Usefulness of High Resolution Computed Tomography scans in depicting the status of the middle ear structures

Background: Prior to surgery it is very important that the surgeon is fully aware, and he should have the clear picture as to the extent of the disease and the nature of the disease to give satisfactory surgical outcomes for the patient. HRCT (High resolution computed tomography) is one such guiding tool for the surgeon. The objective was to study usefulness of HRCT scan in attico-antral disease in depicting the status of the middle ear structures.Methods: A total of 30 patients were studied. HRCT temporal bone was performed by using SIEMENS EMOTION 16 slice CT machine in axial plane and coronal images were reformatted. Findings of HRCT temporal bone were recorded. Findings of mastoid exploration surgery were recorded. Report of HRCT of temporal bone was correlated with surgical findings and tabulated using percentages.Results: Surgery showed cholesteatoma in 26 (86.6%) patients. Epitympanum was involved in 29 (96.6%) patients in HRCT and 30 (100%) patients at surgery. Extension beyond middle ear cleft was seen in 4 (13.3%) patients in HRCT and 5 (16.6%) patients at surgery. Tympanic segment of facial canal was the most commonly involved, showing erosion in 10 (33.3%) patients in HRCT and 12 (40%) patients at surgery. Lateral SCC was the most commonly involved in bony labyrinth seen in 4 (13.3%) patients in both HRCT and surgery. Erosion of dural plate was seen in 6 (20%) patients in HRCT whereas 9 (30%) patients showed dural plate erosion at surgery.Conclusions: HRCT of temporal bone plays a promising role in pre-operative assessment of cholesteatoma as it depicts the extent of the disease and integrity of most of the middle ear structures.