Is HRCT Temporal Bone Necessary in All Cases of Active Squamous Chronic Otitis Media?

Abstract

To assess the usefulness of high resolution computed tomography (HRCT) temporal bones in cases of active squamous chronic otitis media (COM). Comparison of HRCT findings with operative findings. A prospective study of 104 clinically diagnosed patients with COM were included. Each patient was subjected to full clinical evaluation and HRCT temporal bone was done. Preoperative HRCT finding were correlated with surgical findings. The sensitivity of HRCT temporal bone in detecting cholesteatoma was 91.81%. However it could not differentiate cholesteatoma from other soft tissue density like granulation or hypertrophic mucosa or discharge, but soft tissue attenuation content with bone erosion was considered as hallmark of cholesteatoma. The sensitivity and specificity of HRCT for detecting malleus, incus and stapes erosion was 71.5 and 88.5%, 86.3 and 95% and 53.1 and 64.7% respectively. The sensitivity and specificity for detecting erosion of lateral semicircular canal (LSCC) was 77.78 and 98.2%. The sensitivity and specificity for facial canal was 80 and 100%. HRCT gives excellent details about the extent of cholesteatoma with reasonable accuracy in expert hands. It helps to warn the surgeon about anatomical variations preoperatively and detects complications if any. It effectively depicts integrity or erosion of dural plate, sinus plate, LSCC, facial nerve. Malleus and incus are seen reasonably well but status of stapes are not recorded effectively.