Role of Imaging in Evaluating Patients for Cochlear Implantation.

Abstract

Role of Imaging in evaluating patients for Cochlear Implantation. To assess the role of imaging using High resolution computed tomography (HRCT) and Magnetic resonance imaging (MRI) temporal bone for evaluating candidates for cochlear implantation (CI). It was a prospective study conducted in the department of Otorhinolaryngology at a tertiary care centre, 30 children up to 5 years of age with severe to profound sensorineural hearing loss(SNHL) were included in the study, radiological evaluation was done in all children. 20(66.67%) children were in 2-4 years age group with female preponderance. Radiological abnormalities were reported in 13(43.33%) children. Abnormalities of inner ear were seen in 8(26.67%) cases, which included bilateral cochlear nerve aplasia, unilateral cochlear aplasia with bilateral cochlear nerve aplasia, bilateral severe cochlear hypoplasia, mondini's dysplasia. Cochlear nerve deficiency was found in 3(10%) children and narrow Internal auditory canal in 4(13.33%) children. 2(6.67%) patients out of 30 were not the candidates for CI, they had bilateral absent cochlear nerve which is an absolute contraindication for CI. 28(93.33%) patients were evaluated as candidates for CI. Imaging is a fundamental part of the preoperative workup for cochlear implantation, HRCT and MRI temporal bone are complementary to each other in evaluating children for cochlear implantation as HRCT is excellent for demonstrating bony details but, lack in providing details of inner ear neural structures and MRI is better than CT in demonstrating vestibulocochlear nerves.