title: Correlation of MRI and histopathology in epileptogenic parietal and occipital lobe lesions.
abstract: BACKGROUND
  To analyze the diagnostic accuracy of MRI in patients undergoing parietal and occipital lobe epilepsy surgery.
  
  
  METHODS
  In a retrospective study, we analyzed MRI scans and neuropathology reports of 42 patients who had undergone resective epilepsy surgery in the parietal and occipital lobe between 1998 and 2003. We evaluated, whether lesions were precisely characterized by MRI and whether lesion characterization allowed to estimate postsurgical seizure outcome.
  
  
  RESULTS
  Within the categories epilepsy associated tumors, focal cortical dysplasias, vascular malformations, scarring, and others, MRI was concordant with histopathology in 36 of 42 (86%) lesions. Among the discordant lesions, one lesion was re-classified following MRI-histopathology synopsis, another two lesions represented new tumor entities (angiocentric neuroepithelial tumor, isomorphic astrocytoma) which have been described recently. Seizure freedom (Engel class I) one year following surgery was achieved in 25 patients (60%). Seizure outcome was different for lesion categories (Engel class I: epilepsy associated tumors, 62%; focal cortical dysplasias, 71%; vascular malformations, 75%; scarring, 40%), and was unchanged if no lesion was found on preoperative MRI.
  
  
  CONCLUSIONS
  If MRI and histopathology are discordant, not only the MRI findings may be debatable. MRI lesion detection is important, since chance of seizure freedom is low if no lesion is detected.
authors.affiliation: Department of Radiology, University of Bonn Medical Center, Bonn, Germany. urbach@uni-bonn.de
authors.forename: Horst
authors.initials: H
authors.lastname: Urbach
authors.forename: Devin
authors.initials: D
authors.lastname: Binder
authors.forename: Marec
authors.initials: M
authors.lastname: von Lehe
authors.forename: Martin
authors.initials: M
authors.lastname: Podlogar
authors.forename: Christian G
authors.initials: CG
authors.lastname: Bien
authors.forename: Albert
authors.initials: A
authors.lastname: Becker
authors.forename: Johannes
authors.initials: J
authors.lastname: Schramm
authors.forename: Thomas
authors.initials: T
authors.lastname: Kral
authors.forename: Hans
authors.initials: H
authors.lastname: Clusmann
mesh_terms: D000293:Adolescent; D000328:Adult; D001932:Brain Neoplasms / Q000150:complications / Q000473:pathology; D004569:Electroencephalography; D004827:Epilepsy / Q000473:pathology* / Q000601:surgery; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D002538:Intracranial Arteriovenous Malformations / Q000150:complications / Q000473:pathology; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D019635:Neurosurgical Procedures; D009778:Occipital Lobe / Q000473:pathology* / Q000601:surgery; D010296:Parietal Lobe / Q000473:pathology* / Q000601:surgery; D011446:Prospective Studies; D015899:Tomography, Emission-Computed, Single-Photon; D016896:Treatment Outcome