The Value of High Resolution Computed Tomography in Detecting the Causes of Conductive Hearing Loss

Abstract

INTRODUCTION: The purpose of this study is to evaluate the efficacy of high resolution computed tomography (HRCT) in assessing middle ear ossicular pathologies in cases with normal eardrum who underwent diagnostic tympanotomy due to conductive hearing loss. METHODS: In this study, temporal bone HRCT images of 80 patients with normal eardrum who underwent middle ear exploration due to conductive type hearing loss were evaluated retrospectively. Pathologic findings and anatomic variations of middle ear and ossicular structures were determined. These findings were compared with the intraoperative findings of the patients. RESULTS: The most common operative diagnosis, stapedial otosclerosis was;35 (43%), and deterioration of the integrity of the incudostapedial joint due to the incus long-arm defect was;25 (31%). As of the other pathologies, erode incus and stapes was detected in 14 patients (17%), and tympanosclerosis-related malleus incus fixation was detected in 6 patients (7%). Sensitivity for HRCT for these pathologies was determined 85% for otosclerosis, 88% for incus long-arm defect, 92% for erode-incus and stapes, and 66% for malleus incus fixation. DISCUSSION AND CONCLUSION: Temporal bone HRCT is an effective and easily applicable imaging method with high sensitivity in detecting the cause of conductive hearing loss in patients with normal eardrums.

Keywords

• conductive hearing loss
• high resolution computed tomography
• otosclerosis.