Objective and Subjective Improvement of Hearing in Noise After Surgical Correction of Unilateral Congenital Aural Atresia in Pediatric Patients: A Prospective Study Using the Hearing in Noise Test, the Sound-Spatial-Quality Questionnaire, and the Glasgow Benefit Inventory.

OBJECTIVES: The aim of this study was to assess the objective and subjective long-term binaural benefits of surgical correction in children with unilateral congenital aural atresia, using an open-set sentence test in noise and subjective questionnaires.

DESIGN: A prospective study was performed between August 2010 and February 2013. This study included pediatric patients who had unilateral conductive hearing loss (normal bone conduction hearing) on the atretic side but normal air conduction hearing on the normal side and were scheduled to undergo a primary canaloplasty. Pure-tone audiometry, the hearing in noise test (HINT), and questionnaires (Sound-Spatial-Qualities of Hearing Scale; Glasgow Benefit Inventory [GBI]) were administered preoperatively and at 6 and 12 months postoperatively.

RESULTS: Among 34 consecutive patients who initially met enrollment criteria, 26 subjects (23 boys and 3 girls) aged 10 to 16 years (mean 12.3 years) completed this study. Canaloplasty and hearing restoration procedures were performed uneventfully in all patients. The mean air conduction thresholds were significantly improved from 63.9 to 35.0 dB (6 months) and 39.4 dB (12 months) after surgery (p < 0.001). In HINT, speech understanding in noise that was presented toward the newly opened atretic ear significantly improved at 1 year postoperatively (p = 0.014). In noise toward the normal ear, speech understanding significantly improved after surgery, from -0.1 dB preoperatively to -2.0 dB at 6 months (p = 0.002) and -1.8 dB at 12 months (p = 0.005) (p for quadratic trend = 0.036). The composite score improved from -2.6 dB preoperatively to -3.4 dB at 6 months and -3.6 dB at 12 months (p = 0.045; p for linear trend = 0.005). The Sound-Spatial-Qualities of Hearing Scale scores in all domains significantly improved 1 year after surgery (p < 0.034). The mean GBI scores in each domain ranged from 14.2 to 49.4. Total GBI score was correlated with better signal to noise ratio in noise toward the atretic ear as measured by HINT at postoperative 1 year (Spearman ρ = 0.482, p = 0.013).

CONCLUSIONS: Teenaged patients with unilateral congenital aural atresia showed satisfactory hearing improvement after canaloplasty with hearing restoration surgery. In a serial long-term follow-up, speech understanding in noise measured by HINT improved over time. One year after surgery, teenaged children acquired binaural hearing (binaural squelch), as measured by the HINT with noise presented to the newly opened atretic ear. Subjective questionnaires also showed improvements in binaural hearing function and quality of life.