Neuropsychological outcome following minimal access subtemporal selective amygdalohippocampectomy

PURPOSE The present study provides a detailed account of neurocognitive outcome following minimal access subtemporal selective amygdalohippocampectomy (SAH) and establishes rates of neurocognitive decline in the largest sample to date. Use of a subtemporal surgical approach to SAH has been proposed to possibly reduce the risk for postoperative neurocognitive decline since lateral neocortical tissues is not resected and the temporal stem is preserved. The current study extends prior research with subtemporal SAH patients to include not only group level analyses but also analyses based on reliable change data. METHODS Neurocognitive comparisons are made between 47 patients that underwent subtemporal SAH. Statistical comparisons were made between neurocognitive performance at the group level and with use of reliable change scores. RESULTS Approximately 75% of patients were seizure free postoperatively. At the group level, there were no significant postoperative changes. For the left SAH patients, reliable change scores demonstrated a decline in approximately one third of patients for memory, verbal intellect, and naming. Right SAH patients showed decline primarily in memory. CONCLUSIONS These results indicated good seizure control following subtemporal SAH with greatest risk for neurocognitive decline following dominant SAH and best cognitive outcome following non-dominant SAH. Findings demonstrated the importance of reliable change analyses that make individual based comparisons and take into account measurement error. Despite preservation of the lateral neocortical tissue and the temporal stem, subtemporal SAH presents a risk for cognitive decline in a notable portion of patients.