Neuropsychological outcomes after Gamma Knife radiosurgery for mesial temporal lobe epilepsy: A prospective multicenter study

Abstract

Purpose To assess outcomes of language, verbal memory, cognitive efficiency and mental flexibility, mood, and quality of life (QOL) in a prospective, multicenter pilot study of Gamma Knife radiosurgery (RS) for mesial temporal lobe epilepsy (MTLE). Methods RS, randomized to 20 Gy or 24 Gy comprising 5.5-7.5mL at the 50% isodose volume, was performed on mesial temporal structures of patients with unilateral MTLE. Neuropsychological evaluations were performed at preoperative baseline, and mean change scores were described at 12 and 24 months postoperatively. QOL data were also available at 36 months. Key Findings 30 patients were treated and 26 were available for the final 24 month neuropsychological evaluation. Neither language (Boston Naming Test), verbal memory (California Verbal Learning Test and Logical Memory subtest of the Wechsler Memory Scale-Revised), cognitive efficiency and mental flexibility (Trail Making Test), nor mood (Beck Depression Inventory) differed from baseline. QOL scores improved at 24 and 36 months, with those patients attaining seizure remission by month 24 accounting for the majority of the improvement. Significance The serial changes in cognitive outcomes, mood, and QOL are unremarkable following RS for MTLE. RS may provide an alternative to open surgery especially in those patients at risk of cognitive impairment or who desire a noninvasive alternative to open surgery.

Potential intracranial applications of magnetic resonance–guided focused ultrasound surgery

“…53 Noninvasive techniques involving stereotactic radiosurgery have shown promise for mesial temporal epilepsies, hypothalamic hamartomas, and corpus callosotomy. 1,4,11,13,41 Concerns regarding the use of stereotactic radiosurgery in epilepsy involve the latency of the treatment effect and the potential risk of secondary malignancy due to ionizing radiation, which is very pertinent in a pediatric or young adult population. Transcranial MRgFUS could similarly treat many forms of epilepsy without craniotomy by lesioning of epileptogenic foci or by interrupting the fiber pathways involved in the propagation of epileptiform activity.…”

Epilepsy Surgery: Justified Enthusiasm?

“…Vascular lesions such as arteriovenous malformations that are epileptogenic in nature may also be treated with this technique. A prospective multicenter trial is evaluating the efficacy of this treatment modality in mesial temporal sclerosis [16], and it has also been used successfully in corpus callosotomy [17].…”

Radiosurgery for Medial Temporal Lobe Epilepsy Resulting from Mesial Temporal Sclerosis

“…Srikijvilaikul and colleagues found two deaths during this latency period in a small case series of five patients treated with 20 Gy before seizure remission, likely complications of ongoing seizures [33]. Quigg and colleagues found that language (Boston Naming Test), verbal memory (California Verbal Learning Test and Logical Memory Subtest of the Wechsler Memory Scale-Revised), cognitive efficiency, and mental flexibility (Trail Making Test), and mood (Beck Depression Inventory) did not differ from baseline after radiosurgery, demonstrating long-term neurocognitive safety using established scoring scales, despite the increased potential for necrosis [33].…”