Early post-laser stapedotomy heating thresholds

Objective: Auditory testing is not routinely performed within 4-6 weeks after stapedotomy, because hearing acuity is thought to be transiently depressed. In rare circumstances, postsurgical auditory and vestibular complaints may lead one to test hearing soon after stapedotomy. The early postoperative effects of carbon dioxide (CO₂) and potassium titanyl phosphate (KTP) lasers, which now are routinely used to perform stapedotomies, have not been reported. The purpose of this report is to present normative data for auditory thresholds measured within 2 weeks of laser stapedotomy. Study Design: The study design was a prospective, unblinded study. Setting: The study was conducted at three academic medical centers. Patients: Thirty-six subjects undergoing 38 stapedotomies for otosclerosis by 5 surgeons participated. Main Outcome Measures: Behavioral audiometry was performed using standard techniques beginning before surgery and continuing through >1 year after surgery. Results: The CO₂ laser was used in 26 stapedotomies and the KTP laser was used in 12. Nine cases were revision procedures. Bone conduction pure-tone averages and speech discrimination scores did not worsen during the early postoperative period. Bone conduction at 250 and 4,000 Hz dropped slightly within the first 2 weeks (-4.3 and -6.7 dB) but recovered thereafter. Bone conduction at 1,000 Hz actually improved within the first week after surgery (+6.2 dB, p = 0.021). Significant improvements in air conduction thresholds (and air-bone gap) were seen at the second week and late audiometry. The results for CO₂ and KTP laser-treated groups were not significantly different. Conclusions: Cochlear function is not significantly depressed in the early postoperative period after laser (CO₂ or KTP) stapedotomy.