title: Modified approach for the selective treatment of temporal lobe epilepsy: transsylvian-transcisternal mesial en bloc resection.
abstract: OBJECTIVE
  The authors propose a novel surgical approach for amygdalohippocampectomy (AH) in patients with temporal lobe epilepsy. Via a transsylvian-transcisternal route, the parahippocampal gyrus is directly exposed from its medial aspect, thus allowing a standardized en bloc resection of the temporomesial epileptogenic structures--the amygdala, anterior hippocampus, parahippocampal gyrus, and subiculum. Additional anatomical studies have been performed for standardization of this approach.
  
  
  METHODS
  From 1990 to 1996, 32 patients presenting with medically intractable mesial temporal lobe epilepsy underwent AH via the transsylvian-transcisternal approach. Preoperative computerized tomography and magnetic resonance imaging revealed temporomesial lesions in 16 patients. Histopathological examination revealed cavernous malformations in seven patients, low-grade astrocytomas in four, hamartomas in three, and gangliogliomas in two patients. Specimens obtained in patients with no lesions were diagnosed as hippocampal sclerosis in all cases. No patient experienced permanent morbidity. Nine percent of the patients developed a temporary partial oculomotor nerve palsy. Only one patient developed a postoperative visual field deficit with a contralateral quadrantanopsia. With respect to seizure outcome, all patients benefited from surgery. At follow-up evaluation (mean 26.4 months), 80% of the patients were free from seizures (Engel Class I). Eight patients in this group were no longer receiving medication. Seventeen percent had experienced only one to several seizures since surgery (Engel Class II) and 3% reported a worthwhile improvement (Engel Class III).
  
  
  CONCLUSIONS
  In contrast to previously described standard techniques for AH, the transsylvian-transcisternal approach presented in this study offers improved anatomical orientation and intraoperative control over the mesial temporal lobe and preserves the lateral as well as the laterobasal temporal lobe.
authors.affiliation: Department of Neurosurgery, Klinikum Mannheim, University of Heidelberg, Germany.
authors.forename: P
authors.initials: P
authors.lastname: Vajkoczy
authors.forename: K
authors.initials: K
authors.lastname: Krakow
authors.forename: S
authors.initials: S
authors.lastname: Stodieck
authors.forename: B
authors.initials: B
authors.lastname: Pohlmann-Eden
authors.forename: P
authors.initials: P
authors.lastname: Schmiedek
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000679:Amygdala / Q000601:surgery; D000927:Anticonvulsants / Q000627:therapeutic use; D001254:Astrocytoma / Q000175:diagnosis / Q000000981:diagnostic imaging / Q000473:pathology; D001927:Brain Diseases / Q000175:diagnosis / Q000000981:diagnostic imaging / Q000473:pathology; D001932:Brain Neoplasms / Q000175:diagnosis / Q000000981:diagnostic imaging / Q000473:pathology; D002426:Cavernous Sinus / Q000002:abnormalities / Q000000981:diagnostic imaging / Q000473:pathology; D002946:Cisterna Magna / Q000601:surgery*; D018891:Dentate Gyrus / Q000601:surgery; D018572:Disease-Free Survival; D004833:Epilepsy, Temporal Lobe / Q000175:diagnosis / Q000000981:diagnostic imaging / Q000601:surgery*; D005260:Female; D005500:Follow-Up Studies; D018303:Ganglioglioma / Q000175:diagnosis / Q000000981:diagnostic imaging / Q000473:pathology; D006222:Hamartoma / Q000175:diagnosis / Q000000981:diagnostic imaging / Q000473:pathology; D006423:Hemianopsia / Q000209:etiology; D006624:Hippocampus / Q000601:surgery; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D015840:Oculomotor Nerve Diseases / Q000209:etiology; D011183:Postoperative Complications; D012598:Sclerosis; D013702:Temporal Lobe / Q000000981:diagnostic imaging / Q000473:pathology / Q000601:surgery*; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome; D014786:Vision Disorders / Q000209:etiology; D014794:Visual Fields
chemical_list: D000927:Anticonvulsants