism versus hemodynamic impairment in rosary-like deep watershed infarcts: a combined positron emission tomography and transcranial Doppler study.

BACKGROUND AND PURPOSE: Deep watershed infarcts are frequent in high-grade carotid disease and are thought to result from hemodynamic impairment, particularly when adopting a rosary-like pattern. However, a role for microembolism has also been suggested, though never directly tested. Here, we studied the relationships among microembolic signals (MES) on transcranial Doppler, rosary-like deep watershed infarcts on brain imaging, and cerebral hemodynamic compromise on positron emission tomography (PET), all in severe symptomatic carotid disease. We hypothesized that rosary-like infarcts would be significantly associated with worse hemodynamic status, independent of the presence of MES. METHODS: Sixteen patients with ≥70% carotid disease ipsilateral to recent transient ischemic attack/minor stroke underwent magnetic resonance imaging including diffusion-weighted imaging, (15)O-PET, and transcranial Doppler. Mean transit time, a specific marker for hemodynamic impairment, was obtained in the symptomatic and unaffected hemispheres. RESULTS: Eleven of 16 patients had rosary-like infarcts (Rosary+) and 8 patients had MES. Mean transit time was significantly higher (P=0.008) in Rosary+ patients than in healthy controls (n=10), and prevalence of MES was not different between Rosary+ and Rosary- patients. Contrary to our hypothesis, however, the presence of MES within the Rosary+ subset was associated (P=0.03) with a better hemodynamic status than in their absence, with a significant (P=0.02) negative correlation between mean transit time and rate of MES/h. CONCLUSIONS: Contrary to mainstream understanding, rosary-like infarcts were not independent of presence and rate of MES, suggesting that microembolism plays a role in their pathogenesis, probably in association with hemodynamic impairment. Pending confirmation in a larger sample, these findings have management implications for patients with carotid disease and rosary-like infarcts.

Differential hemodynamic response to repetitive transcranial magnetic stimulation in acute stroke patients with cortical versus subcortical infarcts.

OBJECTIVE: To assess the cerebral vasomotor response to ipsilesional repetitive transcranial magnetic stimulation (rTMS) on transcranial Doppler (TCD) in patients with recent ischemic stroke without carotid occlusive disease, and to compare this response in patients with cortical and subcortical infarcts. METHODS: Consecutive patients with first-ever anterior circulation acute ischemic stroke (<3 days) and no extra- or intracranial arterial stenosis were prospectively recruited. Patients were divided into 2 groups: cortical infarct (CI, n = 15) and subcortical infarct (SI, n = 16). TCD cerebral blood flow velocity (CBFV) and pulsatility index were measured before and after 10-Hz suprathreshold rTMS over the dorsolateral prefrontal cortex. RESULTS: ANOVA showed a greater percentage increase in middle cerebral artery (MCA) CBFV in the SI group than in the CI group following rTMS (p = 0.01). The percentage change in CBFV was significantly correlated between both MCAs in SI patients but not in CI patients (r = 0.8, p < 0.001 vs. r = 0.05, p = 0.9, respectively). CONCLUSIONS: 10-Hz rTMS induces significant bilateral hemodynamic changes in patients with acute ischemic stroke, which appear to be less prominent and less synchronous in patients with cortical infarcts. These findings may allow optimization of the use of TMS in acute stroke.

Hemodynamic factors and perfusion abnormalities in early neurological deterioration.

BACKGROUND AND PURPOSE: Early neurological deterioration (END) is a relatively common unfavorable course after anterior circulation ischemic stroke that can lead to worse clinical outcome. None of the END predictors identified so far is sufficiently reliable to be used in clinical practice and the mechanisms underlying END are not fully understood. We review the evidence from the literature for a role of hemodynamic and perfusion abnormalities, more specifically infarction of the oligemia, in END: SUMMARY OF REVIEW: After an overview of the neuroimaging, including perfusion imaging, predictors of END, we review the putative mechanisms of END with a special focus on hemodynamic factors. The evidence relating perfusion abnormalities to END is addressed and potential hemodynamic mechanisms are suggested. CONCLUSIONS: Hemodynamic factors and perfusion abnormalities are likely to play a critical role in END: Infarction of the oligemic tissue surrounding the penumbra could be the putative culprit leading to END as a result of perfusion, but also physiological and biochemical abnormalities. Further studies addressing the role of the oligemia in END and developing measures to protect its progression to infarction are now needed.

Applications of nitroimidazole in vivo hypoxia imaging in ischemic stroke.

BACKGROUND AND PURPOSE: Nitroimidazole imaging is a promising contender for noninvasive in vivo mapping of brain hypoxia after stroke. However, there is a dearth of knowledge about the behavior of these compounds in the various pathophysiologic situations encountered in ischemic stroke. In this article we report the findings from a systematic review of the literature on the use of the nitroimidazoles to map hypoxia after stroke. SUMMARY OF REVIEW: We describe the characteristics of nitroimidazoles as imaging tracers, their pharmacology, and results of both animal and clinical studies during and after focal cerebral ischemia. Findings in brain tumors are also presented to the extent that they enlighten results in stroke. Early results from application of kinetic modeling for quantitative measurement of tracer binding are briefly discussed. CONCLUSIONS: Based on this literature review, nitroimidazole hypoxia imaging agents are of considerable interest in stroke because they appear, both in animal models and in humans, to specifically detect the severely hypoxic viable tissue, but not the reperfused nor the necrotic tissue. To fully realize this potential in stroke, however, formal validation by concurrent measurement of tissue oxygen tension, together with development of novel ligands with faster distribution kinetics, faster clearance from normal tissue, and well-defined trapping mechanisms, are important goals for future investigations.

Egyptian experience in increasing utilization of reperfusion therapies in acute ischemic stroke.

Background The rate of alteplase (tPA) thrombolysis utilization in acute stroke in Egypt is <1%. We report on the causes of this low rate of reperfusion therapies and take corrective action to improve it. Methods Two prospective observational studies were conducted at Ain Shams University hospitals. The first included 269 acute stroke patients admitted to the hospital over a six-month period. Obstacles to reperfusion therapy were identified, and based on the results, a corrective action plan was implemented including making alteplase(tPA) available, training, and establishing a standardized local protocol for reperfusion therapy. A second study was then conducted that included 284 acute ischemic stroke patients over another six-month period. Results In the first study, 53/269 patients (19.7%) arrived at hospital within 4.5 h and were eligible for reperfusion therapy. Of those, seven (13.2%) received alteplase(tPA), representing 2.6% of the total ischemic stroke patients admitted. The main causes for not giving thrombolytic therapy was unavailability of alteplase(tPA) (56.5%), wrong treatment decision (17.4%), missed window while performing brain imaging (15%), and unavailability of intermediate care bed (10.9%). The second study showed that out of 284 cases admitted with acute ischemic stroke, 37 were eligible for thrombolysis and 35 received alteplase(tPA) (94.3%), representing 12.3% of the total ischemic stroke admissions. Conclusion A comprehensive action plan that centers around making the drug available and training resulted in a significant improvement of reperfusion therapy utilization in Egypt.

Clinical review: Imaging in ischaemic stroke--implications for acute management.

Imaging has become a cornerstone of stroke management, translating pathophysiological knowledge to everyday decision-making. Plain computed tomography is widely available and remains the standard for initial assessment: the technique rules out haemorrhage, visualizes the occluding thrombus and identifies early tissue hypodensity and swelling, which have different implications for thrombolysis. Based on evidence from positron emission tomography (PET), however, multimodal imaging is increasingly advocated. Computed tomography perfusion and angiography provide information on the occlusion site, on recanalization and on the extent of salvageable tissue. Magnetic resonance-based diffusion-weighted imaging (DWI) has exquisite sensitivity for acute ischaemia, however, and there is increasingly robust evidence that DWI combined with perfusion-weighted magnetic resonance imaging (PWI) and angiography improves functional outcome by selecting appropriate patients for thrombolysis (small DWI lesion but large PWI defect) and by ruling out those who would receive no benefit or might be harmed (very large DWI lesion, no PWI defect), especially beyond the 3-hour time window. Combined DWI-PWI also helps predict malignant oedema formation and therefore helps guide selection for early brain decompression. Finally, DWI-PWI is increasingly used for patient selection in therapeutic trials. Although further methodological developments are awaited, implementing the individual pathophysiologic diagnosis based on multimodal imaging is already refining indications for thrombolysis and offers new opportunities for management of acute stroke patients.

Neuroscience research in Africa: Current status.

There are limited data on the contribution of the African continent to neuroscience research and publications. This review aims to provide a clear view on the state of neuroscience research among African countries, and to compare neuroscience research within the 52 African countries. A literature review search was conducted for all published articles by African authors in both local and international journals using Medline and other primary databases. Neuroscience represents 9.1% of the total medical publications. The highest percentage of neuroscience publications comes from South Africa. There is a positive correlation between the Gross Domestic Product and the total number of neuroscience publications among African countries. There is therefore an urgent need to develop strategies to improve neuroscience research in African countries.

Burden of stroke in Egypt: current status and opportunities.

Middle East and North Africa (MENA) countries have a diversity of populations with similar life style, dietary habits, and vascular risk factors that may influence stroke risk, prevalence, types, and disease burden. Egypt is the most populated nation in the Middle East with an estimated 85.5 million people. In Egypt, according to recent estimates, the overall prevalence rate of stroke is high with a crude prevalence rate of 963/100,000 inhabitants. In spite of disease burden, yet there is a huge evidence practice gap. The recommended treatments for ischemic stroke that are guideline include systematic supportive care in a stroke unit or stroke center is still deficient. In addition, the frequency of thrombolysis in Egypt is very low for many reasons; the major one is that the health insurance system is not covering thrombolysis therapy in nonprivate sectors so patients must cover the costs using their own personal savings; otherwise, they will not receive treatment. Another important factor is the pronounced delay in prehospital and in hospital management of acute stroke. Improvement of stroke care in Egypt should be achieved through multi and interdisciplinary approach including public awareness, physicians' education, and synergistic approach to stroke care with Emergency Medical System.

Carotid plaque inflammation is associated with cerebral microembolism in patients with recent transient ischemic attack or stroke: a pilot study.

BACKGROUND: Cerebral infarcts distal to carotid stenoses are thought to be caused by emboli from inflamed, destabilized plaques. We hypothesized that microembolic signals (MES) on transcranial Doppler will be associated with carotid plaque inflammation on (18)F fluorodeoxyglucose positron-emission tomography (FDG PET) in recently symptomatic patients. METHODS AND RESULTS: Sixteen patients presenting with recent (47 ± 31 days) anterior circulation transient ischemic attack or minor stroke and 50% to 99% stenosis of the ipsilateral carotid bifurcation underwent FDG PET, high-resolution black-blood carotid MRI, and transcranial Doppler for detection of MES. Patients with potential cardiac sources of emboli or contralateral MES were excluded. Regions of interest defined on the coregistered MRI were used to measure FDG standardized uptake values (with Rousset partial volume correction) from the index and contralateral carotid plaques and artery. Ipsilateral MES were detected in 7 patients (MES+ group) and absent in 8 (MES- group). There was a significant difference in index-to-contralateral plaque standardized uptake value ratio between MES+ (median, 1.05; first to third quartile, 0.96 to 1.32) and MES- (median, 0.76; first to third quartile, 0.62 to 0.94) patients (P=0.005). The interval from symptom onset to PET and percent index carotid stenosis were not different between the 2 groups (P=0.68 and P=0.48, respectively). CONCLUSIONS: In this sample of recently symptomatic patients with carotid stenosis, an association was found between in vivo measures of plaque inflammation detected by FDG PET and the presence of transcranial Doppler MES. These findings strengthen the notion that embolic events distal to carotid stenoses are related to plaque inflammation, and FDG PET may be useful in the investigation of culprit carotid lesions.