Learning Objectives:

Introduction: Otosclerosis is a treatable cause of hearing loss. However, the clinical diagnosis may be challenged by high-resolution computed tomography (HRCT) of the temporal bone which may demonstrate factors that might alter the expected outcome of surgery. Using a case series of 101 patients with clinically suspected otosclerosis, we demonstrate how HRCT of the temporal bone may be considered the “gold standard” in the pre-operative work-up for otosclerosis patients.

Methods: A retrospective search of our institution's Patient Archive and Communication System for all HRCT scans of temporal bones that were performed for suspected otosclerosis over a five year period (March 2010 - June 2015). The radiological disease pattern was compared to the clinical findings. Alternative diagnoses were recorded.

Results: 101 scans were performed for suspected otosclerosis. Otosclerosis was confirmed in 43 patients, with normal scans reported in 34 cases and alternative diagnoses revealed in 21 patients. A further 3 patients had possible otosclerosis.

Discussion: The diagnostic sensitivity and specificity of HRCT has been reported to be high. HRCT may identify oval window or pericochlear involvement, which may reduce the effectiveness of surgery; it may also demonstrate anatomical factors that may make surgery more challenging.

Conclusion: We believe that HRCT of the temporal bones is an essential tool as part of the work-up of all patients with suspected otosclerosis and that the benefits of this investigation outweigh the risks associated with a modest radiation dose.