Radiofrequency-thermocoagulation for Epileptogenic Lesions at the Bottom of Sulci near the Arcuate Fasciculus
Abstract number :
3.46
Submission category :
9. Surgery / 9B. Pediatrics
Year :
2024
Submission ID :
486
Source :
www.aesnet.org
Presentation date :
12/9/2024 12:00:00 AM
Published date :
Authors :
Presenting Author: Yutaro Takayama, MD, PhD – Department of Neurosurgery, Yokohama City University
Masaki Sonoda, MD, PhD – Yokohama City University
Takahiro Hayashi, MD, PhD – National Center of Neurology and Psychiatry
Takahiro Moro, MD – Yokohama City University
Yuiko Kimura, MD, PhD – National Center of Neurology and Psychiatry
Keiya Iijima, MD, PhD – National Center of Neurology and Psychiatry
Masaki Iwasaki, MD, PhD – National Center of Neurology and Psychiatry
Tetsuya Yamamoto, MD, PhD – Yokohama City University
Rationale: Stereotactic ablation techniques such as radiofrequency thermocoagulation (RFTC) and laser interstitial thermal therapy (LITT) based on the results of stereoelectroencephalography (SEEG) are attracted as minimally invasive surgery for refractory epilepsy with a deep-located lesion. Stereotactic ablation has been suggested to be less effective in terms of seizure control than resective surgery in some reports. It is difficult to obtain sufficient seizure control only by the SEEG-guided RFTC, which partly coagulate the epileptogenic zone. However, RFTC can be planned to target the entire epileptogenic zone exhaustively, maximizing the chance of seizure freedom while minimizing the risk of cortical damage around the target. Cortical resection targeting lesions at the bottom of the sulci (BOS) near the arcuate fasciculus is often avoided due to the significant challenge of preserving verbal function. RFTC may offer an alternative strategy for such patients. Here, we report the first three patients who underwent RFTC targeting the BOS lesions near the arcuate fasciculus.
Methods: We report our early experiences of three pediatric patients (three girls) with intractable epilepsy with focal cortical dysplasia at the BOS near the arcuate fasciculus who underwent RFTC after SEEG in 2021~2024, with a postoperative observation period of more than 100 days.
Results: Median age at surgery was 4 (2-15) years, and median postoperative follow-up was 876 (113-1212) days. Two patients had daily bilateral tonic seizures, and the other patient had monthly impaired awareness seizures. All patients were right-handed and had MRI abnormalities and hypometabolism on FDG-PET at the BOS in the left frontal or parietal operculum. The lesions were defined as the epileptogenic zones to be treated. RFTC was performed with the Leksell stereotactic frame after planning to target the entire epileptogenic zone with multiple 5-mm sphere coagulation models. The median number of trajectories was 13 (13-18), and the median number of coagulated lesions was 48 (20-52). The median coagulation efficiency, representing the treatment volume ratio to target volume, was 89.9% (75.8-91.7%). All patients obtained seizure freedom at 100 days after RFTC and remained seizure-free at the last follow-up. No permanent neurological complications, including verbal deficits, occurred after RFTC. The postoperative MRI showed no acute infarction in the arcuate fasciculus.
Conclusions: RFTC may be a feasible alternative for refractory epilepsy patients with epileptogenic lesions near eloquent cortices. This technique may be safer than resective surgery in terms of preventing damage to arcuate fibers and minor but critical infarction around the bottom of the sulci, which is difficult to avoid with cortical resection. Careful planning is essential to prevent vascular complications since this surgery tends to require many trajectories and coagulation lesions. Further experience will be needed to make this technique safer and more efficient.
Funding: None
Surgery