Centromedian–Parafascicular and Somatosensory Thalamic Deep Brain Stimulation for Treatment of Chronic Neuropathic Pain: A Contemporary Series of 40 Patients

Abstract

Introduction: The treatment of neuropathic and central pain still remains a major challenge. Thalamic deep brain stimulation (DBS) involving various target structures is a therapeutic option which has received increased re-interest. Beneficial results have been reported in several more recent smaller studies, however, there is a lack of prospective studies on larger series providing long term outcomes. Methods: Forty patients with refractory neuropathic and central pain syndromes underwent stereotactic bifocal implantation of DBS electrodes in the centromedian–parafascicular (CM–Pf) and the ventroposterolateral (VPL) or ventroposteromedial (VPM) nucleus contralateral to the side of pain. Electrodes were externalized for test stimulation for several days. Outcome was assessed with five specific VAS pain scores (maximum, minimum, average pain, pain at presentation, allodynia). Results: The mean age at surgery was 53.5 years, and the mean duration of pain was 8.2 years. During test stimulation significant reductions of all five pain scores was achieved with either CM–Pf or VPL/VPM stimulation. Pacemakers were implanted in 33/40 patients for chronic stimulation for whom a mean follow-up of 62.8 months (range 3–180 months) was available. Of these, 18 patients had a follow-up beyond four years. Hardware related complications requiring secondary surgeries occurred in 11/33 patients. The VAS maximum pain score was improved by ≥50% in 8/18, and by ≥30% in 11/18 on long term follow-up beyond four years, and the VAS average pain score by ≥50% in 10/18, and by ≥30% in 16/18. On a group level, changes in pain scores remained statistically significant over time, however, there was no difference when comparing the efficacy of CM–Pf versus VPL/VPM stimulation. The best results were achieved in patients with facial pain, poststroke/central pain (except thalamic pain), or brachial plexus injury, while patients with thalamic lesions had the least benefit. Conclusion: Thalamic DBS is a useful treatment option in selected patients with severe and medically refractory pain.

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

“…3,4 DBS for FNPS fell out of favor after failing to gain approval from the FDA once it began overseeing medical devices in 1989. 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.…”

Where Are We with Deep Brain Stimulation? A Review of Scientific Publications and Ongoing Research

“…A less commonly used target that shows promise for treating OCD and depression is the inferior thalamic peduncle [31,32]. Structures that belong to both the motor and limbic circuits, such as the caudate and centromedian/parafascicular complex, collectively comprise 1.4% of targets and are used for OCD, Tourette syndrome, and pain [33][34][35]. Memory circuit structures are the least targeted at 1.0% of all targets and include the fornix and nucleus basalis to treat dementias.…”

Neuromodulation for Trigeminal Neuralgia

“…This anatomical proximity to the PAG and PVG renders a question on whether it is possible that the analgesic effects of PAG or PVG DBS is partially induced by the leakage of electrical energy to the CM/PF [ 37 ]. Recently, analgesic DBS of the CM/PF showed sustained improvement of chronic neuropathic pain in long-term observations of >4 years [ 1 ]. The best stimulation effects were obtained in patients with facial pain, brachial plexus injury, or central pain.…”