Beta Oscillations in the Sensory Thalamus During Severe Facial Neuropathic Pain Using Novel Sensing Deep Brain Stimulation.

OBJECTIVE: Advancements in deep brain stimulation (DBS) devices provide a unique opportunity to record local field potentials longitudinally to improve the efficacy of treatment for intractable facial pain. We aimed to identify potential electrophysiological biomarkers of pain in the ventral posteromedial nucleus (VPM) of the thalamus and periaqueductal gray (PAG) using a long-term sensing DBS system. MATERIALS AND METHODS: We analyzed power spectra of ambulatory pain-related events from one patient implanted with a long-term sensing generator, representing different pain intensities (pain >7, pain >9) and pain qualities (no pain, burning, stabbing, and shocking pain). Power spectra were parametrized to separate oscillatory and aperiodic features and compared across the different pain states. RESULTS: Overall, 96 events were marked during a 16-month follow-up. Parameterization of spectra revealed a total of 62 oscillatory peaks with most in the VPM (77.4%). The pain-free condition did not show any oscillations. In contrast, ß peaks were observed in the VPM during all episodes (100%) associated with pain >9, 56% of episodes with pain >7, and 50% of burning pain events (center frequencies: 28.4 Hz, 17.8 Hz, and 20.7 Hz, respectively). Episodes of pain >9 indicated the highest relative ß band power in the VPM and decreased aperiodic exponents (denoting the slope of the power spectra) in both the VPM and PAG. CONCLUSIONS: For this patient, an increase in ß band activity in the sensory thalamus was associated with severe facial pain, opening the possibility for closed-loop DBS in facial pain.

Deep Brain Stimulation for the Treatment of Hemichorea: Case Series and Literature Review.

Background: Hemichorea (HC) and its severe form hemiballismus (HB) are rare movement disorders which can be medically refractory to treatments and may need surgical intervention. Case Report: We report 3 patients with HC-HB who had meaningful clinical improvement with unilateral deep brain stimulation (DBS) of the globus pallidus interna (GPi). We identified 8 prior cases of HC-HB treated with GPi-DBS, and a majority of these patients experienced significant improvement in their symptoms. Discussion: GPi-DBS can be considered in medically refractory HC-HB in carefully selected patients. However, data is limited to small case series and further studies are needed.