Directional Deep Brain Stimulation Can Target the Thalamic “Sweet Spot” for Improving Neuropathic Dental Pain

Abstract

BACKGROUND Neuropathic dental pain (NDP) is a chronic pain condition that is notoriously difficult to treat. To date, there are no deep brain stimulation (DBS) studies on this specific pain condition and no optimal target or “sweet spot” has ever been defined. OBJECTIVE To determine the optimal thalamic target for improving this condition by utilizing the steering abilities of a directional DBS electrode (Vercise CartesiaTM Model DB-2202-45, Boston Scientific) METHODS A literature search and review of our database identified 3 potential thalamic targets. A directional lead was implanted in a patient with NDP and its current steering used to test the effects in each nucleus. The patient reported her pain after 2 wk of stimulation in a prospective randomized blinded trial of one. Quality of life measurements were performed before and after 3 mo on their best setting. RESULTS We identified 3 potential nuclei: the centromedian (CM), ventral posterior medial (VPM), and anterior pulvinar. The best results were during VPM stimulation (>90% reduction in pain) and CM stimulation (50% reduction). Following 3 mo of VPM-DBS in combination of lateral CM stimulation, their pain disability index dropped (from 25 to 0) and short form 36 improved (from 67.5 to 90). CONCLUSION VPM stimulation in combination with CM stimulation is a promising target for NDP. DBS electrode directionality can be used to test multiple targets and select a patient specific “sweet spot” for NDP treatment.

Directional electrodes in deep brain stimulation: Results of a survey by the European Association of Neurosurgical Societies (EANS)

“…Most experts believed that mainly patients with well-established indications, such as PD, tremor and dystonia would benefit most from directionality. This is very much in line with the literature so far, where most published studies are on PD and tremor ( Bruno et al, 2021 ; Shao et al, 2020 ; Rebelo et al, 2018 ; Schnitzler et al, 2022 ), with only a small number of case reports or small case series on dystonia, pain or psychiatric diseases ( Abel et al, 2021 ; Asahi et al, 2021 ; Krüger et al, 2021c ; Coenen et al, 2022 ; Lopez et al, 2021 ), and no studies on depression or epilepsy.…”

Deep brain stimulation for chronic pain: a systematic review and meta-analysis

“…The heterogeneity measures (tau^2, tau, I^2) also remained similar. Similarly, omitting Holland et al (2018) , Cappon et al (2021) , Krüger et al (2021) , and Abreu et al (2022) did not substantially affect the overall results. The p -value remained <0.0001, and the effect sizes and heterogeneity measures remained consistent.…”

Functional MRI–Guided Motor Cortex and Deep Brain Stimulation for Intractable Facial Pain: A Novel, Personalized Approach in 1 Patient

“…5,26 Small, retrospective case series have since been published that suggest the efficacy of this treatment paradigm, both in FNPS and in TDPS. 5,6,27,28 DBS of the PAG reduces nociceptive pain, likely by stimulating endogenous opioid production, although the exact mechanism is not clear. 3,26,29 DBS of the VPM has been used for the treatment of neuropathic facial pain and is believed to work by inhibiting aberrant neuronal firing within the thalamic somatosensory relay centers that allow for discrimination of location and intensity of pain.…”

“…3,26,30 VPM-DBS has also recently shown favorable responses for dental pain, although our patient was evaluated by a dentist and was not found to have dental pathology responsible for his facial pain. 27 Studies have shown that the VPM and PAG can be stimulated simultaneously for a synergistic effect. 5,6,29,31 MCS is a more recently developed intervention and acts by a multimodal, incompletely understood mechanism, perhaps by altering thalamocortical circuitry and pain perception in the cingulate gyrus.…”