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Objective: Outcome in vestibular schwannoma (VS) surgery has improved enormously over the last decades. Surgical positioning remains a matter of discussion. A standardized protocol for diagnostics and management has been applied and evaluated for complications and functional outcome., Methods: We examined 502 VS tumors in 483 patients (227 men and 256 women) between 2005 and 2016. According to our patient selection and treatment algorithm, 488 operations (97%) were performed in the semi-sitting position, and 14 (3%) were in the supine position. Auditory and facial functions were analyzed before and after surgery as were perioperative complications., Results: There were 182 patients (36%) with small tumors (Hannover classification T1-T3A) and 320 (64%) large tumors (T3B or T4). Of the patients, 14% were neurofibromatosis type 2 cases. Complete tumor resection was achieved in 96.4%. Hearing preservation occurred in 44% of patients with small tumors and 23% of those with large tumors (Hannover classification), and correlated significantly with tumor size (P < 0.001). Facial palsy (House Brackmann grades II-VI) was present in 63 patients before and in 185 patients after surgery. Useful facial function (House Brackmann grades I-III) early after surgery was maintained in 86% of patients with small tumors and in 77% of patients with large tumors. Intraoperative complications included air embolism in 45 cases (9%), sinus injury in 3 cases, cerebrospinal fluid leakage in 46 cases (9%), and local hemorrhage in 19 cases (4%). Surgical revision was indicated in 31 cases (6%)., Conclusions: In a standardized setting, the semi-sitting position allowed a safe approach. This setting offers the advantage of bimanual tumor nerve handling by the surgeon and an optimal visualization of important functional structures., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Objective: Deep brain stimulation of the subthalamic nucleus (STN-DBS) is an established treatment for Parkinson's disease (PD). Anatomical connectivity analyses and task-related physiological studies have divided the STN into different functional domains: sensorimotor, limbic, and associative - located in its dorsolateral (dSTN), anteroventral (vSTN) and medial territories, respectively. Targeting sensorimotor STN is essential for stimulation efficacy and is supported by intraoperative micro-electrode recordings. A different neuronal signature in microelectrode recordings across STN subterritories was explored in this study., Methods: Stable recordings from 30 PD patients were assigned to dSTN or vSTN by means of an anatomical method (based on fused computed tomography/magnetic resonance images) and through a priori tri-segmented partition of the recording itself. We computed the inter-spike interval (ISI) and ISI-characteristics, mean firing rate (MFR), discharge patterns and mean burst rate (MBR) of each detected single unit activity., Results: We showed a different MBR between dSTN and vSTN (1.51±0.18 vs. 1.76±0.22events/minute, Wilcoxon rank sum test, p<0.05) and a trend in the difference between their MFR (12.78 vs. 15.05Hz, Wilcoxon rank sum test, p=0.053) only with the anatomically based method., Conclusion: Burst firing differs across STN subterritories., Significance: Different functions of subthalamic domains might be reflected by distinctive burst signalling of its subterritories., (Copyright © 2016 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved.)