Arteries of the insula

Object. The insula is located at the base of the sylvian fissure and is a p otential site for pathological processes such as turners and vascular malfo rmations. Knowledge of insular anatomy and vascularization is essential to perform accurate microsurgical procedures in this region. Methods. Arterial vascularization of the insula was studied in 20 human cad aver blains (40 hemispheres). The cerebral arteries were perfused with red latex to enhance their visibility, and they were dissected with the aid of an operating microscope. Arteries supplying the insula numbered an average of 96 (lange 77-112). The ir mean diameter measured 0.23 mm (range 0.1-0.8 mm), and the origin of eac h artery could be traced to the middle cerebral artery (MCA), predominantly the M-2 segment. In 22 hemispheres (55%), one to six insular arteries aros e from the M-1 segment of the MCA and supplied the region of the limen insu lae. In an additional 10 hemispheres (25%), one or two insular arteries aro se from the M-3 segment of the MCA and supplied the region of either the su perior or inferior periinsular sulcus. The insular arteries primarily suppl y the insular cortex, extreme capsule, and, occasionally, the claustrum and external capsule, but not the putamen, globus pallidus, or internal capsul e, which are vascularized by the lateral lenticulostriate: arteries (LLAs). However, an average of 9.9 (range four-14) insular arteries in each hemisp here, mostly in the posterior insular region, were similar to perforating a rteries and some of these supplied the corona radiata. Larger, more promine nt insular arteries (insuloopercular arteries) were also observed (an avera ge of 3.5 per hemisphere, range one-seven). These coursed across the surfac e of the insula and then looped laterally, extending branches to the medial surfaces of the opercula. Conclusions. Complete comprehension of the intricate vascularization patter ns associated with the insula, as well as proficiency in insular anatomy, a n prerequisites to accomplishing appropriate surgical planning and, ultimat ely to completing successful exploration and removal of pathological lesion s in this region.