TY - JOUR T1 - The Insula: Anatomic Study and MR Imaging Display at 1.5 T JF - American Journal of Neuroradiology JO - Am. J. Neuroradiol. SP - 222 LP - 232 VL - 25 IS - 2 AU - Thomas P. Naidich AU - Eugene Kang AU - Girish M. Fatterpekar AU - Bradley N. Delman AU - S. Humayun Gultekin AU - David Wolfe AU - Orlando Ortiz AU - Indra Yousry AU - Martin Weismann AU - Tarek A. Yousry Y1 - 2004/02/01 UR - http://www.ajnr.org/content/25/2/222.abstract N2 - BACKGROUND AND PURPOSE: The insula is important for gustatory sensation, motor speech control, vestibular function, and sympathetic control of cardiovascular tone. The purpose of this study was to test two hypotheses: 1) gross anatomic study of the insula will disclose reproducible patterns of insular structure, and 2) analysis of MR appearance will enable physicians to recognize these patterns on imaging studies.METHODS: Gross insular anatomy was determined in 16 normal human cadaveric hemispheres. The 1.5-T MR images of 300 insulae were analyzed to determine the gyral and sulcal patterns displayed; their relationship to the Heschl gyrus, to the overlying opercula, and to the vertical planes perpendicular to the Talairach-Tournoux baseline at the anterior commissure (VAC) and posterior commissure (VPC); their continuity into the orbitofrontal cortex; and appropriate landmarks for the anterior border, apex, and posterior border of the insula.RESULTS: MR images displayed the central sulcus of the insula (97%); the anterior (99%), middle (78%), and posterior (98%) short insular gyri that converge to the apex (100%) anteriorly; and the anterior (99%) and posterior (58%) long insular gyri posteriorly. The middle short gyrus was often hypoplastic (33%). The anterior intersections of the internal and external capsules typically delimit the anterior insular border (87%). VAC intersects the anterior insula (99%), usually at the precentral sulcus. The Heschl gyrus circumscribes the posteroinferior insula (100%). VPC demarcates the posterior insular border (94%).CONCLUSION: The two hypotheses were proved correct. The insula shows reproducible patterns of gross anatomy that are demonstrable on routine clinical MR images obtained at 1.5 T. ER -