No abstract

No abstract

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.

No abstract

No abstract

Date Palm Rachis has been widely used in sheathing of houses in the rural communities in Egypt and the Middle East, as a local and cheap material that naturally resists direct solar radiation and humidity. Lately, researchers around the world began to build complete structures using Date Palm Rachis to take advantage of its abundance and natural resistance. However, due to the lack of the required mechanical properties for structural analytical modeling, mock ups are used to assess the structural properties of Date Palm Rachis. This tool of assessment is insufficient in the consideration of wind or temporary and unforeseen loads. This paper introduces the closest estimations of the complicated mechanical properties required for structural analytical modeling, according to the available equipment and the variable nature of Date Palm Rachis. The results showed that Date Palm Rachis is a promising structural material with structural properties that are competitive to that of imported timbers in Egypt. This paper invites researches and builders to exploit the potentials of Palm Rachis as a structural material for rural communities.

Background: Cerebral microbleeds are small, round dark-signal foci in the T2 *-weighted magnetic resonance imaging. They are encountered in cerebral amyloid angiopathy and hypertensive vasculopathy. Their prevalence is common in ischemic stroke and cerebral hemorrhage. The purpose of this study is to investigate the prevalence of CMBs and associated risk factors in the elderly patients with acute ischemic stroke. Results: Cerebral microbleeds were significantly associated with the presence of hypertension (in the subgroup of recurrent stroke) and with hypercholesterolemia. There was a significant association between the number of the microbleeds and severity of white matter lesions as a higher number of microbleeds related to more severe white matter lesions. The microbleeds were more prevalent in the group of patients using antithrombotics. Conclusion: Age, hypercholesterolemia, and the use of antithrombotics emerged as the most important associated risk factors for the presence of CMBs. On MRI, there was a significant association between the number of CMBs and severity of white matter lesions as a higher number of CMBs related to more severe white matter lesions.

BACKGROUND AND PURPOSE:The current Neck Imaging Reporting and Data System (NI-RADS) criteria were designed for contrastenhanced CT with or without PET. Prior studies have revealed the capability of DWI and T2 signal intensity in distinguishing locoregional tumor residual and recurrence from posttreatment benign findings in head and neck cancers. We aimed to propose MR imaging NI-RADS criteria by adding diffusion criteria and T2 signal intensity to the American College of Radiology NI-RADS template. MATERIALS AND METHODS:This retrospective study included 69 patients with head and neck squamous cell carcinoma (HNSCC) who underwent posttreatment contrast-enhanced MRI imaging surveillance using a 1.5T scanner. The scans were interpreted by 2 neuroradiologists. Image analysis assessed the primary tumor site using the current American College of Radiology NI-RADS morphologic lexicon (mainly designed for contrast-enhanced CT with or without PET). NI-RADS rescoring was then performed based on our proposed criteria using T2 signal and diffusion features. The reference standard was a defined set of criteria, including clinical and imaging follow-up and pathologic assessment.RESULTS: Imaging assessment of treated HNSCC at the primary tumor site using T2 signal intensity and diffusion features as modifying rules to NI-RADS showed higher sensitivity, specificity, positive predictive value, negative predictive value, and accuracy (92.3%, 90.7%, 85.7%, 95.1%, and 91.3%, respectively) compared with the current NI-RADS lexicon alone (84.6%, 81.4%, 73.3%, 89.8%, and 82.6%, respectively). CONCLUSIONS:The addition of diffusion features and T2 signal to the American College of Radiology NI-RADS criteria for the primary tumor site enhances the specificity, sensitivity, positive predictive value, negative predictive value, and NI-RADS accuracy.