Temporal Lobectomy and Amygdalohippocampectomy Based on Anatomical Landmarks: Operative Anatomy, Surgical Technique and Clinical Outcome
Abstract number :
2.149
Submission category :
Year :
2000
Submission ID :
1237
Source :
www.aesnet.org
Presentation date :
12/2/2000 12:00:00 AM
Published date :
Dec 1, 2000, 06:00 AM
Authors :
Hung T Wen, Carmen L Jorge, Luis H Castro, Kette D Valente, Leticia P Sampaio, Albert L Rhoton, Raul Marino, Univ of Sao Paulo, Sao Paulo, Brazil; Univ of Florida, Gainesville, FL.
RATIONALE: We present the surgical anatomy and the operative technique of the temporal lobectomy and amygdalohippocampectomy, based on anatomical landmarks. To prove its efficacy, we present the preliminary clinical outcome of 32 patients who have been operated on using this technique. METHODS:The surgical anatomy and the operative technique were studied in 52 adult cadaveric hemispheres and 12 adult cadaveric heads, after perfusion of the arteries and veins with colored latex. The clinical outcome was based on the follow up of 32 patients with mesial temporal sclerosis who underwent temporal lobectomy and amygdalohippocampectomy. RESULTS: The surgery consists of neocortical removal, hippocampectomy and amygdalectomy. The neocortical removal is done following the gray matter of the collateral sulcus that points toward the floor of the temporal horn; once the ventricle is opened, the medial disconnection of the hippocampectomy starts with the opening of the choroidal fissure, which separates the fornix from the thalamus, up to the inferior choroidal point, the beginning of the choroidal plexus in the temporal horn,and the contents of the ambient cistern are seen (posterior cerebral artery, basal vein). The medial wall of the temporal horn is then removed "freeing" the head of the hippocampus (anterior disconnection), and the contents of the crural cistern come to the view (peduncle, anterior choroidal artery, basal vein). Finally the tail of the hippocampus is sectioned at the atrium (posterior disconnection) and the tegmentum mesencephalon comes to the view. The amygdala is removed intra or subpially following the carotid artery anteriorly, choroidal fissure posteriorly, optic tract and the inferior choroidal point superiorly. To date 32 patients were operated on, with mean follow up of 23,1 months; 29 (90%) are in Engel I (26 IA, 3 IB), and 3 (10%)are in Engel II. CONCLUSIONS: These vascular and neural structures are landmarks that "guide" surgeons through the temporal lobe. They allow a more precise and extended resection of mesial temporal structures and apparently lead to a better seizure control.