Effective Treatment of Refractory Complex Facial Pain With Motor Cortex Stimulation by Spinal Paddle Electrodes Using Multimodal Imaging

SOURCE: Egyptian Journal of Neurology, Psychiatry and Neurosurgery. 58(1) (no
pagination), 2022. Article Number: 37.

DATE OF PUBLICATION: December 2022.

AUTHOR: Gong A.D.; Gilbert O.E.; Mugge L.A.; Dang D.D.; Dang J.V.; Awan O.; Leiphart J.W.; Shenai M.B.

ABSTRACT
BACKGROUND: Complex facial pain is a debilitating condition with varying etiologies that overall responds poorly to both medical and traditional surgical management. Cortical stimulation is a unique therapeutic intervention which can be effective for some types of complex facial pain syndromes (CFPS). However, the novel use of preoperative functional magnetic resonance imaging (fMRI) and diffusion tensor imaging (DTI) coupled with intraoperative stimulation mapping and phase reversal to improve the accuracy for placement of spinal paddle electrodes in motor cortex stimulation, to our knowledge, has not been reported in the
literature.

CASE PRESENTATION: Here, we present a unique case of a 56-year-old male who developed left-sided complex facial pain syndrome after a stroke refractory to medical management and peripheral nerve stimulation. He previously underwent microvascular decompression (MVD) with limited control of his left-sided facial pain. In order to treat this, the patient underwent motor cortex stimulation. The motor strip of the face and tongue was identified preoperatively with functional magnetic resonance imaging (fMRI) and diffusion tensor imaging (DTI). Intraoperatively, phase reversal was used to identify corticospinal tracts and stimulus mapping confirmed the location before the epidural placement of two spinal paddle electrodes. Postoperatively, the patient reported significant reduction in pain levels, burning dysesthesias, and intensity and frequency of symptoms. This trend continued, and the patient experienced equivalent levels of relief at 6 months.

CONCLUSION(S): This is a rare case report of successful motor cortex stimulation with the novel preoperative use of fMRI and DTI, coupled with intraoperative
functional mapping, to successfully guide the placement of spinal paddle electrodes for the treatment of CFPS.