Transparahippocampal selective amygdalohippocampectomy in children and adolescents: efficacy of the procedure and cognitive morbidity in patients

Object. Unilateral resection of the hippocampus and amygdala can be used to treat medically intractable mesial temporal lobe seizures. To date seizure outcome and the extent of cognitive morbidity have been unknown in childre n following the transparahippocampal variation of selective amygdalohippoca mpectomy (TSA), which prompted the present prospective study. Methods. Preoperative examinations and outcomes in 22 consecutive children and adolescents who underwent TSA were studied. Cognitive and psychological morbidity were assessed using standard neuropsychological instruments. The authors evaluated relationships between seizure control and cognitive morb idity and 13 and nine clinical variables, respectively. Seizure control was achieved in 11 (65%) of 17 patients (> 2 years follow u p). Among 13 clinical variables, the only preoperative finding that had a s ignificant bearing on seizure control was the presence of unilateral hypome tabolism, which could be observed on [F-18]fluorodeoxyglucose-positron emis sion tomography scans (p < 0.001). Patients with seizure control showed sig nificant improvements in verbal and full scale intelligence quotients (both p = 0.05). Patients with longer preoperative durations of seizures exhibit ed more cognitive impairment that persisted postoperatively. Cognitive outc ome analysis based on nine clinical factors revealed no significant differe nce in cognitive parameters postoperatively, except that significant improv ement occurred in rote verbal memory scores among patients who underwent ri ght-sided TSA (p = 0.01). Individually, 81% of the children achieved signif icant improvement in at least one of seven cognitive parameters, and 52% ha d stable or improved scores in all parameters. Conclusions. The results indicate that TSA is a safe effective approach for the treatment of medically intractable mesial temporal lobe seizures in ch ildren with minimum effect on cognitive morbidity. Given that the literatur e suggests that children suffer progressive cognitive morbidity from persis tent seizures, the results of this study support early surgical interventio n for this group of children.