Journal of neuroimaging : official journal of the American Society of Neuroimaging
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Cerebral vasospasm in the setting of subarachnoid hemorrhage causes morbidity and mortality due to delayed cerebral ischemia and permanent neurological deficits. Vasospasm treatment includes intra-arterial injection of a spasmolytic during cerebral angiography. To evaluate effectiveness, neurointerventionalists subjectively examine a posttreatment cerebral angiogram to determine change in vessel diameter or increase in microvascular perfusion. Flat-detector computed tomography (FDCT) scanner has the ability to quantitatively measure cerebral blood volume (CBV) within the parenchyma and detect a quantitative change following treatment. ⋯ In conclusion, FDCT could measure the effectiveness of a change in CBV from infusion of verapamil in the setting of cerebral vasospasm. The authors believe quantifying the change allows for reassurance of improvement of cerebral vasospasm.
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Comparative Study
Noncontrast CT versus Perfusion-Based Core Estimation in Large Vessel Occlusion: The Blood Pressure after Endovascular Stroke Therapy Study.
The 2018 AHA guidelines recommend perfusion imaging to select patients with acute large vessel occlusion (LVO) for thrombectomy in the extended window. However, the relationship between noncontrast CT and CT perfusion imaging has not been sufficiently characterized >6 hours after last known normal (LKN). ⋯ In this multicenter prospective cohort of patients who underwent thrombectomy, one-third of patients had normal CTP core volumes despite nearly three quarters of patients showing ischemic changes on CT. This finding emphasizes the need to carefully assess both noncontrast and perfusion imaging when considering thrombectomy eligibility.
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Corpus callosum atrophy is a neurodegenerative biomarker in multiple sclerosis (MS). Manual delineations are gold standard but subjective and labor intensive. Novel automated methods are promising but require validation. We aimed to compare the robustness of manual versus automatic corpus callosum segmentations based on FreeSurfer. ⋯ FreeSurfer's longitudinal stream provides corpus callosum measures with better repeatability than current manual methods and with similar clinical correlations. However, due to some limitations in accuracy, caution is warranted when using FreeSurfer with clinical data.
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Microembolic signals (MES) are detectable by transcranial Doppler monitoring and associated with increased risk of first or recurrent ischemic stroke. MES detection can also illuminate stroke etiology and the effect of prophylactic treatment. MES detection cannot accurately distinguish between stroke-related microemboli and ultrasound contrast agents. These agents contain microbubbles and are frequently used in neuro- and cardiovascular diagnostics. We aimed to assess how long after contrast infusion microbubbles are detectable by transcranial Doppler monitoring. ⋯ None of the subjects had detectable MES for more than 77 minutes after ultrasound contrast infusion. MES detection with the intent to detect stroke-related microemboli should wait for at least this long after completed infusion.
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Over the course of treatment for Parkinson's disease (PD), the clinical effects of dopaminergic medication diminish and side effects emerge. Therefore, searching for new therapeutic alternatives or complementary treatments is required. Transcranial direct current stimulation (tDCS) could potentially complement the current therapeutic armamentarium, but only a few studies have investigated the therapeutic effects of tDCS in PD. The present pilot study aimed to investigate the effects of repeated tDCS treatment on motor symptoms and regional cerebral blood flow (rCBF) in patients with PD using single photon emission computed tomography (SPECT). ⋯ This study shows that tDCS application may improve rCBF in the frontal and parietal lobes in patients with PD, suggesting beneficial effects of tDCS on brain function. Our results are preliminary and further large-scale studies are needed to confirm our findings.