OBJECTIVE: To analyze and compare the clinical application of alternating click evoked electrocochleography (ECochG) and auditory brainstem response (ABR) in the diagnosis of auditory neuropathy (AN) subjects. METHOD: ECochGs and ABRs were recorded in 16 patients (32 ears) with AN/AD as AN group and 20 patients (26 ears) with sensorineural hearing loss(SNHL) as control group. Test stimuli were alternating polarity clicks. (1) To compare the occurrence rate of ECochGs and ABRs in AN patients. (2) To compare the peak latency of CAPs, absolute amplitude of CAPs, and amplitude ratios of -SP and CAP between AN group and control group. RESULT: ECochGs (--SPs or CAPs) presented in 78.1% (25 among 32 ears) of AN patients. CAPs latency of AN group was shorter than control group (P < 0.05), CAP absolute amplitude of AN group was lower than normal group (P < 0.05), while --SP/CAP was higher than control group (P < 0.01). Deformed ABRs presented in only 5 ears among 32 tested AN ears, while relative good ABR waveforms were evoked in control group. The occurrence rate of ABRs (15.6%) was significantly lower than that of ECochGs in AN patients (P < 0.01). CONCLUSION Both ECochGs and ABRs play important role in the diagnosis of AN. The capacity of temporal processing is significantly impaired while the intensity perception related capability is intact in AN patients.
Adolescent ; Adult ; Audiometry, Evoked Response ; Auditory Threshold ; Case-Control Studies ; Evoked Potentials, Auditory, Brain Stem ; Hearing Loss, Central ; diagnosis ; physiopathology ; Hearing Tests ; Humans ; Middle Aged ; Young Adult