Abstract

INTRODUCTION- Cholesteatoma is a localized collection of keratinous debris and stratified squamous epithelium. It is located in the middle ear cavity and is very commonly associated with bony erosions of the ossicular chain, facial nerve canal, tegmen tympani, sigmoid plate and other structures of the ear.
AIM- To assess the role of HRCT and MRI in the accurate evaluation of cholesteatoma of middle ear with its histo-pathological correlation.
OBJECTIVES-
1. To study the HRCT findings in diagnosis of cholesteatoma.
2. To determine MRI diffusion restriction in differentiating middle ear focal lesions.
3. To determine the usefulness of these newer diffusion techniques to detect smaller lesions and in postoperative recurrent or residual lesions
4. To correlate the HRCT and MRI evaluation with its HPE findings.
MATERIALS AND METHODS- Our study was carried out in the Department Of Radio-diagnosis, Index medical College Hospital and Research Centre, Indore with 50 subjects.
SEQUENCES USED- Axial, sagittal and coronal views using 128 slice CT scan.
1.5 tesla MRI scanner
RESULTS - The most common clinical features in cholesteatoma is chronic ear discharge seen in 35 (70%), recurrent CSOM in 32 (64%). The least common was facial muscle weakness.
In our study, the Sensitivity to diagnose ossicular chain disruption on HRCT was 100%, specificity was 91.67%. PPV was 97.44% and NPV was 100%.
The Sensitivity of HRCT for diagnosing cholesteatoma was 79.55%, specificity was 66.66%,  PPV 94.59% and NPV was 30.77%
Overall, Sensitivity for diagnosing cholesteatoma on MRI DWI, was 97.73%, specificity was 66.67%,PPV 95.56%. Diagnostic accuracy of DWI was 94%.
CONCLUSION- HRCT is convenient in recognizing erosions of ossicular chain and structures like facial recess, scutum, tegmen tympani etc. DWI MRI is a highly sensitive and efficient modality to precisely detect incidence of novel and recurrent/ residual cholesteatoma in pre and post operative patients respectively.