Clinical Characteristics of Vestibular Schwannoma Presenting as Sudden Hearing Loss

Abstract

Background and Objectives : In many cases of vestibular schwannoma (VS), hearing loss is gradually progressive, but some cases of VS show a sudden onset of hearing loss. The purpose of this study is to analyze the incidence of the patients with VS presenting sudden sensorineural hearing loss (SSNHL) among the several chief complaints and to identify their clinical and laboratory characteristics. Patients and Methods :We reviewed retrospectively 87 patients with VS who were diagnosed at the Departments of Otolaryngology, Ajou University Hospital and Yonsei University Hospital from 1994 to 2002. We analyzed chief complaints, size of tumor, pure tone averages (PTA), audiologic studies, caloric tests, imaging studies, and treatment modalities of patients. Results : Eighteen (20.7%) out of 87 patients with VS presented SSNHL as an initial presenting symptom, which was the second most common. The tumor size of patients with SSNHL was small as average 1.4 cm. Their ipsilateral canal paresis was correlated with tumor size, while their PTAs were not. In two out of 18 patients with SSNHL, hearing was recovered partially or completely following steroid therapy. Conclusion : Sudden sensorineural hearing loss can be the first symptom of VS. The patients with unilateral SSNHL, even with recovery, must be evaluated for a possible VS.