Otosclerosis revision surgery in Sweden: hearing outcome, predictive factors and complications

Purpose To describe the procedures and investigate the hearing outcomes and complications after revision surgery for patients with otosclerosis in Sweden and compare these with previously published reports and to investigate factors that may predict the outcomes of revision surgery. Methods A total of 254 patients from the Swedish Quality Register for otosclerosis surgery who underwent surgery at 21 clinics were identified as having undergone revision surgery for otosclerosis from 2003 to 2013. Clinical records and audio-grams from each of these patients were collected and analyzed. Results Improvement in hearing by 20 dB or more and closure of air-bone gap (<= 20 dB) was achieved in 43% and 69% of patients after a first revision operation and in 46% and 70% of patients after a second revision operation. Most patients who underwent surgery because of dizziness were relieved of their dizziness. Postoperative deafness occurred in 2.3% of patients. Prior successful otosclerosis surgery predicted successful revision surgery, especially after a second revision operation. Fixation of the incus or malleus and finding of no obvious reason for the conductive hearing loss predicted a worse hearing outcome. Conclusions The hearing results after revision surgery in Sweden is somewhat inferior to those of previously published results involving large centers. Postoperative deafness may be as much as fivefold more common after revision surgery than after primary surgery. Meticulous reading of previous charts and honest counseling regarding the risks and expectations is mandatory before planning revision surgery for otosclerosis.