High Prevalence of Moyamoya Syndrome in Appalachia.

INTRODUCTION: Moyamoya is a chronic cerebrovascular condition of unclear etiology characterized by progressive occlusion of 1 or both internal carotid arteries with neovascular collateral formation. With both an idiopathic form (moya-moya disease) and congenital condition-associated form (moyamoya syndrome), it can cause ischemic and hemorrhagic stroke. Recent findings in Kentucky have challenged traditional estimates of its incidence in US populations. Using the Kentucky Appalachian Stroke Registry (KApSR), our aim was to further characterize its incidence as a cause of stroke and to understand the patient population in Appalachia. METHODS: A retrospective review of moyamoya patients was performed using the KApSR database. Data collected included demographics, county location, risk factors, comorbidities, and health-care encounters from January 1, 2012, to December 31, 2016. RESULTS: Sixty-seven patients were identified; 36 (53.7%) resided in Appalachian counties. The cohort accounted for 125 of 6,305 stroke admissions, representing an incidence of 1,983 per 100,000 stroke admissions. Patients presented with ischemic strokes rather than hemorrhagic strokes (odds ratio 5.50, 95% CI: 2.74-11.04, p < 0.01). Eleven patients (16.4%) exhibited autoimmune disorders. Compared to the general population with autoimmune disorder prevalence of 4.5%, the presence of autoimmunity within the cohort was significantly higher (p < 0.01). Compared to non-Appalachian patients, Appalachian patients tended to present with lower frequencies of tobacco use (p = 0.08), diabetes mellitus (p = 0.13), and hypertension (p = 0.16). CONCLUSIONS: Moyamoya accounts for a substantial number of stroke admissions in Kentucky; these patients were more likely to develop an ischemic stroke rather than a hemorrhagic stroke. Autoimmune disorders were more prevalent in moyamoya patients than in the general population. The reduced frequency of traditional stroke risk factors within the Appalachian group suggests an etiology distinct to the population.

Unexpected arteriovenous malformation of the thyroid resulting in significant intraoperative blood loss.

A 49-year-old morbidly obese woman with metastatic endometrial carcinoma was referred for evaluation of an incidentally identified large right thyroid nodule found on computed tomography performed for cancer evaluation. Ultrasound revealed a 9.7 cm solid isoechoic homogeneous right thyroid nodule. Fine needle aspiration was benign. Given size, resection was recommended following completion of chemotherapy and radiation. At the time of right thyroid lobectomy, extremely large vessels were encountered, and the procedure was complicated by estimated blood loss of 2 L. Final pathology revealed a large, benign adenomatous nodule and vascular features consistent with arteriovenous malformation (AVM). Unlike previously reported cases, the diagnosis of a thyroid AVM was not known preoperatively.

Predictive value of platelet reactivity unit (PRU) value for thrombotic and hemorrhagic events during flow diversion procedures: a meta-analysis.

BACKGROUND AND PURPOSE: Platelet function testing prior to flow diversion procedures, although initially heavily debated, has seen a substantial increase in its adoption to assess the risk of operative and perioperative thrombotic and hemorrhagic events. This meta-analysis was conducted to assess platelet function testing, particularly the VerifyNow Platelet Reactivity Unit (PRU) assay, for a relationship between the reported assay PRU value and thrombotic and hemorrhagic events. MATERIALS AND METHODS: The currently available literature (2013-2018) was surveyed with PubMed and Google Scholar searches. Included studies were those for which there were at least 30 cases during the study period, for which VerifyNow platelet reactivity unit values were obtained prior to the procedures and for which intraoperative and perioperative adverse events were noted. PRU value cut-offs ranging from >200 to >240 comprised the hyporesponse group while values ranging from <60 to <70 comprised the hyper-response group. The data were subject to statistical analysis to assess the relationship between PRU values and thrombotic and hemorrhagic events. The collected data were subsequently statistically analyzed to assess for publication bias. RESULTS: The searches yielded 27 studies, of which 12 met the inclusion criteria for the meta-analysis. The meta-analysis included data from 1464 reported Pipeline cases. The study included 273 men and 1177 women with a mean age across the analyzed procedures of 58 years (range 25-85). After loading with antiplatelet medications, preprocedural platelet hyper-responsiveness was associated with a greater incidence of hemorrhagic events with an increased absolute risk of 12%, but showed no relationship with thrombotic events. Preprocedural platelet hyporesponsiveness was associated with a greater incidence of thrombotic events with an absolute risk of 15%, but showed no relationship with hemorrhagic events. CONCLUSIONS: VerifyNow PRU values that correspond to platelet hyporesponse or hyper-response to dual antiplatelet therapy are associated with a higher risk of thrombotic and hemorrhagic events, respectively. Thus, the PRU value may offer some predictive value for these events.