Learning Objectives: CTandMRimaging are complementary imaging options. Simultaneous dual modality imaging has no additional diagnostic value over sequential diagnostics. We therefore propose a stepwise radiological workup.

Introduction: To evaluate the clinically relevant abnormalities as visualized on CT and MR imaging in children with unilateral sensorineural hearing loss (USNHL), and the association with age and severity of hearing loss.

Methods: From January 2006 until January 2016, a total of 102 children diagnosed with USNHL were included in this study. They underwent CT and/or MR imaging for the evaluation of the etiology of their hearing loss.

Results: Causative abnormalities were identified in 49% of the children with USNHL. Overall, deformities of the labyrinth were the most prevalent abnormality (30%), predominantly identified by CT (20%). MR imaging outperformed CT regarding abnormalities of the cochlear nerve (7 vs. 2 %) and the brain (7 vs. 0 %). In cases where both imaging modalities were performed, concordant CT and MR imaging findings were found in 75 %. No differences in the number and type of abnormalities were found in the different grades of hearing loss or age categories.

Conclusion: Imaging is essential in the etiologic diagnosis of USNHL because of the high prevalence of causative abnormalities that can be identified, irrespective of the patients’ age or degree of hearing loss.