Left Cerebral Hemisphere After Removing the Cortical Gray Matter and the Adjacent Short U Fibers. A, Left cerebral hemisphere after removing the cortical gray matter and the adjacent short U fibers of the frontoparietal and temporal operculum, middle and inferior frontal gyri (F2 and F3) and middle and inferior temporal gyri (T2 and T3). 1, Horizontal segment of the superior longitudinal fasciculus (SLF II); 2, SLF arcuate segment; 3, U fibers; 4, SLF corresponding to the radiation to the parietal gyri; 5, corona radiata; 6, anterior short insular gyri; 7, posterior long insular gyri; 8, anterior transverse gyrus of Heschl; 9, posterior insular point; arrows, SLF arching around the outer edges of the insula. B, Next step in white matter dissection, after removing the arcuate and temporal segments of the SLF. 1, SLF horizontal segment (SLFII); 2, occipital segment of the stratum sagittale; 3, temporal segment of the stratum sagittale; 4, anterior short insular gyri; 5, posterior long insular gyri; 6, limen insulae; 7, superior limitant sulcus of the insula; 8, inferior limitant sulcus of the insula; 9, posteromedial part of pars orbitalis; 10, posterior insular point; arrows, stratum sagittale. C, Next step in dissection, after removing the gray matter from insular short and long gyri. 1, Limen insulae; 2, superior limitant sulcus of the insula; 3, inferior limitant sulcus of the insula; 4, extreme capsule; 5, fibers showing corona radiata under U fibers; 6, stratum sagittale. D, Another view of the same step shown in C. 1, Extreme capsule; 2, corona radiata; 3, intermingling between external capsule and corona radiata; 4, inferior fronto-occipital fasciculus (IFOF); 5, stratum sagittale; 6, medial orbital gyrus; 7, gyrus rectus. (Images courtesy of E de Oliveira)