The role of preoperative imaging for auditory implants in children

Abstract

<b>Introduction:</b> Preoperative imaging, besides audiological evaluation, plays a major role in evaluation of candidacy for auditory implants, and in particular cochlear implants. It is essential to assess whether the basic criteria necessary for implantation are met. Diagnostic imaging is crucial not only in determining candidacy, but also determining the feasibility of cochlear implantation as it allow to anticipate surgical difficulties which could preclude or complicate the implantation of the device. The aim of the study is to present the protocol for the evaluation of preoperative imaging studies with particular focus on the factors potentially affecting clinical decisions in children qualified for cochlear implantation. <br><b>Material and method:</b> Preoperative imaging studies of 111 children performed prior to cochlear implantation were analyzed: high-resolution computed tomography (HRCT) of temporal bones and MRI. The assessment was made according to the presented protocol. <br><b>Results:</b> Pathologies and anomalies identified during the assessment of preoperative imaging studies significantly altered clinical decisions in 30% of patients. In the study group, in 17% of patients inner ear malformations were identified. 2.7% of children were disqualified from a cochlear implantation due to severe congenital inner ear malformations. 9% of the patients have had bacterial meningitis. In 50% of them difficulties related to complete or progressive cochlear ossification occurred. In 4.5% of patients less common surgical approaches other than mastoidectomy with a posterior tympanotomy were applied. <br><b>Discussion:</b> Preoperative imaging allow for the identification of significant pathologies and anomalies affecting qualification decisions and further treatment. HRCT and MRI are complementary to each other for preoperative imaging. The two modalities in combination allow accurate and optimal evaluation of the anatomical structures prior to implantation. Inner ear malformations and cochlear ossification following meningitis are relatively frequently encountered in children qualified for a cochlear implant.