Ganglioneuroma of the Internal Auditory Canal Presenting as a Vestibular Schwannoma

Abstract

In most series, 90% of cerebellopontine angle tumors are vestibular schwannomas. Meningiomas and epidermoid tumors follow with decreased frequency. Ganglioneuroma is a benign tumor usually found in the retroperitoneum and posterior mediastinum. We report a case of a 21-year-old man with gradual sensorineural hearing loss and a minimally enhancing lesion of the internal auditory canal, which was excised through a middle fossa approach and found histologically to be a ganglioneuroma. Like vestibular schwannomas, these lesions are benign in nature and may be managed in a similar fashion, although the possibility of malignant transformation may support surgical resection over conservative management or radiosurgery. Ganglioneuromas should be considered in patients with atypical radiographic findings for vestibular schwannomas.