Authors :
Presenting Author: Yuta Tanoue, PhD – Osaka Metropolitan University
Takehiro Uda, PhD – Lecturer, Neurosurgery, Osaka Metropolitan University; Yuichiro Kojima, MD – Neurosurgery – Osaka Metropolitan University; Vich Yindeedej, MD – Neurosurgery – Osaka Metropolitan University; Saya Koh, MD – Neurosurgery – Osaka Metropolitan University; Toshiyuki Kawashima, MD, PhD – Neurosurgery – Osaka Metropolitan University; Takeo Goto, PhD – Professor, Neurosurgery, Osaka Metropolitan University
Rationale:
Stereotactic electroencephalography (SEEG) has been increasingly used for the intracranial evaluation of focal epilepsy. The advantage of SEEG is its less invasiveness compared with subdural electrode, which requires a big craniotomy. Along this line with less invasiveness, if the seizure focus is determined as locally situated by SEEG, subsequent epilepsy surgery should be less invasive as possible. Here, we report our case series of the use of neuroendoscope aiming for less invasiveness after SEEG.
Methods:
Eighteen patients who underwent epilepsy surgery after diagnosis by SEEG from January 2019 to April 2023 were retrospectively reviewed. Information regarding tentative diagnosis by noninvasive examination, etiology, site and number of electrodes implanted, surgical procedure, and seizure outcome were collected. These data were compared between neuroendoscopic and microscopic surgery to search the appropriate situation for the use of neuroendoscope.
Results:
The tentative diagnoses were frontal lobe epilepsy in nine patients and temporal lobe epilepsy in nine patients. Eight patients had unilateral SEEG implantation, and the other 10 patients had bilateral implantation. The mean number of implanted electrodes was 6.3. The etiologies were hippocampal sclerosis in four patients, posttraumatic ulegyria, post limbic encephalitis, focal cortical dysplasia, cavernous hemangioma, and periventricular heterotopias in one patient each. Remaining nine patients had no obvious histological abnormalities. Neuroendoscopic surgery was performed in eight patients for selective amygdalohippocampectomy (n=4), hippocampal transection (n=1), resection of cavernous hemangioma (n=1), and cortical resection (n=2). The seizure outcomes in these eight patients were Engel Class 1 in seven, and Class 3 in one at the last visit. Microscopic surgery was performed in 10 patients for cortical resection at frontal lobe (n=4), frontal lobectomy (n=3), temporal lobectomy (n=1), amygdalohippocampectomy (n=1), hippocampal transection (n=1). The seizure outcomes in these 10 patients were Class 1 in five, Class 2 in three, and Class 3 in two.
Conclusions:
The advantage of the use of endoscope is its ability of approaching deep lesions from a narrow space and obtaining a wide operative view. It might be efficiently applied for selective amygdalohippocampectomy and focal resection at deep part of the brain. In addition, for surface procedures such as cortical resection and lobar disconnection, the efficacy of the use of neuroendoscope might be less.
Funding: None