Objective: To examine the anatomy of the basal temporal and the occipital surface, and analyze the variations associated with the sulcus and gyri characteristics. Material and methods: Fifth formalin-fixed human brain hemispheres were observed on its basal temporal and occipital surface and the morphology of the collateral and occipitotemporal sulcus and fusiform gyrus were analyzed. Results: Collateral and occipitotemporal sulcus were present in 50 (100%) hemispheres. Only 15 (30%) had a continuous collateral sulcus with the occipitotemporal sulcus. So, the fusiform gyrus was well identified in only 15 (30%) specimens. Only 14 (28%) had a symmetric anatomy. Conclusion: Fusiform gyrus is well defined when the collateral and occipitotemporal sulcus are continuous. This study showed that the well defined fusiform gyrus was only 30% of the specimens, although the collateral and occipitotemporal sulcus were present in all of the hemispheres.102133136Rhoton Jr., A.L., Tentorial Incisura (2000) Neurosurgery, 47 (SUPPL. 1), pp. S131-S153Wen, H.T., Rhoton Jr., A.L., Basic neuroanatomy A Textbook of Neurointensive Care, , Layon AJ, Gabrielli A, Friedman WA (eds.). Philadelphia: W.B. Sauders Co. (In Press)Wen, H.T., Rhoton Jr., A.L., De Oliveira, E.P., Cardoso, A.C., Tedeschi, H., Baccanelli, M., Marino Jr., R., Microsurgical anatomy of the temporal lobe (1999) Neurosurgery, 45, pp. 549-592Wen, H.T., Rhoton Jr., A.L., De Oliveira, E.P., Transchoroidal approach of third ventricle: Choroidal an anatomic study of fissure and its clinical application (1998) Neurosurgery, 42, pp. 1205-1219Yasargil, M.G., Wieser, H.G., Selective amygdalohippocampectomy at the University Hospital, Zurich (1987) Surgical Treatment of the Epilepsies, pp. 653-658. , Engel J Jr (ed.). New York: Raven PressNagata, S., Rhoton Jr., A.L., Barry, M., Microsurgical anatomy of the choroidal fissure (1988) Surg Neurol, 30, pp. 3-59