The role of imaging in the diagnosis and management of otosclerosis.

OBJECTIVE: To examine the evidence for the role of radiologic imaging in the diagnosis and management of otosclerosis. DATA SOURCES: A review of contemporary (1990 to present) English medical literature via MedLine using the terms imaging, otosclerosis, otospongiosis, stapes surgery, computed tomography, magnetic resonance, CT, and MRI was performed. STUDY SELECTION: Abstracts were reviewed independently by 2 authors and relevant articles were then evaluated. Exclusion criteria included editorials, non-English language, comments, and letters. DATA EXTRACTION: Level of evidence was assigned in accordance with the Oxford Centre for Evidence-based Medicine guidance (Levels I-V). RESULTS: Thirty-seven articles met the inclusion criteria, of which, 11 were of Level III, 22 of Level IV, and 4 of level V evidence. High-resolution computed tomography (CT) of the temporal bones is the imaging technique of choice in the diagnosis of otosclerosis with newer multidetector scanners demonstrating a sensitivity and specificity in excess of 90%. There is Level III evidence that CT densitometry and extent of disease on CT correlates with hearing thresholds. Extensive and multifocal disease on CT has a poorer prognosis (Level III/IV). The potential use of CT in staging classifications, surgical planning, predicting surgical outcomes and risk of complications has also been described and evaluated. CONCLUSION: This systematic review indicates that imaging has a useful role in both the diagnosis and management of otosclerosis, supported principally by Level III/IV evidence.