Mapping the ischemic penumbra and predicting stroke progression in acute ischemic stroke: the overlooked role of susceptibility weighted imaging.

OBJECTIVES: Asymmetrically prominent veins (APVs) detected on susceptibility weighted imaging (SWI) in acute stroke patients are assumed to signify compromised cerebral perfusion. We aimed to explore the role of APVs in identifying the ischemic penumbra and predicting stroke progression in acute stroke patients METHODS: Twenty patients with a middle cerebral artery ischemic infarction presenting within 24 h of symptoms onset underwent SWI following our standard MR stroke protocol imaging sequences which included diffusion-weighted imaging (DWI). Follow-up (FUP) FLAIR images were obtained at least 5 days after the initial MRI study. The Alberta Stroke Program Early CT Score (ASPECTS) was used to determine the initial infarct size, extent of APVs and final infarct size on initial DWI, SWI, and FUP images respectively. For each patient, SWI was compared with DWI images to determine match/mismatch of their respective ASPECTS values and calculate mismatch scores, whereas acute DWI findings were compared with follow-up images to identify infarct growth (IG) and calculate infarction growth scores (IGS). RESULTS: IG occurred in 6/10 patients with a positive DWI-SWI mismatch and in none of the patients without a positive DWI-SWI mismatch. A positive DWI/SWI mismatch was significantly associated with IG (χ2 = 8.57, p = 0.0138, Cramer's V = 0.65). A significant inverse correlation was found between SWI ASPECTS and IGS (rs = - 0.702, p = 0.001). DWI-SWI mismatch scores were strongly correlated with IGS. (rs = 0.788, p = 0.000) CONCLUSION: A positive DWI-SWI mismatch is an indicator of the ischemic penumbra and a predictor of infarct expansion if left untreated.

Magnetic resonance imaging markers of disability in Egyptian multiple sclerosis patients.

BACKGROUND: The aim of this work was to identify the magnetic resonance imaging (MRI) markers of disability in Egyptian multiple sclerosis (MS) patients. SUBJECTS AND METHODS: This retrospective observational study included 673 patients recruited from the registry of the MS unit at Ain Shams University hospitals. At the time when the MRI scans of the brain and spinal cord were done (with and without gadolinium enhancement), clinical disability was rated using the Expanded Disability Status Scale (EDSS) during the patient's first visit. RESULTS: Females represented 72.5%, all types of MS were included, the mean age of onset was 26.1 ±â€¯7.7(SD) years, mean duration of illness was 8.3 ±â€¯5.5(SD) years. The mean EDSS of the patients was 3.5 ±â€¯2.1. The study population was divided into three groups according to the EDSS score; mild from 0-3 (56.6%), moderate from 3.5-6 (34.9%) and severe more than 6 (8.5%). The number and types of MRI lesions (T2, T1 black holes, T1 contrast and confluent lesions) in the different anatomical locations (periventricular, juxtacortical, infratentorial and spinal) were correlated with the clinical and demographic data of the patients as well as with the EDSS score. The presence of confluent brain lesions (P Ë‚ 0.001), brain T1 hypointense lesions (P = 0.009), and infratentorial T2 lesions (from 1 to 3 lesions (P = 0.04), from 4 to 10 (P ˂ 0.001) and more than 10 (P ˂ 0.001)), were significantly correlated to high EDSS scores after linear regression analysis. CONCLUSION: This is the first Egyptian study to show that infratentorial lesions, confluent brain lesions and T1 hypointense lesions are conventional MRI parameters that correlate with the degree of disability in Egyptian MS patients.