Introduction: Stereotactic magnetic resonance imaging-guided laser amygdalohippocampotomy (SLAH) is a minimally invasive approach to surgical treatment of drug-resistant mesial temporal lobe epilepsy (MTLE). Although short term outcomes in two small series have been reported (Willie et al., 2014; Kang et al., 2016), one year outcomes represent the gold standard by which to compare SLAH to standard open temporal surgery such as anterior temporal lobectomy (ATL) or selective amygdalohippocampectomy (SAH), a recent meta-analysis of which demonstrated one-year seizure freedom rates of 75% and 67%, respectively. The subset with mesial temporal sclerosis (MTS) yielded higher rates (78% verses 71%, respectively). Here we present a consecutive series of 41 patients with MTLE that underwent SLAH.
Methods: All 41 patients with MTLE (25 of whom had MTS) who underwent SLAH at our institution and who had follow-up =12 months were included. Surgical outcome was stratified by Engel's classification (class 1 = free of disabling seizures). Results were retrospectively analyzed as a non-inferiority trial with the objective performance criterion (OPC) = 67% (equivalent to SAH), and the non-inferiority margin (f) = 8% (= absolute risk reduction between ATLAH and SAH). The subgroups with and without MTS were similarly analyzed (OPC=71%, f=7%).
Results: At one-year following SLAH 56.1% (95% CI ±15.2%) of all MTLE patients and 64.0% (95% CI ±18.8%) of MTS patients were free of disabling seizures (Engel 1) suggesting statistical non-inferiority to SAH. Fewer (43.8%, CI 95% ±24.3%) of non-MTS patients were seizure-free.
Conclusions: In this largest single center experience to date, SLAH was non-inferior to SAH at one year, with superior results in patients with MTS. Compared to open temporal lobe surgery, SLAH is an effective minimally invasive alternative with a favorable neurocognitive profile. In the minority of patients that do not achieve seizure freedom, SLAH presents no barrier to additional open surgery.
Patient Care: Minimize cognitive impact and surgical complications from standard surgery for mesial temporal lobe epilepsy
Learning Objectives: Understand the outcome of stereotactic laser amygdalohippocampotomy (SLAH) for mesial temporal lobe epilepsy as compared to standard open resection surgery.
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