Abstracts

Rationale:
To evaluate early and late naming outcome according to the resection status of the Basal Temporal Language Area (BTLA) identified by cortical stimulations during Stereo-Electro-Encephalography (SEEG).
Method:
Twenty patients who underwent SEEG for drug-resistant temporal lobe epilepsy met the inclusion criteria. During language mapping, a site was considered positive when stimulation of 2 contiguous contacts elicited at least one naming impairment during 2 remote sessions. After temporal lobe resection (TLR) ipsilateral to their BTLA, patients were classified as BTLA+ when at least one positive language-site was resected and as BTLA- when positive language sites were preserved. Outcomes in naming and verbal fluency tests were assessed using pre- postoperative (mean 7 and 25 months after surgery) scores at the group level and reliable change indices for clinically meaningful changes at individual level.
Results:
BTLA+ patients (n=7) had significant worse naming scores compared to BTLA- (n=13) patients within one-year after surgery but not at the long-term evaluation. No difference in verbal fluency tests was observed. When RCI was used, 5 patients out of 18 (28%) had naming decline within one-year postoperatively (corresponding to 57% of BTLA+ and 9% of BTLA- patients). A significant correlation was found between resection of the BTLA and this naming decline.
Conclusion:
Resection of the BTLA is associated with a specific and early naming decline. Even if this decline is transient, BTLA+ patients tend to keep lower naming scores compared to their baseline. SEEG mapping helps to predict postoperative language outcome after dominant TLR.
Funding:
:None