Neurotological Manifestations of fourth Ventricle Tumors

Abstract

Objective: The area of the fourth ventricle is particularly difficult to evaluate owing to its relatively small size and unique shape. However, this area encompasses many vital structures including the brainstem as its floor, and the cerebellum as its lateral wall and roof. Therefore, a fourth ventricle tumor presents some vital neurotological manifestations. Five cases of fourth ventricle tumors that occurred over the past 8 years are presented herein. Patients and Methods: From January 1991 to December 1998, a total of 9694 patients with vertigo/dizziness received a battery of audiological and neurotological tests. Forty-five (0.4%) cases were diagnosed as having brain tumors, five of which were in the fourth ventricle. Results: The five tumors included one epidermoid cyst, one ependymoma, one astrocytoma, one cavernous angioma, and one metastatic breast breast cancer. In addition to dizziness, other symptoms included ataxia in four cases, vertigo in three, tinnitus in three, and vomiting, hearing loss, headache in two cases, respectively. Four cases displayed abnormal nystagmus. The prognosis was poor, and four cases passed away within 2 years. Conclusions: A fourth ventricle tumor should be considered, when a patient displays ataxia, persistent vomiting, and central nystagmus, such as bilateral gaze nystagmus, downbeat nystagmus, or persitent unilateral nystagmus.