Introduction: Reliable anatomical landmarks are essential to avoiding injuries to the optic tract, anterior choroidal artery and the basal ganglia during anterior temporal lobectomy (ATL). We describe a new anatomic landmark, specifically the Anterior Temporal Sulcus (ATS), as a reliable method to define the anterior portion of the endorhinal sulcus and the superior limit of amygdala resection.
Methods: Twenty-five consecutive patients undergoing anterior temporal lobectomies at Rush University Medical Center (RUMC) were identified and their pre-operative brain magnetic resonance imaging (MRI) studies were analyzed.
Results: The ATS was clearly identifiable on coronal MRI in 48 out of 50 temporal lobes (96%). The ATS was present in all 25 left temporal lobes (100%); two of the 25 right temporal lobes had absent ATS (8%). Following the ATS posteriorly on coronal MRI, it lead to the endorhinal sulcus and accurately predicted the superior extent of in all 25 patients (48 temporal lobes). There is zero incidence of injury to the optic tract, anterior choroidal artery, or basal ganglia using ATS as the landmark for superior limit of amygdala resection.
Conclusions: The ATS is a reliable anatomical landmark that accurately delineates the superior border of the amygdala during anterior temporal lobectomy.
Patient Care: The ATS is a reliable anatomical landmark that accurately delineates the superior border of the amygdala during anterior temporal lobectomy to minimize potential surgical complications.
Learning Objectives: 1) Describe the anatomy of the mesial temporal region
2) Identify the anatomical boundaries for amygdala
3) Identify potential neurovascualr structure that could be injuried during temporal lobectomy.
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