Middle ear opacification on imaging studies performed in a non-traumatic setting mostly reflects chronic inflammatory/infectious disease. In some of these patients an underlying cholesteatoma will be found. High-resolution computed tomography examinations and magnetic resonance imaging are often used in the work-out of the disease. High-resolution computed tomography of the opacified middle ear serves to describe the status of the ossicular chain, and its suspensory apparatus, as well as the status of the tympanic and mastoid wall. When ossicular erosions are visualized, the probability of a present cholesteatoma is about 90%. Whereas high-resolution computed tomography is not able to differentiate cholesteatoma from other types of opacification, magnetic resonance imaging is. The combined use of delayed post-Gd T1-weighted images and non-EPI based DWI seems to be the actual best option on this matter.