AUDIOVESTIBULAR RESULTS AFTER SURGERY FOR CEREBELLOPONTINE ANGLE MENINGIOMAS

Meningiomas are the second most common cerebellopontine angle (CPA) tu mor. The reported rates of hearing preservation following surgical rem oval vary between 32% and 100%. There is only one recent report discus sing vestibular function after CPA meningioma removal. In this series of 31 patients with CPA meningiomas, 16 patients had their tumors remo ved via the retrosigmoid approach. All 16 had audiovestibular assessme nt pre- and postsurgery and were the subjects of this study. Class A h earing is socially useful hearing and is defined as a pure tone averag e (PTA; average of 500 Hz and 1, 2 and 4 kHz) of <30 dB and speech des crimination scores (SDS) of >70%. Class B hearing is serviceable heari ng, defined as PTA of <50 dB and SDS of >50%. Nine patients had class A hearing, and two had class B hearing presurgery. Socially useful hea ring was preserved in six of nine (67%) patients in whom it was presen t before surgery, and serviceable or better hearing was preserved in e ight of 11 (73%). Vestibular symptomatology and examination findings i mproved despite a decrease in the number of patients with intact calor ic function postsurgery. Patients who retained vestibular function on caloric testing were symptomatically better than those who lost calori c function. These results confirm that excellent audiovestibular funct ion is possible after CPA meningioma surgery.