Study On Surgical Outcomes And Prognostic Factors Of Refractory Temporal Lobe Epilepsy Based On Stereotactic-electroencephalogram

Objective:We would like to separately count the efficacy of radiofrequency thermocoagulation and surgical resection in patients with refractory temporal lobe epilepsy who underwent preoperative evaluation with SEEG,and to analyze the prognostic influences of both,and finally to compare the differences in prognostic influences between the two treatment modalities.Methods:The clinical data of patients with refractory temporal lobe epilepsy who underwent surgical evaluation with intracranially placed SEEG in the Department of Functional Neurosurgery at the Second Hospital of Lanzhou University were retrospectively collected from January 2018 to June 2022,and patients were followed up by telephone or outpatient visits to collect data on patient prognosis and complications,use Engel’s classification of postoperative outcome to assess prognosis,The prognosis of patients undergoing SEEG-guided radiofrequency thermocoagulation and surgical resection of the epileptogenic zone were counted over time,and the factors affecting the prognosis of these two treatment modalities were analyzed.Finally,explain the differential factors affecting the prognosis of these two modalities.Results:We collected clinical data of 36 patients with refractory temporal lobe epilepsy evaluated by SEEG,of whom 23 patients underwent SEEG-guided radiofrequency thermocoagulation and 20 patients underwent surgical resection of the epileptogenic zone after evaluation.We analyzed the prognosis of patients with both treatment modalities and found that the efficacy of surgical resection of the epileptogenic zone was better than that of SEEG-guided radiofrequency thermocoagulation,and the efficacy of both treatment modalities decreased with time extension,but the efficacy of patients with radiofrequency thermocoagulation decreased more rapidly.Twenty-three patients who underwent radiofrequency thermocoagulation to destroy the epileptogenic zone were followed up for 2-36 months,and by the time of the final follow-up 7 patients(30.4%)with Engel 1,2 patients(8.7%)with Engel Ⅱ,9 patients(39.1%)with Engel Ⅲ,and 5 patients(21.7%)with Engel ⅣStatistical analysis of factors that may affect prognosis revealed five factors associated with a good prognosis for radiofrequency thermocoagulation:short duration of epilepsy(P=0.001),MRI finding of limited lesions(P=0.019),PET-CT finding of unifocal hypometabolic areas(P=0.02.),location of the epileptogenic area in the nondominant hemisphere(P=0.001),and disappearance of intracranial epileptiform discharges after thermocoagulation(P=0.004).Twenty patients who underwent surgical resection of the epileptogenic zone were followed up for 6-59 months,and by the time of the final follow-up 11 patients(55.0%)with Engel Ⅰ,6 patients(30.0%)with Engel Ⅱ,3 patients(15.0%)with Engel Ⅲ,and no patients with Engel Ⅳ Statistical analysis of factors that may affect prognosis revealed that MRI findings of limited lesions(P=0.022),PETCT findings of unifocal hypometabolic areas(P=0.028),and the absence of abnormal electrocorticography discharges after lesion excision(P=0.017)were associated with a good prognosis of surgical resection.When comparing the differences in prognostic factors between the two treatment modalities,it was found that there were differences in the prognostic impact of the epileptic course and the relationship between the epileptogenic zone and the dominant hemisphere.The difference in the prognostic impact of the epileptic course is mainly due to the fact that the extent of damage by thermocoagulation is much smaller than that by surgical resection,and the difference in the prognostic impact of the relationship between epileptogenic zone and dominant hemisphere is mainly from the selection bias of the surgical patients.Conclusion:(1)Surgical resection of the epileptogenic zone was more effective than SEEG-guided radiofrequency thermocoagulation,and the efficacy of surgical resection of the epileptogenic zone was more stable than another one;(2)The five factors of short duration of epilepsy,MRI finding of a limited lesion,PET-CT finding of a unifocal hypometabolic zone,epileptogenic zone located in the nondominant hemisphere,and disappearance of intracranial epileptiform discharges after thermocoagulation were associated with good prognosis of SEEG-guided RF-TC;(3)MRI finding of a limited lesion,PET-CT finding of a unifocal hypometabolic zone,and absence of abnormal electrocorticography discharges after lesion excision were associated with good prognosis for resection of the epileptogenic zone.