Prediction of Hearing Preservation in Vestibular Schwannoma Surgery According to Tumor Size and Anatomic Extension

• Published in: Otolaryngology-head and neck surgery 2022-03, Vol.166 (3), p.530-536
• Main Authors: Bozhkov, Yavor, Shawarba, Julia, Feulner, Julian, Winter, Fabian, Rampp, Stefan, Hoppe, Ullrich, Doerfler, Arnd, Iro, Heinrich, Buchfelder, Michael, Roessler, Karl
• Format: Article
• Language: English
• Subjects: Erlangen vestibula schwannoma grading; grading systems; Hearing; hearing preservation; Humans; Koos vestibular schwannoma grading; Neuroma, Acoustic - pathology; Neuroma, Acoustic - surgery; Radiosurgery; Retrospective Studies; Treatment Outcome; vestibular schwannoma surgery
• ISSN: 0194-5998; 1097-6817
• DOI: 10.1177/01945998211012674

Objective Vestibular schwannoma (VS) surgery is feasible for various tumor sizes that are inappropriate for wait and scan or radiosurgery. The predictive value of 2 grading systems was investigated for postoperative hearing preservation (HP) in a large series. Study Design Retrospective analysis. Setting Neurosurgical patient database of the University of Erlangen was queried between 2014 and 2017. Methods Retrospective single-center analysis on 138 VSs operated on via a retrosigmoidal approach. The mean tumor size was 20.4 mm (SD, 7.6 mm) with fundal infiltration in 67.4%. The overall resection rate was 93.5%. Tumors were classified preoperatively by the 3-tier Erlangen grading system depending on size or the anatomically based 4-tier Koos grading system. Results Preoperative hearing preservation was found in 70.3% of patients and was significantly correlated to tumor size (P = .001). For Erlangen grading, a mean postoperative serviceable hearing preservation rate of 32% was achieved: 83.3% for tumors 25 mm. In contrast, according to Koos grading, postoperative serviceable hearing preservation was 100% for grade 1 tumors (meatal), 35.6% for grade 2 (cisternal), 23.1% for grade 3 (brainstem contact), and 21.7% for grade 4 (brainstem compression). Of the total cohort, 86% had normal or nearly normal postoperative facial function (House-Brackmann grades 1 and 2). Conclusion Surgery on small VSs can achieve excellent hearing preservation. Different grading has a significant influence on and correlates with postoperative hearing preservation. Tumor size seems more important than anatomic relationship.