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Petrous Bone Cholesteatoma Removal With Hearing Preservation

Objective: Clinical and radiologic outcome analysis after petrous bone cholesteatoma (PBC) removal with simultaneous functional reconstruction. Study Design: Retrospective case review over an observation period of 16 years (1992-2007). Setting: Tertiary referral center. Patients: A total of 21 patients (17 adults and 4 children) with PBCs were included, accounting for 3.4% of all cholesteatoma cases (n = 621). The average follow-up duration was 7 years (range, 2-15 yr). In all patients, a modified subtotal petrosectomy was performed with simultaneous tympanoplasty, musculoplasty, and meatoplasty in 90%. In 2 patients (10%), the cavity was obliterated. Two others (10%) needed a simultaneous temporal craniotomy. Main Outcome Measures: Preoperative, intraoperative, and postoperative findings including signs, classifications, recurrences, hearing, and facial nerve outcomes. Results: In the majority of patients (67%), a supralabyrinthine PBC was found. Complete macroscopic resection was achieved in all patients. During the follow-up period, 4 patients (19%) were identified as having recurrent disease. Hearing was postoperatively preserved in 14 of 17 patients with preoperative hearing (82%; 4 preoperative dead ears), of whom, 13 had functional hearing, with a mean pure-tone average of 37 dB (range, 15-55 dB). Preoperative facial nerve dysfunction completely resolved in 4 of 6 patients, and no new dysfunctions occurred postoperatively. All cavities became self-cleaning and dry. Conclusion: Hearing preservation was feasible in the majority of patients with PBCs. The functional surgical concept and the high number of supralabyrinthine lesions seemed to be important prerequisites for the good functional outcomes observed.