Participants
Eight subjects (16 ears, 4F4M, average age 21.88 years old) whose pure tone audiometry (PTA) thresholds were less than 25 dB HL at each frequency from 250 Hz to 8 kHz (average PTA of 0.5/1/2/4kHz was 4.38±4.96) were enrolled to undergo fs-ABR in SPC and OR to standardize the system. Forty-two CHL subjects who were determined to take ossiculoplasty in our hospital were enrolled from 2016 to 2019 whose etiologies were listed in the Supplemental table1. Four hearing tests were required: the pre-operative and 3 to 6-month post-surgery PTA tests in SPC; pre-operative fs-ABR test under general anesthesia before the surgery in OR; intra-operative fs-ABR test right after the reconstruction with recovered external canal skin flap.