Imaging prior to endoscopic ear surgery: clinical note

Cholesteatoma is an epidermoid cyst that is characterized by independent and progressive growth with destruction of adjacent tissues, especially the bone tissue, and tendency to recurrence. Treatment of cholesteatoma is essentially surgical. The choice of surgical technique depends on the extension of the disease, and preoperative otoscopic and radiological findings can be decisive in planning the optimal surgical approach. Cholesteatoma confined to the middle ear cavity and its extensions can be eradicated by use of the minimally invasive transmeatal endoscopic approach. Computerized tomography of the temporal bones fails to distinguish a cholesteatoma from the inflammatory tissue, granulations, fibrosis or mucoid secretions in 20-70% of cases showing opacification of the middle ear and mastoid. Using the turbo-spin echo (TSE), also known as non-echo planar imaging (non-EPI) diffusion-weighted (DW) magnetic resonance imaging, cholesteatoma can be distinguished from other tissues and from mucosal reactions in the middle ear and mastoid. Current MRI sequences can support the clinical diagnosis of cholesteatoma and ascertain the extent of the disease more readily than CT scans. The size determined by the TSE/HASTE (half-Fourier acquisition single-shot turbo-spin echo) DW sequences correlated well with intraoperative findings, with error margins lying within 1 mm. Our experience with more than 150 endoscopic surgeries showed that lesions smaller than 8 mm confined to the middle ear and its extension, as depicted by the non-EPI images, can be managed with transmeatal endoscopic approach solely. We call upon our otolaryngologist and radiologist colleagues to use the newest MRI modalities in the preoperative evaluation of candidates for cholesteatoma surgery.