Is intraoperative electrocorticography (ECoG) for long-term epilepsy-associated tumors (LEATs) more useful in children?-A Randomized Controlled Trial.

OBJECTIVES: The utility of intraoperative electrocorticography (ECoG)-guided resective surgery for pediatric long-term epilepsy-associated tumors (LEATs) with antiseizure medication (ASM) resistant epilepsy is not supported by robust evidence. As epilepsy networks and their ramifications are different in children from those in adults, the impact of intraoperative ECoG-based tailored resections in predicting prognosis and influencing outcomes may also differ. We evaluated this hypothesis by comparing the outcomes of resections with and without the use of ECoG in children and adults by a randomized study. METHODS: From June 2020 to January 2022, 42 patients (17 children and 25 adults) with LEATs and antiseizure medication (ASM)-resistant epilepsy were randomly assigned to one of the 2 groups (ECoG or no ECoG), prior to surgical resection. The 'no ECoG' arm underwent gross total lesion resection (GTR) without ECoG guidance and the ECoG arm underwent GTR with ECoG guidance and further additional tailored resections, as necessary. Factors evaluated were tumor location, size, lateralization, seizure duration, preoperative antiepileptic drug therapy, pre- and postresection ECoG patterns and tumor histology. Postoperative Engel score and adverse event rates were compared in the pediatric and adult groups of both arms. Eloquent cortex lesions and re-explorations were excluded to avoid confounders. RESULTS: Forty-two patients were included in the study of which 17 patients were in the pediatric cohort (age < 18 years) and 25 in the adult cohort. The mean age in the pediatric group was 11.11 years (SD 4.72) and in the adult group was 29.56 years (SD 9.29). The mean duration of epilepsy was 9.7 years (SD 4.8) in the pediatric group and 10.96 (SD 8.8) in the adult group. The ECoG arm of LEAT resections had 23 patients (9 children and 14 adults) and the non-ECoG arm had 19 patients (8 children and 11 adults). Three children and 3 adults from the ECoG group further underwent ECoG-guided tailored resections (average 1.33 additional tailored resections/per patient.).The histology of the tailored resection specimen was unremarkable in 3/6 (50%).Overall, the commonest histology in both groups was ganglioglioma and the temporal lobe, the commonest site of the lesion. 88.23% of pediatric cases (n = 15/17) had an excellent outcome (Engel Ia) following resection, compared to 84% of adult cases (n = 21/25) at a mean duration of follow-up of 25.76 months in children and 26.72 months in adults (p = 0.405).There was no significant difference in seizure outcomes between the ECoG and no ECoG groups both in children and adults, respectively (p > 0.05). Additional tailored resection did not offer any seizure outcome benefit when compared to the non-tailored resections. CONCLUSIONS: The use of intraoperative electrocorticography in LEATs did not contribute to postoperative seizure outcome benefit in children and adults. No additional advantage or utility was offered by ECoG in children when compared to its use in adults. ECoG-guided additional tailored resections did not offer any additional seizure outcome benefit both in children and adults.

Atypical teratoid rhabdoid tumour in the third ventricle of a young adult - a rare presentation.

INTRODUCTION: Atypical teratoid/rhabdoid tumours (AT/RT) are malignant CNS tumours predominantly seen in infants and children. Adult AT/RTs have a predilection for mid-line structures, such as the pineal and pituitary glands. We report a case of AT/RT in a young adult, with its origin from the third ventricle. This is the first documented case of adult AT/RT in the third ventricle. CASE PRESENTATION: A 20-year-old male presented with acute onset headache and vomiting. MRI showed a lesion involving the optic chiasm, hypointense on T1, and heterogeneously hyperintense on T2, with stippled post-contrast enhancement. He underwent a right peri-coronal parasagittal craniotomy, transforaminal and sub choroidal approach with gross total tumour resection. Histopathological report was ATRT, WHO grade 4, with loss of SMARCB1 (INI1) protein. He later underwent a ventriculo-peritoneal shunt placement for postoperative hydrocephalus and was later given adjuvant chemoradiotherapy. No recurrence was noted on follow up MRI. CONCLUSION: AT/RTs are not limited to the paediatric age group, and their incidence among adults is being increasingly reported. Occurrence of AT/RT in the third ventricle of a young adult male has never been reported in the past. It merits consideration as a differential diagnosis of any midline lesion with malignant appearance in adults.

Extracellular vesicles in glioblastoma: a challenge and an opportunity.

Glioblastoma is a highly heterogeneous tumor whose pathophysiological complexities dictate both the diagnosis of disease severity as well as response to therapy. Conventional diagnostic tools and standard treatment regimens have only managed to achieve limited success in the management of patients suspected of glioblastoma. Extracellular vesicles are an emerging liquid biopsy tool that has shown great promise in resolving the limitations presented by the heterogeneous nature of glioblastoma. Here we discuss the contrasting yet interdependent dual role of extracellular vesicles as communication agents that contribute to the progression of glioblastoma by creating a heterogeneous microenvironment and as a liquid biopsy tool providing an opportunity to accurately identify the disease severity and progression.

Cisternal, vascular, and parenchymal landmarks in amygdalohippocampectomy for mesial temporal sclerosis: an index case with learnings from 820 resections.

Cortico-amygdalo-hippocampectomy is the most common epilepsy surgery resection in adults and offers excellent outcomes. Seizure outcome benefits range from 75% to 88% with a 2%-4% adverse event rate. The safety profile and outcomes could be enhanced further by clearly defining key surgical landmarks that could also aid tumoral resections in the mesial temporal lobe and selective mesial resections. The authors present their learnings of intraoperative landmarks (cisternal, parenchymal, and vascular) and surgical substeps through an index case of cortico-amygdalo-hippocampectomy with lessons from 820 resections. The video can be found here: https://stream.cadmore.media/r10.3171/2024.4.FOCVID2428.

Superficial Temporal Artery Extended Interposition Graft to Anterior Cerebral Artery Bypass for the Treatment of a Large Fusiform Distal Anterior Cerebral Artery Aneurysm: 2-Dimensional Operative Video.

Fusiform aneurysms of the distal anterior cerebral artery (DACA) are infrequent. Clip reconstruction and sequential progressive clipping have been described in the management of giant thrombosed DACA aneurysms.1,2 Customized revascularization with bypass, side-to-side anastomosis, and trapping of the aneurysmal segment have also been performed for treating DACA aneurysms.3-12 We present a 2-dimensional operative video of superficial temporal artery (STA) to distal anterior cerebral artery bypass, followed by trapping of the aneurysm-bearing segment. A 57-yr-old lady presented with a large ruptured subcallosal fusiform DACA aneurysm (WFNS grade 1, Fisher grade 1). Angiography revealed a 1.3 × 0.9 cm fusiform aneurysm in the DACA. Informed consent was secured from the patient and her family for the surgery and permission was obtained for the publication of the patient's image/surgical video. The frontal and parietal branches of the STA were dissected. The parietal branch was explanted and used as a free interposition graft between the frontal branch (end-to-end anastomosis) and calloso-marginal artery (end-to-side anastomosis). After confirming blood flow through the bypass using Doppler, the aneurysm was trapped and excised. The patient had an uneventful recovery. Her postoperative computed tomography (CT) head revealed no evidence of neurological insult. The patency of the bypass conduit and the complete removal of the aneurysm were confirmed using a digital subtraction angiogram. Histopathological examination revealed an eccentric atheromatous plaque with a lipid core. There was no evidence of intraplaque hemorrhage. This extended STA graft utilizing the frontal and parietal branches of the STA, and its implantation into the distal ACA, offers a novel bypass strategy for tackling fusiform aneurysms of the DACA. Anastomosis to the calloso-marginal artery ensured perfusion of the ACA territory through the pericallosal artery during temporary occlusion.