ATYPICAL HEARING-LOSS IN ACOUSTIC NEUROMA PATIENTS

Audiologic data from 126 patients treated at the University of Califor nia, San Francisco for newly diagnosed acoustic neuromas (ANs) from 19 86 to 1990 were reviewed. Subjectively normal hearing was present in 1 5% of patients and was most frequent in patients with small (<1 cm) tu mors. Only 4% had objectively normal hearing on the basis of speech re ception threshold (SRT), speech discrimination score (SDS), and high-f requency pure-tone loss. This was most frequent in patients with 1 cm tumors. Abnormal but symmetrical hearing is usually not considered to be indicative of a unilateral AN. In the present series, 7% of patient s with ANs possessed symmetrical hearing. High-frequency asymmetry was a more sensitive indicator of the presence of an AN than differences in either SRT or SDS. The clinician must be aware of the relatively hi gh incidence of atypical audiologic findings in acoustic tumor patient s.