ABR absolute latencies and interpeak intervals were reviewed for 684 non-tumor ears and 75 eighth-nerve tumor ears having various degrees of high frequency hearing loss. For non-tumor ears, the percentage of abnormal absolute latencies for waves I, III, and V increased rather systematically as hearing loss increased, whereas absolute latencies for eighth-nerve tumor ears were largely abnormal regardless of hearing loss. Interpeak intervals were normal for most of the non-tumor ears, but the I–III and I–V intervals were abnormal for most of the tumor ears. The most sensitive index for otoneurologic assessment was a combination of abnormal wave V interaural latency differences or I–V interpeak interval, and the most specific criterion was the I–V interpeak interval. Tumor size influenced sensitivity of most ABR indices.
Clinical Results of the Modified Canalith Repositioning Maneuver