title: Microvascular anatomy of the medial temporal region: part 1: its application to arteriovenous malformation surgery.
abstract: BACKGROUND
  The medial temporal region (also called the temporomesial or mediobasal temporal region) is the site of the most complex cortical anatomy.
  
  
  OBJECTIVE
  To investigate the anatomic variability of the arterial supply and venous drainage of each segment of the medial temporal region (MTR), and to discuss and illustrate the implications of the findings for surgery of arteriovenous malformations (AVM) of the MTR.
  
  
  METHODS
  Forty-seven cerebral hemispheres and 10 silicon-injected cadaveric heads were examined using x3 to x40 magnification. Illustrative surgical cases of MTR AVMs were selected.
  
  
  RESULTS
  The anterior choroidal artery (AChA) gave rise to an anterior uncal artery in 83% of hemispheres and a posterior uncal or unco-hippocampal artery in 98%. The plexal segment of the AChA gave off neural branches in 38%. The MCA was the site of origin of anterior uncal, unco-parahippocampal, or anterior parahippocampal arteries in 94% of hemispheres. An anterior uncal artery arose from the internal carotid artery (ICA) in 45% of hemispheres. The posterior cerebral artery (PCA) irrigated the entorhinal area through its anterior parahippocampal or hippocampo-parahippocampal branches in every case. A PCA bifurcation was identified in 89% of hemispheres, typically at the middle segment of the MTR. The most common pattern of bifurcation was by division into posteroinferior temporal and parieto-occipital arterial trunks. The anterior segment of the basal vein had a predominant anterior drainage in 35% of hemispheres, and the middle segment had a predominant inferior drainage in 16%.
  
  
  CONCLUSIONS
  An understanding of the vascular variability of the MTR is essential for accurate microsurgical resection of MTR AVMs.
authors.affiliation: Department of Neurological Surgery, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania, USA.
authors.forename: Juan C
authors.initials: JC
authors.lastname: Fernández-Miranda
authors.forename: Evandro
authors.initials: E
authors.lastname: de Oliveira
authors.forename: Pablo A
authors.initials: PA
authors.lastname: Rubino
authors.forename: Hung Tzu
authors.initials: HT
authors.lastname: Wen
authors.forename: Albert L
authors.initials: AL
authors.lastname: Rhoton
mesh_terms: D001165:Arteriovenous Malformations / Q000473:pathology / Q000601:surgery; D002102:Cadaver; D002536:Cerebral Arteries / Q000033:anatomy & histology*; D006801:Humans; D013702:Temporal Lobe / Q000033:anatomy & histology* / Q000601:surgery