The Clinical Impact of Recent Methamphetamine Exposure in Aneurysmal Subarachnoid Patients.

Background: Methamphetamines (MA) are a frequently used drug class with potent sympathomimetic properties that can affect cerebral vasculature. Conflicting reports in literature exist about the effect of exposure to MA on vasospasm risk and clinical outcomes in aneurysmal subarachnoid hemorrhage (aSAH). This study aimed to characterize the impact of recent MA use on the timing, severity and features of vasospasm in aneurysmal subarachnoid as well as neurological outcomes. Methods: We retrospectively screened 441 consecutive patients admitted to a tertiary care hospital with a diagnosis of SAH who underwent at least one cerebral digital subtraction angiogram (DSA). Patients were excluded if no urinary toxicology screen was performed within 24 hours of admission, if there was a diagnosis of non-aneurysmal SAH, or if ictus was greater than 72 hours from hospital admission. Vasospasm characteristics were collected from DSA and transcranial doppler (TCD) studies and demographic as well as clinical outcome data was abstracted from the chart. Results: 129 patients were included and 24 tested positive for MA. Among the 312 excluded patients, 281 did not have a urinary toxicology screen and 31 had a non-aneurysmal pattern of SAH or ictus occurring greater than 72 hours from hospital admission. No significant differences were found in respect to patient age, sex, or admission Hunt and Hess Score or Modified Fisher Scale based on MA use. There was no difference in the severity of vasospasm or time to peak severity using either TCD or DSA criteria on multivariate analysis. Aneurysms were more likely to be in the anterior circulation for both groups, however the MA cohort experienced less vasospasm involving the anterior circulation and more isolated posterior circulation vasospasm. There was no difference in delayed cerebral ischemia (DCI) incidence, length of ICU stay, need for ventriculoperitoneal shunt placement, functional outcome at discharge or hospital mortality. Interpretation: Recent MA use was not associated with worse vasospasm severity, time to vasospasm, or DCI in aSAH patients. Further investigations about localized MA effects in the posterior circulation and impact on long-term functional outcomes are warranted.

Outcomes and Spectrum of Major Neurovascular Events Among COVID-19 Patients: A 3-Center Experience.

BACKGROUND: Preliminary data suggest that Coronavirus Disease-2019 (COVID-19) is associated with hypercoagulability and neurovascular events, but data on outcomes is limited. OBJECTIVE: To report the clinical course and outcomes of a case series of COVID-19 patients with a variety of cerebrovascular events. METHODS: We performed a multicentric, retrospective chart review at our three academic tertiary care hospitals, and identified all COVID-19 patients with cerebrovascular events requiring neuro-intensive care and/or neurosurgical consultation. RESULTS: We identified 26 patients between March 1 and May 24, 2020, of whom 12 (46%) died. The most common event was a large-vessel occlusion (LVO) in 15 patients (58%), among whom 8 died (8/15, 53%). A total of 9 LVO patients underwent mechanical thrombectomy, of whom 5 died (5/9, 56%). A total of 7 patients (27%) presented with intracranial hemorrhage. Of the remaining patients, 2 had small-vessel occlusions, 1 had cerebral venous sinus thrombosis, and another had a vertebral artery dissection. Acute Respiratory Distress Syndrome occurred in 8 patients, of whom 7 died. Mortalities had a higher D-dimer on admission (mean 20 963 ng/mL) than survivors (mean 3172 ng/mL). Admission Glasgow Coma Scale (GCS) score was poor among mortalities (median 7), whereas survivors had a favorable GCS at presentation (median 14) and at discharge (median 14). CONCLUSION: COVID-19 may be associated with hemorrhage as well as ischemia, and prognosis appears poorer than expected-particularly among LVO cases, where outcome remained poor despite mechanical thrombectomy. However, a favorable neurological condition on admission and lower D-dimer may indicate a better outcome.

Vertical head translation impairs dynamic visual acuity during near viewing.

Dynamic visual acuity is an important clinical tool for assessment of the rotational vestibulo-ocular reflex (rVOR). It is based on the fact that the normal rVOR stabilizes vision and maintains visual acuity during head rotation. The translational VOR (tVOR) generates eye movements during linear head motion. Studies in humans have shown that gaze stabilization during translation is incomplete and that there is a strong effect of the visual environment: eye velocity is much greater in the light than in the dark. In this study, we measured visual acuity during vertical translation in 11 subjects and asked whether a more complex visual background would enhance the response and improve acuity. During 2 Hz whole-body translation, tumbling-E optotypes (0.0-0.9 logMAR in steps of 0.1 logMAR, six trials of each size randomly ordered) were flashed on a screen that was 30 cm in front of the subject's eyes. The subject reported the optotype's orientation with a joystick. Based on a threshold of 75% trials correctly identified, the group dynamic acuity was 0.72 logMAR, compared to a static acuity of 0.0 logMAR. When the background was enhanced with a stationary dot pattern, dynamic acuity improved to 0.42 logMAR. Our findings show that vertical head translation degrades vision more than head rotation. This may limit the use of dynamic acuity as a clinical measure of otolith function.