Neuropsychological outcome following minimal access subtemporal selective amygdalohippocampectomy

Abstract

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.

Neuropsychological outcomes of subtemporal selective amygdalohippocampectomy via a small craniotomy

“…In recent studies it was found that approximately one-third of patients who underwent SAH on the left side of the brain had loss of memory, verbal intellect, and naming, whereas patients who had surgery on the right side of the brain mainly had loss of visual memory. 2,3 Our results seem to confirm the findings of previous studies in which loss of verbal memory was reported after surgery on the dominant side of the brain; however, we cannot determine whether it is due to any disruption of unknown functional networks of mesial temporal lobe structures. Further studies are warranted to clarify these results.…”

Neuropsychological outcome after selective amygdalohippocampectomy: subtemporal versus transsylvian approach

“…Thus subtemporal patients displayed a considerably (up to sixfold) increased risk of decline in visual/figural learning compared with transsylvian operated patients. Similar negative effects of subtemporal SAH on figural memory after left and right surgery have been obtained in a recent prospective but uncontrolled study on cognitive outcome of a large sample of 53 patients using the BVMT-R (Brief Visual Spatial Memory Test-Revised) with reliability of change indices for determination of individual change 43. While systematic changes in memory after temporal lobe surgery have mainly be described for verbal memory after left temporal resection, this is the first time that in two independent studies a negative effect of temporal lobe surgery on visual/figural memory is evident.…”

Stereotactic EEG-guided laser interstitial thermal therapy for mesial temporal lobe epilepsy

“…Dominant hemispheric resection is often associated with cognitive declines in naming and verbal learning, while non-dominant hemispheric resection is associated with impaired nonverbal memory, object recognition and figural learning 37. SAH may provide better neurocognitive outcomes than ATL 38.…”