Neurotology, Part IMagnetic Resonance Imaging of the Internal Auditory CanalValvassori, Galdino E. M.D; Palacios, Enrique M.DAuthor Information From the Departments of Radiology and Otolaryngology, University of Illinois at Chicago Medical Center, Chicago, Illinois, U.S.A. (G.E.V.) and the Department of Radiology, University of Louisiana (E.P.), New Orleans, Louisiana, U.S.A. Address correspondence and reprint requests to Dr. Galdino E. Valvassori, Departments of Radiology and Otolaryngology, University of Illinois at Chicago Medical Center, 1740 W. Taylor Street, m/c 931, Chicago, IL 60612, U.S.A. Topics in Magnetic Resonance Imaging: February 2000 - Volume 11 - Issue 1 - p 52-65 Buy Abstract Magnetic resonance imaging (MRI) is presently the study of choice for assessment of the internal auditory canal (IAC). MRI provides excellent assessment of the IAC and the bony changes occurring in the canal walls, and it provides excellent demonstration of the content of the canal. Pathological processes arising within the IAC are well visualized by various MR sequences. The possibility of demonstrating masses as small as 2 mm has propelled MRI into the leading role for diagnosis of vestibular schwannoma. Unfortunately, the high cost of MR has been a limiting factor in its use as a screening test for patients with sensorineural hearing loss (SNHL) of unknown origin. Auditory brain stem response has been widely used as a screening procedure, but this test fails to recognize small lesions and cannot be used whenever hearing loss is severe. In this article, we will discuss our approach to assessment of the IAC in patients with retrocochlear SNHL or vestibular symptoms of central origin, review the pathological processes involving the IAC walls or arising within the canal, emphasizing the appropriate MRI sequences used for diagnosis. © 2000 Lippincott Williams & Wilkins, Inc.