CNS ORAL PRESENTATIONS stage, family history, and coexistent with cerebral aneurysms were not associated with any increased risk of rebleeding. CONCLUSION: Rebleeding events were common in patients with hemorrhagic MMD and the risk of rebleeding increased within a very long-term follow-up. Rebleeding was strongly associated with increased mortality. Decrease of rCBF, smoking, and drinking history seem to be risk factors for rebleeding. 105 Decreases in Blood Pressure During Endovascular Stroke Therapy Are Common and Associated With Poor Functional Outcome David Mampre; Anson Wang; Kevin Sheth; Can Ozan Tan; Ryan M. Hebert, MD; Charles C. Matouk,BSc, MD; Nils Petersen INTRODUCTION: Due to impaired cerebral autoregulation, blood pressure management during acute ischemic stroke is critical for avoiding secondary neurological injury and poor outcomes. However, questions concerning optimal management of blood pressure (BP) levels during endovascular therapy (EVT) remain unanswered. This study sought to examine the effect of reductions in BP and sustained hypotension during EVT on functional outcome. METHODS: We prospectively enrolled patients with acute large- vessel occlusion ischemic stroke undergoing EVT at Yale-New Haven Hospital. Intraprocedural SBP was monitored using a noninvasive BP cuff or an intra-arterial catheter. ? SBP was calculated as the difference between admission SBP and lowest SBP during EVT. Sustained relative hypotension was measured as the area between admission SBP and continuous measurements of intraprocedural SBP (aSBP). Associations with functional outcome assessed using the modified Rankin Scale (mRS) at discharge and 90 d (unfavorable outcome = 3) were assessed using ordinal and binary logistic regression. RESULTS: One hundred-twenty patients (mean age 72 ± 14, 69 F, mean NIHSS 18) were included in the study, 79 of which had 90- d outcomes. Mean admission SBP was 153 mm Hg. 92% of patients experienced ? SBP reductions during EVT (mean 46 ± 30 mm Hg). Median ? SBP among patients with favorable outcomes was 28 mm Hg (IQR 5-53) compared to 49 mm Hg (IQR 18-71) among patients with poor outcome. ? SBP was independently associated with higher (worse) mRS scores at discharge (P = .004) and at 90 d (P = .014) after adjusting for age, gender, and admission NIHSS. Every 10 mm Hg reduction in SBP from admission during EVT was associated with a 1.22-fold increase in the odds of having an unfavorable functional outcome at 90 d. The association between aSBP and outcome was also significant at discharge (P = .008) and 90 d (P = .014). CONCLUSION: Blood pressure reductions during EVT are common and lead to worse functional outcomes for patients affected by large-vessel acute ischemic stroke. 106 Sacrificing the Superior Petrosal Vein During Microvascular Decompression Does Not Increase Vascular Complications: Experience From One Institution Yuanxuan Xia, BA; Timothy Y. Kim, BS; Leila A. Mashouf BS; Kisha K. Patel; Risheng Xu, AB, AM, MD, PhD; Joshua Casaos BS; Eileen Kim; Alice L. Hung, BA; Adela Wu Sc.B., A.B.; Tomas Garzon-Muvdi, MD, MS; Matthew T. Bender, MD; Christopher M. Jackson, MD; Chetan Bettegowda, MD, PhD; Michael Lim, MD INTRODUCTION: Microvascular decompression (MVD) is an established procedure for treating conditions such as trigeminal neuralgia and hemifacial spasm. However, during a standard retrosigmoid approach, the decision to sacrifice the superior petrosal vein (SPV) is controversial. There have been multiple reports of complications including life-threatening brainstem infarction and cerebellar edema. This study analyzes the potential for vascular complications when the SPV is sacrificed during an MVD. METHODS: Retrospective chart review was performed to identify all MVDs from 2007 to 2018 by the senior author. Cases with >1 mo of follow-up were included and sacrifice of the SPV or its branches was noted. The primary outcome was complications related to SPV sacrifice including sinus thrombosis, cerebellar edema, and midbrain or pontine infarction. Imaging was used to confirm all potential vascular complica- tions mentioned in clinical notes. Fisher’s exact test and unpaired t-tests were used to compare between groups. RESULTS: A total of 701 MVD cases were identified and 570 met inclusion criteria with an average follow-up of 12.0 ± 16.7 mo and a male-to-female ratio of 1:2.1. A total of 141 patients (24.7%) had previous interventions and 10 patients had previous ipsilateral MVDs. The SPV was sacrificed in 211 cases and retained in 359 cases. At final follow-up, 149 patients (70.6%) were pain-free in the group with the sacrificed vein and 240 patients (66.9%) were pain-free in the nonsac- rificed group (P = .402). No SPV-related vascular complications were found in this study. Two unrelated cases of vascular complications were identified and both were in the nonsacrificed group. One case involved cerebellar bleeding while the other was an ipsilateral transverse sinus thrombosis that was present preoperatively. CONCLUSION: In MVDs, there is no difference in rate of vascular complications when the SPV is sacrificed compared to preserved. To best visualize a cranial nerve and optimize safe decompression, surgeons should feel free to resect the SPV. 107 Prospective Randomized Study Comparing Clinical, Functional, Aesthetic and Quality of Life Results of Transpalpebral, Nanopterional, and Classic Pterional Approaches Mauricio Mandel, MD, PhD; Rafael Tutihashi, MD, PhD; Eberval G. Figueiredo, MD, PhD; Jefferson R. Junior; Brasil Jeng; Manoel J. Teixeira INTRODUCTION: Minimally invasive neurosurgery is already a reality in many centers across the world. However, the real role of these techniques and their effect on the outcome of patients is still obscure. METHODS: A total of 111 adult patients with unruptured anterior circulation aneurysms were randomized and underwent a minimally invasive surgical approach (36 by transpalpebral approach and 34 through a reduced minipterional craniotomy) or classical pterional approach (41 patients). Patients in the study group were subjected to a specific protocol for assessment of early hospital discharge. Surgical, clinical/functional, and aesthetic outcomes were evaluated along with long-term quality of life. 82 | VOLUME 65 | NUMBER 1 | SEPTEMBER 2018 www.neurosurgery-online.com Downloaded from https://academic.oup.com/neurosurgery/article-abstract/65/CN_suppl_1/82/5074848 by guest on 24 May 2020