Magnetic resonance imaging–guided laser interstitial thermal therapy as treatment for intractable insular epilepsy in children

Abstract

<jats:sec><jats:title>OBJECTIVE</jats:title><jats:p>Seizure onset within the insula is increasingly recognized as a cause of intractable epilepsy. Surgery within the insula is difficult, with considerable risks, given the rich vascular supply and location near critical cortex. MRI-guided laser interstitial thermal therapy (LiTT) provides an attractive treatment option for insular epilepsy, allowing direct ablation of abnormal tissue while sparing nearby normal cortex. Herein, the authors describe their experience using this technique in a large cohort of children undergoing treatment of intractable localization-related epilepsy of insular onset.</jats:p></jats:sec><jats:sec><jats:title>METHODS</jats:title><jats:p>The combined epilepsy surgery database of Cook Children’s Medical Center and Dell Children’s Hospital was queried for all cases of insular onset epilepsy treated with LiTT. Patients without at least 6 months of follow-up data and cases preoperatively designated as palliative were excluded. Patient demographics, presurgical evaluation, surgical plan, and outcome were collected from patient charts and described.</jats:p></jats:sec><jats:sec><jats:title>RESULTS</jats:title><jats:p>Twenty patients (mean age 12.8 years, range 6.1–18.6 years) underwent a total of 24 LiTT procedures; 70% of these patients had normal findings on MRI. Patients underwent a mean follow-up of 20.4 months after their last surgery (range 7–39 months), with 10 (50%) in Engel Class I, 1 (5%) in Engel Class II, 5 (25%) in Engel Class III, and 4 (20%) in Engel Class IV at last follow-up. Patients were discharged within 24 hours of the procedure in 15 (63%) cases, in 48 hours in 6 (24%) cases, and in more than 48 hours in the remaining cases. Adverse functional effects were experienced following 7 (29%) of the procedures: mild hemiparesis after 6 procedures (all patients experienced complete resolution or had minimal residual dysfunction by 6 months), and expressive language dysfunction after 1 procedure (resolved by 3 months).</jats:p></jats:sec><jats:sec><jats:title>CONCLUSIONS</jats:title><jats:p>To their knowledge, the authors present the largest cohort of pediatric patients undergoing insular surgery for treatment of intractable epilepsy. The patient outcomes suggest that LiTT can successfully treat intractable seizures originating within the insula and offers an attractive alternative to open resection. This is the first description of LiTT applied to insular epilepsy and represents one of only a few series describing the use of LiTT in children. The results indicate that seizure reduction after LiTT compares favorably to that after conventional open surgical techniques.</jats:p></jats:sec>

Stereotactic thermocoagulation for insular epilepsy: Lessons from successes and failures

“…Other techniques based on thermoablation or laser ablation in adults are limited to single cases with poor outcome, without benefit regarding seizures and creating expressive aphasia due to injury of the arcuate fasciculus or seizure‐free outcome but cognitive decline . However, one pediatric series has recently reported a favorable outcome in 10 of 20 patients using laser interstitial thermal therapy, showing that this technique may be an option for insular epilepsy in selected patients. Thermoablations combined with cortectomies reportedly resulted in up to 80% of patients achieving seizure freedom, with 20% experiencing postoperative complications (including 5% of permanent morbidity); however, the additional value of combining both procedures was undetermined .…”

MR-Guided Laser Interstitial Thermal Therapy for Medically Refractory Lesional Epilepsy in Pediatric Patients: Experience and Outcomes

“…We report a mean hospital stay of 1.3 days, while Curry et al [4] reported 3.8 days, Lewis et al [3] reported 1.56 days, and Perry et al [11] reported 1.8 days. No postoperative fevers were noted.…”

“…In 2017, Lewis et al [3] showed a 47% Engel I or II outcome over a mean follow-up duration of 16.1 months in a mixed cohort of 17 patients. In another study of 20 patients with insular epilepsy, Perry et al [11] showed 55% Engel I or II outcomes over a mean follow-up duration of 20.4 months.…”

“…These adverse events were described as inaccurate fiber placements, subarachnoid and intraventricular hemorrhage requiring CSF diversion, failure of the cooling mechanism resulting in breakage of the fiber, steroid-induced gastritis, and a left inferior quadrantanopsia. Perry et al [11] showed a 29% complication rate in their series of 20 patients. These complications were described as mild hemiparesis or expressive aphasia that all resolved or were associated with minimal residual dysfunction within 6 months.…”

Ictal semiology, functional anatomy and multimodal diagnostic in patients with insular epilepsies

“…LITT permits ablation of abnormal tissue while sparing normal cortex. Perry et al [34] reported results of 20 patients which had in 70% normal MRIs. After LITT 50% postoperative were in Engel class 1 and 5% in class 2.…”