**11. Future trends**

wound infection/meningitis following temporal lobectomy with/without amygdalohippo‐ campectomy and extratemporal lobar/multilobar resections have been reported to be 5.2, 0.8, 1.1 and 19.5, 3.2, 1.9%, respectively [144]. The complication rates have been shown to in‐ crease from 10% during first resective surgery in pediatric patients with complex refractory epilepsy to 50% during second respective surgery [145]. Given this success of epilepsy surgery in controlling seizures with associated morbidity in patients with DRE, there is always a need to improvise on surgical techniques so as to reduce the morbidity while improving the outcomes. Introduction ofMRI-guided LITTin neurosurgery overthe past decades have paved a way to exploration of this technique in patients with DRE. MRgLITT is a minimally invasive stereotactic technique that can be used to ablate the epileptogenic zone and associate fibers so as to simulate the resection and disconnection procedures, respectively. FDA approved Auto LITT in 2009, following a successful Phase 1 multicenter trial investigating the safety of this system in patients with recurrent GBM. In 2012, Curry et al. [146] firstreported the use of MRIguided (1.5T) LITT (Visualase thermal system) in five patents with DRE. In this study, they ablated six epileptic zones (cingulate tuber *n* = 1, mesial temporal sclerosis *n* = 1, hypothala‐ mic hamartoma *n* = 2 and frontal cortical dysplasia *n* = 2) in five patients with DRE and all patients were reported to be seizure-free at 2–13 months of follow up [146]. No complica‐ tions were reported in this study. Another study reported the use of this modality in a 3-yearold with a diagnosis of precocious puberty and pharmacoresistant gelastic seizures and MRI showed type III hypothalamic hamartoma (both pedunculated and sessile component) [88]. Patient underwent MRgLITT using Visualase system without perioperative complications. There was significant improvement in behavior and seizures at 2 weeks after the procedure. At 6 months follow up, patient remained seizure-free with improvement in behavior and selfindulging learning patterns such as playing and entertainment [88]. A year later, Wellmer et al. [147] reported the successful use of 3T MR-guided stereotactic radiofrequency thermal coagulation in two patients with DRE due to type IIB frontal focal cortical dysplasia. These focal cortical dysplasias were identified as epileptogenic zones prior to LITT and one of these lesions was in close proximity to the cortico-spinal tract as elicited by the motor-evoked potentials using in-depth electrodes. Both patients were seizure-free at 12 and 5 months with no persistent postoperative complications (one patient had transient mouth paresis) follow‐ ing thermal coagulation [147]. Authors emphasized the importance of precise placement of radiofrequency probe and destruction of epileptogenic zone, taking into account the sur‐ rounding eloquent area. Gonzalez-Martinez et al. [148] reported robot (ROSA, Medtech Surgical, Inc.) assisted placement of laser probe (Visualase Inc.) under intraoperative MRI guidance to ablate a periventricular heterotopic lesion in a 19-year-old female with DRE of 10 years duration. Authors reported that combination of robot, LITT and intraoperative MRI is a safe, accurate, efficacious and time-efficient minimally invasive technique that can be used for placement and ablation of epileptogenic zone in patients with DRE [148]. Esquenazi and colleagues [149] reported the utility and feasibility of stereotactic MRgLITT (3T) in two patients with DRE and periventricular nodular heterotopia. One patient underwent temporal lobecto‐ my in addition to LITT and was seizure-free during the follow up and another patient had significant seizure control leading to adjustment in medications following the procedure [149]. Former patient with two procedures had transient visual deficit and no complications in

300 Neurooncology - Newer Developments

FDA approved AutoLITT in 2009, following a multicenter trial investigating the efficacy of this modality in patients with recurrent GBM. Laser ablation has currently been investigated as a potential treatment modality in patients with failed stereotactic radiosurgery for brain metastasis (NCT01651078, Laser Ablation after Stereotactic Radiosurgery, LAASR study). Following these results, LITT is likely to be explored in other areas of neuro-oncology.
