[Diagnostic value of high frequency oscillation in localization of type â ¡ focal cortical dysplasia epilepsy].

Retrospective analysis was conducted on 9 patients with type Ⅱ focal cortical dysplasia (FCD) who underwent stereo-electroencephalography (SEEG) implantation in the Department of Neurosurgery of the First Affiliated Hospital of Fujian Medical University from November 2020 to February 2023. The onset area, onset time, and frequency of high-frequency oscillations (HFO) were analyzed and the correlation of HFOs with interictal, preictal, and ictal periods. SEEG recordings of 80-500 Hz HFOs were observed in both interictal and ictal periods in 9 patients, with 6 patients exhibiting fast ripples (FR) in the range of 250-500 Hz. Surgical resection of the seizure onset area and FR-generating electrodes was performed, and postoperative follow-up for over 2 years indicated Engel I in 5 cases. 6 patients showed continuous discharge during the preictal period, and the distribution index of continuous discharge was positively correlated with seizure frequency. HFOs in the range of 80-500 Hz were present in all four seizure onset patterns during the ictal period. The onset area and FR-emitting electrode were surgically removed in 6 patients with continuous discharge and overlapping HFOs during the preictal period, with 5 cases of Engel I. Type Ⅱ FCD discharges exhibited complexity, high discharge indices, and a close association with HFOs. Compared with the spike wave, the electrode range of HF is more limited, and the incidence of HF before attack is significantly increased, which is closely correlated with the onset area. The simultaneous occurrence of HFO and the spike waves has higher diagnostic value than the individual occurrence, effectively enhancing surgical efficacy.

[Postoperative outcomes and influencing factors of diffuse low-grade glioma-related epilepsy].

The clinical and pathological features and postoperative outcomes of 49 patients with diffuse low-grade glioma -related epilepsy who were admitted to the Department of Neurosurgery of the First Affiliated Hospital of Fujian Medical University from January 2015 to December 2018 were analyzed. After 1-year follow-up, 33 patients (67.3%) in the good prognosis group and 16 patients (32.7%) in the poor prognosis group were enrolled. Multivariate logistic regression analysis indicatedthat subtotal tumor resection (OR=5.56, 95%CI:1.21-25.44,P=0.027) and no postoperative radiotherapy (OR=9.24, 95%CI:2.05-41.75, P=0.004) were the risk factors for poor prognosis of postoperative epilepsy. Therefore, for patients with diffuse low-grade glioma-related epilepsy, total tumor resection and postoperative radiotherapy are beneficial to the control of epilepsy.

[Clinicopathologic characteristics and causes of difficulty in locating the "difficult to locate" intractable epilepsy].

Objective: To summarize the clinicopathological characteristics of "difficult to locate" intractable epilepsy patients, and investigate the causes of difficulty in their location. Method: Retrospective analysis was performed on the clinical data of 58 patients who underwent resection of the epileptogenic zones after intracranial electroencephalography (iEEG) detection at the Department of Neurosurgery of the First Affiliated Hospital of Fujian Medical University from January 2010 to December 2018. Clinicopathological characteristics and lesion lobes of "difficult to locate" intractable epilepsy were summarized. The prognosis of patients was assessed according to Engel grading.Univariate and multivariate logistic regression analysis were used to investigate the relevant factors affecting the prognosis of patients with "difficult to locate" intractable epilepsy related to malformation of cortical development(MCD). Results: Among the 58 patients, there were 47 cases of MCD (12 cases with mild malformation of cortical development (mMCD), 35 cases with focal cortical dysplasia (FCD)), and 11 cases of other types. Among the 47 MCD cases, univariate analysis showed that patients with preoperative magnetic resonance imaging(MRI) positive and completed resection of the epileptogenic zones had better prognosis (P<0.05). Multivariate analysis indicated that completed resection of epileptogenic zones was an independent factor affecting the postoperative efficacy of MCD (P=0.013,Wald χ(2)=6.149, 95%CI: 0.07-0.56). And among the 47 MCD cases, 18 cases were with mono-lobar lesions and 29 cases were with multi-lobar lesions, however, there was no significant difference of the efficacy between the two groups (P=0.511). Conclusions: MCD, especially FCD, is the main pathological types of patients with "difficult to locate" intractable epilepsy. Multi-lobar pathological changes, especially multi-lobar MCD, are the main reasons of being difficult to locate, however, accurate locating of epileptogenic zones and functional areas via effective use of iEEG can achieve satisfactory efficacy in these patients after resection of the epileptogenic zones.