Objectives/hypothesis: To determine audiometric outcomes and complications of cochlear implantation in patients with enlarged vestibular aqueduct (EVA).
Study design: Retrospective review at a tertiary care children's hospital.
Methods: Twenty-three patients with EVA who underwent cochlear implantation were reviewed using postoperative pure-tone averages (PTA), speech perception thresholds (SPT), Phonetically Balanced Kindergarten test (PBK50) sentence testing scores, and review of complications.
Results: Of the 23 patients, the average age at initial cochlear implant referral was 4.7 years, and the average age at implantation was 5.3 years. EVA was diagnosed by computed tomography (nine patients), magnetic resonance imaging (10 patients), or both (four patients). EVA was identified bilaterally in 19 and unilaterally in four patients. Overall, the mean postoperative PTA was 30.5 dB (+/-8.6 dB standard deviation [SD]), and mean SPT was 25.9 dB (+/-8.1 dB SD). A subset of the patients had postoperative PBK50 sentence testing and the average score was 58% (range, 12%-84%). Four children were implanted within 1 month from entrance into our cochlear implant program (early implanted), and three children were implanted more than 10 months after program entrance (late implanted). The mean postoperative PTA was 40.3 dB (+/-7.6 dB SD) for the early group and 26.3 dB (+/-4.2 dB SD) for the late group. Four patients had reported complications, three had intraoperative cerebrospinal fluid (CSF) gushers at the cochleostomy site, and one had postoperative infection requiring implant removal and reimplantation.
Conclusions: Children with EVA undergoing cochlear implantation are at greater risk for CSF gushers, but they do well audiometrically and functionally.