Abstract Number ‐ 239: Subcortical Infarcts in Patients with Nonstenotic Cervical Atherosclerotic Disease

Introduction Prior studies have elucidated a relationship between nonstenotic plaque in patients with cryptogenic embolic (cortical) infarcts, however it is unclear if nonstenotic carotid plaque is relevant in subcortical infarct patterns. Methods A nested cohort of consecutive patients with anterior, unilateral, subcortical infarcts without an identifiable embolic source were identified from a prospective stroke registry (September 2019 ‐ June 2021). Patients with extracranial stenosis >50% were excluded. Patients with computed tomography angiography were included and comparisons made according to infarct pattern being lacunar (single lesion < 1.5cm on computed tomography [CT] or < 2.0cm on diffusion weighted imaging [DWI]) versus cryptogenic (≥ 1.5cm on CT or ≥ 2.0cm on DWI, or scattered subcortical lesions). Prevalence estimates for cervical internal carotid artery (ICA) plaque presence were estimated with 95% confidence intervals (CI), and differences in plaque thickness and features were compared between sides. Results Of the 1684 who were screened, 141 met inclusion criteria (n = 80 due to small vessel disease, n = 61 cryptogenic). The median age was 66y (interquartile range, IQR 58–73) and National Institutes of Health Stroke Scale score was 3 (IQR 1–5). There was a higher probability of finding excess plaque ipsilateral to the stroke (41.1%, 95%CI 33.3‐49.3%) than finding excess contralateral plaque (29.1%, 95%CI 22.2‐37.1%; p = 0.03), but this was driven by patients with cryptogenic infarcts (excess ipsilateral vs. contralateral plaque frequency of 49.2% vs. 14.8%, p< 0.001) and not lacunar disease (35.0% vs. 40.0%, p = 0.51). Conclusions The probability of finding ipsilateral, nonstenotic carotid plaque in patients with subcortical cryptogenic strokes exceeds the probability of contralateral plaque and is driven by larger subcortical infarcts, classically defined as being cryptogenic. Approximately 1 in 3 unilateral anterior subcortical infarcts may be due to nonstenotic ICA plaque

Summary of environmental characterization activities at the Oak Ridge National Laboratory Solid Waste Storage Area Six, FY 1986 through 1987

The Oak Ridge National Laboratory (ORNL) Remedial Action Program (RAP), has supported characterization activities in Solid Waste Storage Area (SWSA 6) to acquire information necessary for identification and planning of remedial actions that may be warranted, and to facilitate eventual closure of the site. In FY 1986 investigations began in the areas of site hydrology, geochemistry, soils, geology, and geohydrologic model application. This report summarizes work carried out in each of these areas during FY's 1986 and 1987 and serves as a status report pulling together the large volume of data that has resulted. Characterization efforts are by no means completed; however, a sufficient data base has been generated to begin data interpretation and analysis of site contaminants

An interstitial deletion-insertion involving chromosomes 2p25.3 and Xq27.1, near SOX3, causes X-linked recessive hypoparathyroidism.

X-linked recessive hypoparathyroidism, due to parathyroid agenesis, has been mapped to a 906-kb region on Xq27 that contains 3 genes (ATP11C, U7snRNA, and SOX3), and analyses have not revealed mutations. We therefore characterized this region by combined analysis of single nucleotide polymorphisms and sequence-tagged sites. This identified a 23- to 25-kb deletion, which did not contain genes. However, DNA fiber–FISH and pulsed-field gel electrophoresis revealed an approximately 340-kb insertion that replaced the deleted fragment. Use of flow-sorted X chromosome–specific libraries and DNA sequence analyses revealed that the telomeric and centromeric breakpoints on X were, respectively, approximately 67 kb downstream of SOX3 and within a repetitive sequence. Use of a monochromosomal somatic cell hybrid panel and metaphase-FISH mapping demonstrated that the insertion originated from 2p25 and contained a segment of the SNTG2 gene that lacked an open reading frame. However, the deletion-insertion [del(X)(q27.1) inv ins (X;2)(q27.1;p25.3)], which represents a novel abnormality causing hypoparathyroidism, could result in a position effect on SOX3 expression. Indeed, SOX3 expression was demonstrated, by in situ hybridization, in the developing parathyroid tissue of mouse embryos between 10.5 and 15.5 days post coitum. Thus, our results indicate a likely new role for SOX3 in the embryonic development of the parathyroid glands

The Society of Vascular and Interventional Neurology (SVIN) Mechanical Thrombectomy Registry: Outcomes in Patients With Acute Ischemic Stroke and COVID‐19

Background Clinical and radiographic outcomes after mechanical thrombectomy in the setting of COVID‐19 infection remain poorly characterized. We sought to determine how COVID‐19 status affects mechanical thrombectomy outcomes in the real‐world setting in the United States. Methods The prospectively maintained multicenter mechanical thrombectomy registry from the Society of Vascular and Interventional Neurology was queried for baseline clinical characteristics among patients with and without COVID‐19 who underwent mechanical thrombectomy between March 1 and December 31, 2020 at 12 sites. Primary outcome was the likelihood of good neurological outcomes (90 day modified Rankin scale 0–2) among patients with COVID‐19 treated with endovascular thrombectomy, which was assessed using multivariable logistic regression adjusted for age, National Institutes of Health Stroke Scale, Alberta Stroke Program Early CT Score, and substantial reperfusion (modified Thrombolysis in Cerebral Infarction 2b, 2c, and 3). Secondary outcomes included National Institutes of Health Stroke Scale at 24 hours. Results Among 915 patients who underwent mechanical thrombectomy during the study period, 51 patients were positive for COVID‐19 (5.6%). Univariate analysis revealed that compared with patients who were COVID‐19 negative, patients who were positive for COVID‐19 were more likely to be male, nonsmokers, have lower Alberta Stroke Program Early CT Score, and present with intracranial internal carotid artery occlusions (Table 1). They were also less likely to achieve successful reperfusion. Multivariable analysis, however, failed to identify any independent associations with COVID‐19 positive status. Conclusion In our cohort, patients postive for COVID‐19 with acute ischemic stroke who undergo mechanical thrombectomy have similar baseline characteristics, imaging features, procedural, and clinical outcomes compared to patients who are negative for COVID‐19 in multivariate analysis. Further analyses are warranted

Aspiration Versus Stent‐Retriever as First‐Line Endovascular Therapy Technique for Primary Medium and Distal Intracranial Occlusions: A Propensity‐Score Matched Multicenter Analysis

Background For acute proximal intracranial artery occlusions, contact aspiration may be more effective than stent‐retriever for first‐line reperfusion therapy. Due to the lack of data regarding medium vessel occlusion thrombectomy, we evaluated outcomes according to first‐line technique in a large, multicenter registry. Methods Imaging, procedural, and clinical outcomes of patients with acute proximal medium vessel occlusions (M2, A1, or P1) or distal medium vessel occlusions (M3, A2, P2, or further) treated at 37 sites in 10 countries were analyzed according to first‐line endovascular technique (stent‐retriever versus aspiration). Multivariable logistic regression and propensity‐score matching were used to estimate the odds of the primary outcome, expanded Thrombolysis in Cerebral Infarction score of 2b–3 (“successful recanalization”), as well as secondary outcomes (first‐pass effect, expanded Thrombolysis in Cerebral Infarction 2c‐3, intracerebral hemorrhage, and 90‐day modified Rankin scale, 90‐day mortality) between treatment groups. Results Of the 440 included patients (44.5% stent‐retriever versus 55.5% aspiration), those treated with stent‐retriever had lower baseline Alberta Stroke Program Early Computed Tomography Scale scores (median 8 versus 9; P<0.01), higher National Institutes of Health Stroke Scale scores (median 13 versus 11; P=0.02), and nonsignificantly fewer medium‐distal occlusions (M3, A2, P2, or other: 17.4% versus 23.8%; P=0.10). Use of a stent‐retriever was associated with 15% lower odds of successful recanalization (odds ratio [OR], 0.85; [95% CI 0.74–0.98]; P=0.02), but this was not significant after multivariable adjustment in the total cohort (adjusted OR, 0.88; [95% CI 0.72–1.09]; P=0.24), or in the propensity‐score matched cohort (n=105 in each group) (adjusted OR, 0.94; [95% CI 0.75–1.18]; P=0.60). There was no significant association between technique and secondary outcomes in the propensity‐score matched adjusted models. Conclusion In this large, diverse, multinational medium vessel occlusion cohort, we found no significant difference in imaging or clinical outcomes with aspiration versus stent‐retriever thrombectomy