RADT-33. INTRATUMORAL HEMORRHAGE IN VESTIBULAR SCHWANNOMAS FOLLOWING GAMMA KNIFE STEREOTACTIC RADIOSURGERY

Abstract

Abstract INTRODUCTION Intratumoral hemorrhage (ITH) is a rare occurrence in vestibular schwannomas (VS) resulting in worsening vestibular and cranial nerve deficits. Scarce data described the occurrence, management, and outcomes of ITH after stereotactic radiosurgery (SRS). OBJECTIVE The aim of this study is to delineate the incidence, presentation, management, and outcomes of ITH in VS patients following SRS. METHODS A total of 2058 patients with VS underwent Gamma Knife radiosurgery (GKRS) at the University of Pittsburgh Medical Center between 1987 and 2022. The authors identified patients with ITH. Their presentation, management, clinical, and imaging outcomes are reported and analyzed. RESULTS A total of 1902 VS patients had sufficient clinical and imaging follow-up data. Five Koos III (n = 1) and IV (n = 4) VS patients developed ITH after GKRS, resulting in a cumulative incidence rate of 0.26%. The age at presentation ranged from 62 to 79 years, and 3 of the patients were males. The time from VS diagnosis to GKRS ranged from 1-13 months, and the time from GKRS to ITH ranged from 2-130 months. Three patients had bleeding risk factors. One patient required urgent surgical intervention due to the ITH volume, while the other four patients initially were observed. Three remained stable and required no delayed intervention. Histopathological analysis revealed multiple fragments of S-100–positive cells, hemorrhage, and hemosiderin-laden macrophages. At last follow-up, 4 patients had clinically improved, and one remained stable.ConclusionVS ITH following SRS is a rare complication with a cumulative incidence rate of 0.26%. Patient-tailored management is vital based on patient presentation, acuity, and ITH size and characteristics.