Hearing preservation after lateral temporal bone resection for early-stage external auditory canal carcinoma

Abstract

Objective: To evaluate postoperative hearing outcomes after lateral temporal bone resection (LTBR) with reconstruction of the external auditory canal (EAC) and conductive function for early-stage EAC carcinoma.

Methods: We retrospectively examined patients diagnosed with early-stage EAC carcinoma treated with surgery alone between January 2006 and December 2012. Patients who had postoperative adjuvant chemotherapy and/or radiotherapy were excluded. Patients receiving LTBR in combination with tympanoplasty were divided into two groups based on the reconstruction of the EAC with and without (w/o) split-thickness skin grafts (STSGs). Audiological data included the preoperative hearing thresholds and the most recent postoperative hearing thresholds obtained at least 12 months after surgery. The hearing outcome was evaluated based on pure-tone audiograms using the Committee on Hearing and Equilibrium guidelines of the American Academy of Otolaryngology-Head and Neck Surgery for the evaluation of the results of treatment of conductive hearing loss. The postoperative quality of life (QOL) for patients was evaluated using the Glasgow Benefit Inventory (GBI).

Results: All patients (n = 15) achieved disease-free survival without significant morbidity or mortality. When we compared the mean air-bone gaps after surgery, those in the STSG group (n = 8) were found to be significantly lower than those in the w/o STSG group (n = 7; p < 0.001). The success rate for postoperative hearing was 75.0% in the STSG group, which was significantly higher than that in the w/o STSG group (p = 0.014). All patients in the w/o STSG group showed stenosis and closure of the EAC at fewer than 10 months after surgery. In contrast, all patients in the STSG group showed preserved conformation of the new EAC for more than 12 months after surgery. When we compared the mean GBI score between the two groups of patients, the overall and general health scores in the STSG group were found to be significantly higher than those in the w/o STSG group (p = 0.021, p = 0.001).

Conclusions: Reconstruction of the EAC using a rolled-up STSG technique in combination with tympanoplasty after LTBR is useful for hearing preservation and the observation of locoregional lesions after surgery, resulting in improved QOL for patients.