title: Unusual findings in brain biopsies of two patients with acute magnetic resonance imaging lesions associated with focal seizures.
abstract: OBJECTIVE
  Patients with focal seizures often have magnetic resonance imaging (MRI) abnormalities in the brain region of their presumed seizure focus. Neoplasms, ischemic infarctions, inflammatory processes, and other specific pathologic entities have been diagnosed by biopsies of such MRI abnormalities. Two patients with this presentation had brain lesion biopsies with a leading presumptive diagnosis of glial neoplasm but were found to have indistinct histopathology.
  
  
  METHODS
  Each patient was initially seen with focal seizures (right parietal region, right hippocampus) corresponding with focally increased T2 signal on MRI. In both patients, the preoperative clinical suspicion was for neoplastic or inflammatory processes.
  
  
  RESULTS
  Several weeks after seizure onset, craniotomy in patient 1 and stereotactic needle biopsy in patient 2 revealed mild gliosis with reactive vascular changes and perivascular hemosiderin deposition, not diagnostic of but compatible with venous congestion (or possibly venous thrombosis). Postoperatively, patient 1 had brief sensory seizures that stopped 5 months after surgery, whereas subsequent seizures did not develop in patient 2. Both patients had normalization of their MRI (except for postoperative changes) and have remained seizure free.
  
  
  CONCLUSIONS
  We describe two patients who had brain biopsies of striking focal increased T2 signal MRI abnormalities associated with seizures. Pathologic findings contradicted our preoperative suspicions (neoplasm or inflammatory process), compatible with (but not conclusive for) subacute venous congestion/thrombosis. These findings indicate that patients with seizures may have an associated discrete intraaxial MRI lesion that is not neoplastic. To our knowledge, this is the first report of focal seizure-associated MRI lesions with biopsy findings compatible with venous congestion/thrombosis.
authors.affiliation: Department of Neurological Surgery, ColumbiaCollege of Physicians and Surgeons, New York, New York 10032, USA.
authors.forename: Shearwood
authors.initials: S
authors.lastname: McClelland
authors.forename: Jenny M
authors.initials: JM
authors.lastname: Libien
authors.forename: Steven S
authors.initials: SS
authors.lastname: Chin
authors.forename: David J
authors.initials: DJ
authors.lastname: Adams
authors.forename: Stanley R
authors.initials: SR
authors.lastname: Resor
authors.forename: Stephen
authors.initials: S
authors.lastname: Chan
authors.forename: Robert R
authors.initials: RR
authors.lastname: Goodman
mesh_terms: D000328:Adult; D001707:Biopsy, Needle; D001921:Brain / Q000473:pathology*; D001927:Brain Diseases / Q000473:pathology / Q000601:surgery; D003399:Craniotomy; D004828:Epilepsies, Partial / Q000473:pathology* / Q000601:surgery; D005260:Female; D005911:Gliosis / Q000473:pathology; D006486:Hemosiderosis / Q000473:pathology; D006624:Hippocampus / Q000473:pathology; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000706:statistics & numerical data*; D008297:Male; D008875:Middle Aged; D011300:Preoperative Care; D013238:Stereotaxic Techniques; D016896:Treatment Outcome; D020246:Venous Thrombosis / Q000473:pathology