title: Individual variations in the sulcal anatomy of the basal temporal lobe and its relevance for epilepsy surgery: an anatomical study performed using magnetic resonance imaging.
abstract: OBJECTIVE
  The concept of selective amygdalohippocampectomy is based on pathophysiological insights into the epileptogenicity of the hippocampal region and the definition of the clinical syndrome of mesial temporal lobe epilepsy (TLE). High-resolution magnetic resonance (MR) imaging allows correlation of the site of histologically conspicuous tissue with anatomical structure. The highly variable sulcal pattern of the basal temporal lobe, however, definitely complicates the morphometric analysis of histomorphologically defined subdivisions of the hippocampal region. The goal of this study was to define individual variations in the sulcal anatomy on the basis of preoperative MR images obtained in patients suffering from TLE.
  
  
  METHODS
  The authors analyzed coronal MR images obtained in 50 patients for the presence of and intrinsic relationships among the rhinal, collateral, and occipitotemporal sulci. The surface relief of consecutive sections of 100 temporal lobes was graphically outlined and the resulting maps were used for visual analysis. The sulci were characterized by measurement of their depth, distance to the temporal horn, and laterality. The anatomical measurements and frequencies of sulcal patterns were assessed for statistical correlation with patients' histories and the lateralization of the seizure focus.
  
  
  CONCLUSIONS
  Statistical assessment shows that patient sex is a significant factor in sulcal patterns. Anatomical measurements are significantly decreased on the side of the seizure origin, which relates to loss of white matter, a known morphological abnormality associated with TLE. Magnetic resonance imaging allows for accurate preoperative knowledge of individual sulcal patterns and facilitates intraoperative orientation to anatomical landmarks.
authors.affiliation: Department of Neurosurgery, University of Vienna Medical School, Austria. klaus.novak@akh-wien.ac.at
authors.forename: Klaus
authors.initials: K
authors.lastname: Novak
authors.forename: Thomas
authors.initials: T
authors.lastname: Czech
authors.forename: Daniela
authors.initials: D
authors.lastname: Prayer
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Dietrich
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Serles
authors.forename: Stephan
authors.initials: S
authors.lastname: Lehr
authors.forename: Christoph
authors.initials: C
authors.lastname: Baumgartner
mesh_terms: D000293:Adolescent; D000328:Adult; D000679:Amygdala / Q000473:pathology / Q000601:surgery*; D002648:Child; D002675:Child, Preschool; D003399:Craniotomy; D004292:Dominance, Cerebral / Q000502:physiology; D004833:Epilepsy, Temporal Lobe / Q000473:pathology / Q000601:surgery*; D005260:Female; D006624:Hippocampus / Q000473:pathology / Q000601:surgery*; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D012016:Reference Values; D013238:Stereotaxic Techniques; D013702:Temporal Lobe / Q000473:pathology / Q000601:surgery*