Less is more: novel less-invasive surgical techniques for mesial temporal lobe epilepsy that minimize cognitive impairment.

PURPOSE OF REVIEW New minimally invasive techniques are becoming available to treat focal-onset epilepsy. The open surgical treatment of mesial temporal lobe epilepsy (MTLE), although associated with high rates of seizure freedom, is confounded by adverse impacts on neurocognitive function. This review covers new techniques being explored for surgical treatment of MTLE that in early studies have been achieving high seizure-free rates with preservation of memory and other functions referable to the mesial and lateral temporal regions. RECENT FINDINGS Multiple subpial transections of the hippocampus, and stereotactic approaches including radiofrequency ablation and laser interstitial thermal therapy have achieved rates of seizure freedom comparable to open resection but with fewer neurocognitive adverse effects. Electrical neuromodulation approaches, including responsive neurostimulation, direct hippocampal stimulation, and thalamic deep brain stimulation preserve cognitive function and achieve significant seizure suppression, but have not yet achieved high seizure-free rates. SUMMARY With the recent success in minimally invasive approaches with respect to seizure freedom and preservation of neurocognitive functions, it is predicted that fewer patients will be receiving 'classic' open resections for MTLE such as temporal lobectomy. These new approaches also promise to decrease discomfort, time away from work, and healthcare utilization.

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