[Gd-DTPA-enhanced MR imaging of cholesteatoma]

It is sometimes difficult to differentiate a cholesteatoma from an accompanying cholesterol granuloma, mucosa, fluid and, especially, granulation tissue. This study was designed to assess the reliability with which cholesteatoma can be differentiated from such accompanying lesions by Gd-DTPA-enhanced MR imaging. Twenty-one patients with cholesteatoma were studied with magnetic resonance (MR) imaging. The cholesteatoma had intermediate to high signal intensities similar to those of granulation tissue, on both T1- and T2-weighted images. On Gd-enhanced images, however, there was marked enhancement of all granulation tissues while the cholesteatoma showed no such enhancement. Gd-DTPA-enhanced images distinguished cholesteatoma from granulation tissues and permitted determination of the exact extent of the cholesteatoma. Cholesterol granulomas showed high signal intensities on both T1- and T2-weighted images. Cholesterol granuloma can, therefore, be distinguished from cholesteatoma and granulation tissues on both T1- and T2-weighted images. Gd-DTPA-enhanced MR imaging is a valuable tool in the evaluation and management of cholesteatoma.