Computed tomography and magnetic resonance imaging in pediatric unilateral and asymmetric sensorineural hearing loss

Objective: To compare temporal bone computed tomography (CT) with temporal bone and central nervous system magnetic resonance (MR) imaging in children with unilateral or asymmetric sensorineural hearing loss (SNHL). Design: Retrospective chart study. Setting: Tertiary-care children's hospital Patients: A total of 131 children with unilateral or asymmetric SNHL, seen consecutively by a single practitioner over 36 months. Intervention: Imaging studies were read by a pediatric neuroradiologist and reviewed by the evaluating otolaryngologist. Main Outcome Measure: Prevalence of clinically significant CT or MR imaging findings. Results: The prevalence of CT abnormalities was 35% for unilateral SNHL, 52% for asymmetric SNHL, and 41% for all patients together. The prevalence of MR imaging abnormalities was 25% for unilateral SNHL, 50% for asymmetric SNHL, and 30% for all patients together. Among 42 subjects who underwent both studies, there were 4 cases in which abnormalities were seen only on MR images and 9 cases in which abnormalities were seen only on CT scans. Conclusions: Temporal bone and/or central nervous system abnormalities were detected in 42% of 131 patients. When both CT scans and MR images were obtained (n = 42), results were concordant in 69% of cases, and one imaging modality detected clinically significant abnormalities not identified by the other in 31% of cases. The ideal imaging algorithm for children with unilateral or asymmetric SNHL is controversial. We suggest that all children with unilateral or asymmetric SNHL have a high-resolution temporal bone CT scan and that brain and temporal bone MR imaging be obtained in select cases.