A new strategy for treating drug-resistant focal aware seizures: thalamic specific nuclei deep brain stimulation. Illustrative case.

BACKGROUND

Focal aware seizures (FASs) are relatively common and frequently pharmaco-resistant. If the seizure onset zone (SOZ) is in eloquent cortical areas, making resective surgery risky and inadvisable, deep brain stimulation (DBS) of the anterior nucleus of the thalamus, which is efficacious in less than half of the cases, has been the main alternative. New targets should be searched to address this deficiency. The present study aims to determine if DBS of different thalamic specific nuclei can modulate the abnormal electrical activity of the SOZ located in their respective cortical projection areas. Herein, the authors present the first patient in an ongoing trial.

OBSERVATIONS

A 60-year-old female patient presented with 25-year history of pharmaco-resistant focal aware visual seizures frequently evolving to focal impaired awareness seizures. The SOZ was in the right occipital lobe (positron emission tomography-computed tomography/video electroencephalography). Magnetic resonance imaging was normal. She underwent ipsilateral lateral geniculate nucleus (LGN) DBS procedure. After a 24-month follow-up, seizure frequency decreased by 97%, improving quality of life and daily functioning without complications.

LESSONS

This is the first time the LGN has been targeted in humans. The results support the hypothesis that led to this study. This strategy represents a paradigm shift in the way of treating pharmaco-resistant FASs not amenable to resective surgery.