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Background and Purpose: Quantitative CT perfusion (CTP) thresholds for assessing the extent of ischemia in patients with acute ischemic stroke (AIS) have been established; relative cerebral blood flow (rCBF) <30% is typically used for estimating estimated ischemic core volume and Tmax (time to maximum) >6 seconds for critical hypoperfused volume in AIS patients with large vessel occlusion (LVO). In this study, we aimed to identify the optimal threshold values for patients presenting with AIS secondary to distal medium vessel occlusions (DMVOs). Methods: In this retrospective study, consecutive AIS patients with anterior circulation DMVO who underwent pretreatment CTP and follow‐up MRI/CT were included. The CTP data were processed by RAPID (iSchemaView, Menlo Park, CA) to generate estimated ischemic core volumes using rCBF <20%, <30%, <34%, and <38% and critical hypoperfused volumes using Tmax (seconds) >4, >6, >8, and >10. Final infarct volumes (FIVs) were obtained from follow‐up MRI/CT within 5 days of symptom onset. Diagnostic performance between CTP thresholds and FIV was assessed in the successfully and unsuccessfully recanalized groups. Results: Fifty‐five patients met our inclusion criteria (32 female [58.2%], 68.0 ± 12.1 years old [mean ± SD]). Recanalization was attempted with intravenous tissue‐type plasminogen activator and mechanical thrombectomy in 27.7% and 38.1% of patients, respectively. Twenty‐five patients (45.4%) were successfully recanalized. In the successfully recanalized patients, no CTP threshold significantly outperformed what is used in LVO setting (rCBF < 30%). All rCBF CTP thresholds demonstrated fair diagnostic performances for predicting FIV. In unsuccessfully recanalized patients, all Tmax CTP thresholds strongly predicted FIV with relative superiority of Tmax >10 seconds (area under the receiver operating characteristic curve =.875, p =.001). Conclusion: In AIS patients with DMVOs, longer Tmax delays than Tmax > 6 seconds, most notably, Tmax > 10 seconds, best predict FIV in unsuccessfully recanalized patients. No CTP threshold reliably predicts FIV in the successfully recanalized group nor significantly outperformed rCBF < 30%. [ABSTRACT FROM AUTHOR]

Background and Purpose: Minor acute ischemic stroke (AIS) patients—defined by an NIHSS score < 6—presenting with proximal middle cerebral artery large vessel occlusions (MCA-LVO) is a subgroup for which treatment is still debated. Although these patients present with minor symptoms initially, studies have shown that several patients afflicted with MCA-LVO in this subgroup experience cognitive and functional decline. Although mechanical thrombectomy (MT) is the standard of care for patients with an NIHSS score of 6 or higher, treatment in the minor stroke subgroup is still being explored. The purpose of this preliminary study is to report our center's experience in evaluating the potential benefit of mechanical thrombectomy (MT) in minor stroke patients when compared to medical management (MM). Methods: We performed a retrospective study with two comprehensive stroke centers within our hospital enterprise of consecutive patients presenting with minor AIS secondary to MCA-LVO (defined as M1 or proximal M2 segments of MCA). We subsequently evaluated patients who received MT versus those who received MM. Results: Between January 2017 and July 2021, we identified 46 AIS patients (11 treated with MT and 35 treated with MM) who presented with an NIHSS score < 6 secondary to MCA-LVO (47.8% 22/46 female, mean age 62.3 years, range 49–75 years). MT was associated with a significantly lower mRS at 90 days (median: 1.0 [IQR 0.0–2.0] versus 3.0 [IQR 1.0–4.0], p = <0.001), a favorable NIHSS shift (−4.0 [IQR −10.0–−2.0] versus 0.0 [IQR −2.0–1.0], p = 0.002), favorable NIHSS shift dichotomization (5/11, 45.5% versus 3/35, 8.6%, p = 0.003) and favorable mRS dichotomization (7/11, 63.6% versus 14/35, 40.0%, p = 0.024). Conclusions: In our center's preliminary experience, for AIS patients presenting with an NIHSS score < 6 secondary to MCA-LVO, MT may be associated with improved clinical outcomes when compared to MM only. [ABSTRACT FROM AUTHOR]

Objective Methods Results Interpretation Strokes involving sensory pathways can result in contralesional pain syndromes often refractory to pharmacologic interventions. Scrambler therapy (ST) is a noninvasive electroanalgesia device used to treat pain caused by peripheral neuropathy; however, data are scarce regarding its use in conditions secondary to central nervous system pathology. We evaluate the efficacy of ST to treat poststroke pain.Twenty patients with a history of prior stroke resulting in contralesional pain were randomized to receive ST or Sham as an adjunct to their stable medication regimen. Participants underwent 5 consecutive daily 40‐min sessions. The study was blinded to patient and assessor. Pain scores (0–10) were recorded at baseline, pre‐ and postsession, and 4 weeks after final treatment. Student's t‐tests compared differences in the mean change in pain score between groups immediately post‐treatment #5, and at 4‐weeks. The chi‐squared analysis compared the proportion of patients in each group with >50% pain reduction.Participants randomized to ST had a mean change in pain score of −3.73 (SD 2.85) postintervention and −2.57 (SD 2.07) at 4 weeks, while the Sham group had a mean change in score of −0.94 (SD 1.36) and −0.25 (SD 0.84) (p between groups = 0.012, 0.004, respectively). Significantly more participants treated with ST reported a >50% reduction in pain immediately postintervention compared to Sham (70% vs. 10%, p = 0.006), but not at follow‐up (30% vs. 10%, p = ns).ST may effectively decrease poststroke pain compared to Sham. Larger studies are needed to evaluate confounders such as stroke location, time from stroke, and concomitant treatment with medications. [ABSTRACT FROM AUTHOR]

Intravenous tissue plasminogen activator is the mainstay for the treatment of acute ischemic stroke in patients presenting within 4.5 h of symptom onset. Studies have demonstrated that treating patients early leads to improved long-term outcomes. MR imaging currently allows quantification of the ischemic penumbra in order to better identify individuals most likely to benefit from intervention, irrespective of "time last seen normal." Its increasing use in clinical practice has demonstrated individual differences in rate of infarction. One explanation for this variability is a difference in collateral blood flow. We report two cases that highlight the individual variability of infarction rate, and discuss potential underlying mechanisms that may influence treatment decisions and outcomes. [ABSTRACT FROM AUTHOR]

Background : Previous studies have indicated that focal brain damage can result in different types of “neglect dyslexia” (reading errors specific to the side of printed material contralateral to the side of brain damage). Aims : To identify the sites of lesions (or dysfunctional brain tissue) responsible for distinct types of neglect dyslexia, to inform a functional neuroanatomical model of brain regions involved in early stages of reading. Methods & Procedures : A battery of tests of hemispatial neglect and reading designed to distinguish neglect dyslexia in different reference frames (viewer-centred, stimulus-centred, and object-centred) was administered to 95 patients within 48 hours of onset of nondominant hemisphere stroke. Magnetic resonance diffusion and perfusion imaging was obtained on the same day as testing. Associations between each type of neglect dyslexia and areas of hypoperfusion and/or infarct were evaluated using chi-squared tests. Outcomes & Results : Viewer-centred neglect dyslexia was associated with hypoperfusion and/or infarct in right angular and supramarginal gyri and visual association cortex (“dorsal stream”). Stimulus-centred neglect dyslexia was associated with hypoperfusion and/or infarct of right superior temporal cortex (“ventral stream”). Object-centred neglect dyslexia was observed only with hypoperfusion and/or infarct of non-dominant superior temporal cortex in left-handed individuals. Conclusions : The identified associations provide evidence that different regions of cortex are critical for spatial attention to, or processing of, representations of words with distinct coordinate frames in the reading task. [ABSTRACT FROM AUTHOR]