Stereo-electroencephalography in the setting of a preexisting deep brain stimulation device: illustrative case.

Background: Deep brain stimulation (DBS) and responsive neurostimulation are increasingly being used to treat drug-resistant epilepsy (DRE). However, patients who experience partial or limited improvement in seizure control could require additional surgical interventions or refinement of their epilepsy network characterization, including further stereo-electroencephalography (SEEG) investigations. SEEG in the setting of previously implanted hardware demonstrates a myriad of technical challenges. The authors present the first reported demonstration of SEEG electrode implantation with a preexisting DBS device.

Observations: The patient was a 36-year-old male with a history of severe DRE with focal impaired awareness seizures beginning at 7 years of age. Despite having a bilateral DBS device for the anterior nucleus of the thalamus, he continued to have 1-2 seizures per day and was offered SEEG. The patient tolerated the surgery well without any morbidity, with a successfully improved definition of his epilepsy network. SEEG allowed the medical team to titrate stimulation settings while following intracranial electrographic response.

Lessons: SEEG in the setting of preexisting DBS can be performed safely without damage to functioning hardware, and the authors obtained characterization and localization of the epilepsy network. Further follow-up will be needed to assess the efficacy outcomes of additional intervention in this patient. https://thejns.org/doi/10.3171/CASE24854.