Low-level stochastic vestibular stimulation (SVS) has been associated with improved postural responses in the medio-lateral (ML) direction, but its effect in improving balance function in both the ML and anterior-posterior (AP) directions has not been studied. In this series of studies, the efficacy of applying low amplitude SVS in 0–30 Hz range between the mastoids in the ML direction on improving cross-planar balance function was investigated. Forty-five (45) subjects stood on a compliant surface with their eyes closed and were instructed to maintain a stable upright stance. Measures of stability of the head, trunk, and whole body were quantified in ML, AP and combined APML directions. Results show that binaural bipolar SVS given in the ML direction significantly improved balance performance with the peak of optimal stimulus amplitude predominantly in the range of 100–500 μA for all the three directions, exhibiting stochastic resonance (SR) phenomenon. Objective perceptual and body motion thresholds as estimates of internal noise while subjects sat on a chair with their eyes closed and were given 1 Hz bipolar binaural sinusoidal electrical stimuli were also measured. In general, there was no significant difference between estimates of perceptual and body motion thresholds. The average optimal SVS amplitude that improved balance performance (peak SVS amplitude normalized to perceptual threshold) was estimated to be 46% in ML, 53% in AP, and 50% in APML directions. A miniature patch-type SVS device may be useful to improve balance function in people with disabilities due to aging, Parkinson’s disease or in astronauts returning from long-duration space flight.

Purpose: Ongoing post-stroke structural degeneration and neuronal loss preceding neuropsychological symptoms such as cognitive decline and depression are poorly understood. Various substructures of the limbic system have been linked to cognitive impairment. In this longitudinal study, we investigated the post-stroke macro- and micro-structural integrity of the limbic system using structural and diffusion tensor magnetic resonance imaging.Materials and Methods: Nineteen ischemic stroke patients (11 men, 8 women, average age 53.4 ± 12.3, range 18–75 years), with lesions remote from the limbic system, were serially imaged three times over 1 year. Structural and diffusion-tensor images (DTI) were obtained on a 3.0 T MRI system. The cortical thickness, subcortical volume, mean diffusivity (MD), and fractional anisotropy (FA) were measured in eight different regions of the limbic system. The National Institutes of Health Stroke Scale (NIHSS) was used for clinical assessment. A mixed model for multiple factors was used for statistical analysis, and p-values <0.05 was considered significant.Results: All patients demonstrated improved NIHSS values over time. The ipsilesional subcortical volumes of the thalamus, hippocampus, and amygdala significantly decreased (p < 0.05) and MD significantly increased (p < 0.05). The ipsilesional cortical thickness of the entorhinal and perirhinal cortices was significantly smaller than the contralesional hemisphere at 12 months (p < 0.05). The cortical thickness of the cingulate gyrus at 12 months was significantly decreased at the caudal and isthmus regions as compared to the 1 month assessment (p < 0.05). The cingulum fibers had elevated MD at the ipsilesional caudal-anterior and posterior regions compared to the corresponding contralesional regions.Conclusion: Despite the decreasing NIHSS scores, we found ongoing unilateral neuronal loss/secondary degeneration in the limbic system, irrespective of the lesion location. These results suggest a possible anatomical basis for post stroke psychiatric complications.

Background: First pass complete or near complete reperfusion defined as a modified Thrombolysis in Cerebral Infarction (mTICI) 2c/3 is the target for endovascular thrombectomy (EVT). Here, we examine whether additional passes in patients who achieve a first pass mTICI 2b, in order to attain mTICI 2c/3, improve clinical outcomes. Methods: From our prospectively maintained institutional registry at 4 comprehensive stroke centers, we identified patients treated with EVT (11/2017-12/2021). Per-pass mTICI grades were recorded at the time of the procedure. The primary outcome was functional independence rates at 90 days (mRS 0-2) in first pass mTICI 2b patients compared with multiple passes mTICI 2c/3 patients. Results: A total of 857 EVT patients were identified in the study period. The median age was 68 [58-79], 49.7% were female, median NIHSS was 16 [11-21], median ASPECTS was 9 [7-10], and 64% had MCA occlusions. First pass mTICI 2c/3 (FP-mTICI 2c/3) was achieved in 342 (39.9%) cases and first pass mTICI 2b (FP-mTICI 2b) was achieved in 123 (14.4%) patients. Of the FP-mTICI 2b group, 27 (21.9%) patients received additional passes to reach complete reperfusion. Good functional outcome was observed in 159 patients (46.5%) of the FP-mTICI 2c/3 reperfusion group as compared to 27 patients (28.1%) in the FP-mTICI 2b group (p=0.002). The rate of good functional outcome was not significantly different for patients who achieved mTICI 2c/3 following additional passes after a first pass mTICI 2b (28.1 vs. 29.6%, first pass mTICI 2b vs. first pass mTICI 2b with final mTICI 2c/3, p=0.954). Adjusted for age, sex and NIHSS at presentation, patients with FP-mTICI 2c/3 had a better chance of good outcomes than patients with FP-mTICI 2b (OR 2.23, 95% CI [1.38-3.62]). In multivariable analysis adjusting for age, sex, and NIHSS at presentation, patients with FP-mTICI 2b reperfusion followed by improved reperfusion to mTICI 2c/3 did not have better outcomes than patients with FP-mTICI 2b reperfusion (OR 1.14, 95% CI [0.41-3.12]). Conclusions: Additional EVT passes to achieve mTICI 2c/3 following a first pass mTICI 2b does not lead to significant improvement in functional outcomes. This study suggests that EVT can be terminated if FP-mTICI 2b-3 is achieved.

Background: Recent studies have shown that tPA can be safely administered past the standard 4.5hr window with good outcomes when selected with multi-model imaging, which is often lacking outside of comprehensive stroke centers. Aim: We aim to analyze the safety and outcomes of wake up/unknown onset (WUS/UNK) patients treated based on non-contrast head CT (NCCT) at our institution and in the literature. Methods: Suspected stroke patients from 01/2015-12/2018 receiving tPA within 4.5 hours (standard window-SW) and with WUS/UNK based on NCCT and clinical-imaging mismatch were identified. We compared baseline characteristics, tPA metrics, and outcome data, with primary outcome as symptomatic intracerebral hemorrhage (sICH). A meta-analysis was performed evaluating NCCT-based treatment of WUS/UNK patients. Results: Of 1827 patients treated at our hub or through telestroke, 93 underwent WUS/UNK-based treatment. There was no statistical difference in sICH between WUS/UNK and SW: 1% vs 4% (OR 0.3; 95% confidence interval 0.0-1.9). 90-day modified Rankin scale outcomes were similar between SW and WUS/UNK treated patients. Seven studies encompassing 485 WUS/UNK patients were included in a pooled analysis with a 2.1% incidence of sICH. In our meta-analysis, three studies compared NCCT-based treated WUS/UNK patients with SW patients with no difference in rate of hemorrhage: 2.1% vs 3.4% (OR 1.01; 95% confidence interval 0.45-2.28). Interpretation: Our single-center analysis and meta-analysis suggest that tPA can be safely administered based on NCCT with comparable rates of sICH for select WUS/UNK stroke patients.

Introduction: The relationship between pass number during endovascular therapy (EVT) and outcomes in anterior circulation large vessel occlusion (LVO) acute ischemic stroke (AIS) has been well studied. However, the association between number of thrombectomy attempts and outcomes for patients with posterior circulation LVO remains undetermined. Methods: From our prospective multi-institutional registry including 4 comprehensive stroke centers in the Houston area, we identified consecutive LVO AIS patients who underwent EVT (01/2018-06/2021). The number of thrombectomy passes and per-pass reperfusion grades (TICI) were recorded at time of the EVT procedure. The primary outcome was the effect of number of passes on functional independence (modified Rankin Scale 0-2) at 90 days. Secondary outcomes included likelihood of attaining substantial reperfusion (TICI ≥2b). Results: Among 894 LVO AIS patients who underwent EVT, median age was 68 [IQR 58-78], 49% were female, and median NIHSS was 16 [IQR 11-21]. Of this cohort, 86 had posterior circulation LVO including 65 with basilar artery occlusion and 9 vertebral artery. The diminishing benefit on reperfusion and functional outcome after additional EVT passes was similar for anterior and posterior circulation AIS (Figure 1). Among patients with posterior circulation LVO, successful reperfusion with fewer passes was associated with greater likelihood of good outcomes (41.9% vs 6.7% mRS 0-2 with 1-2 vs ≥3, p=0.012). The likelihood of good outcomes with 1-2 passes for patients with posterior circulation LVO was comparable to patients with anterior circulation LVO (41.9% vs 40.2%, p=0.164). Conclusions: Similar to patients with anterior circulation LVO, patients with posterior circulation LVO undergoing EVT are more likely to achieve functional independence with successful reperfusion in fewer EVT attempts. Overall clinical outcomes are significantly better with fewer passes regardless of occlusion location.