Abstracts

Rationale: A substantial number of children with pharmacoresistant epilepsy have seizures related to focal lesions. There is mounting evidence that surgical resection or ablation of such lesions and associated seizure foci in the brain during childhood results in significant improvement of seizure control and quality of life; however, not all lesions are amenable to traditional neurosurgical approaches. Stereotactic laser ablation has been demonstrated by others to be successful in children with epilepsy and is described in detail by Curry et al. (2012).We report the first five consecutive cases of children with pharmacoresistant lesional epilepsy who underwent laser thermal ablation at our center.Methods: Since January 2013, five children were selected to undergo this procedure (Table 1). Imaging had revealed focal lesions and noninvasive studies were adequate to determine the extent of the focus of seizure onset. Stereotaxic positioning of laser catheters was followed by MRI-guided laser interstitial thermal therapy (LITT) using the Visualase Thermal Therapy System (Visualase, Inc., Houston, TX).Results: Four children underwent a single procedure. One with a dysembryoplastic neuroepithelial tumor and another with periventricular nodular heterotopia underwent implantation of a single fiber. Two patients, both with focal cortical dysplasia, underwent implantation of two laser fibers as the size and conformation of their lesions was not amenable to single catheter ablation. One child with a giant hypothalamic hamartoma (Patient 5) first underwent craniotomy and partial resection, followed by two LITT procedures resulting in partial ablations. Post-operative length of stay ranged from 1-3 days, the novelty of the procedure resulting in stays that were longer than necessary. The patient with the giant hamartoma had catheters which were imperfectly placed, reducing their efficacy. Other than this, there were no unexpected complications. All patients had substantial and worthwhile seizure reduction following LITT procedures: three are seizure free, one has had rare recurrent seizures related to non-adherence to medical regimen, and one (patient 5) has had rare clusters of tonic seizures.Conclusions: MRI-guided LITT is a recently approved treatment that may significantly decrease the cost and comorbidities associated with open surgical resection in a select group of children with lesional epilepsy. Further study is needed to determine whether effectiveness is comparable to open lesionectomy. References: Curry DJ. Gowda A. Boulby PA. McNichols RJ. Wilfong AA. MR-guided stereotactic laser ablation of epileptogenic foci in children. Epilepsy Behav. 24(4):408-14, 2012 Aug.