Single Electrode Deep Brain Stimulation with Dual Targeting at Dual Frequency for the Treatment of Chronic Pain: A Case Series and Review of the Literature.

Deep Brain Stimulation (DBS) has been used to target many deep brain structures for the treatment of chronic pain. The periaqueductal grey and periventricular grey (PAG/PVG) is an effective target but results are variable, sometimes short-lived or subject to tolerance. The centromedian intra-laminar parafascicular complex (CMPf) modulates medial pain pathways and CMPf DBS may address the affective aspects of pain perception. Stimulation of multiple deep brain targets may offer a strategy to optimize management of patients with complex pain symptomatology. However, previous attempts to stimulate multiple targets requires multiple trajectories and considerable expense. Using a single electrode to stimulate multiple targets would help overcome these challenges. A pre-requisite of such a technique is the ability to use different stimulation parameters at different contacts simultaneously on the same electrode. We describe a novel technique in 3 patients with chronic pain syndromes for whom conventional medical and/or neuromodulation therapy had failed using a single electrode technique to stimulate PVG/PAG and CMPf at dual frequencies.