The high resolution modification of an EMI 5005 scanner was utilized with an edge enhancement technique to study inflammatory lesions of the temporal bone. Bone erosions caused by cholesteatomas can be accurately delineated because of the circumscribed nature of expansion. The soft tissue masses cannot be appreciated by present CT techniques. Erosions of the horizontal semicircular canal and involvement of the sinus tympani are readily visualized by CT scanning. Computed tomography is limited in demonstrating the stapes superstructure and horizontal portion of the facial canal due to the inability to obtain good coronal scans. The remaining ossicles can be demonstrated with equal clarity with pluridirectional tomography.