Brain fMRI during orientation selective epidural spinal cord stimulation

Abstract

Epidural spinal cord stimulation (ESCS) is widely used for chronic pain treatment, and is also a promising tool for restoring motor function after spinal cord injury. Despite significant positive impact of ESCS, currently available protocols provide limited specificity and efficiency partially due to the limited number of contacts of the leads and to the limited flexibility to vary the spatial distribution of the stimulation field in respect to the spinal cord. Recently, we introduced Orientation Selective (OS) stimulation strategies for deep brain stimulation, and demonstrated their selectivity in rats using functional MRI (fMRI). The method achieves orientation selectivity by controlling the main direction of the electric field gradients using individually driven channels. Here, we introduced a similar OS approach for ESCS, and demonstrated orientation dependent brain activations as detected by brain fMRI. The fMRI activation patterns during spinal cord stimulation demonstrated the complexity of brain networks stimulated by OS-ESCS paradigms, involving brain areas responsible for the transmission of the motor and sensory information. The OS approach may allow targeting ESCS to spinal fibers of different orientations, ultimately making stimulation less dependent on the precision of the electrode implantation.

Improvement of brain perfusion in patients with chronic brain ischemia at epidural spinal cord electrical stimulation

“…In recent years, various methods of neuromodulation based on epidural electrical stimulation of the spinal cord have been proposed in clinical practice for the correction of peripheral hemodynamic disorders in patients suffering from refractory angina pectoris or peripheral vasculopathy (6)(7)(8)(9)(10)(11). Also, in many experimental and clinical studies, a positive effect of electrical stimulation of the spinal cord on the hemodynamic and functional parameters of the brain was noted in certain pathological conditions associated with dysfunction of the vascular bed, such as ischemia, subarachnoid hemorrhage, head trauma and brain tumors (10,(12)(13)(14)(15)(16). Most of the conducted clinical and experimental studies devoted to the study of the short-term effect of the upper (at the level of C2-C3 of the cervical spinal cord) electrical stimulation of the spinal cord were performed, as a rule, in acute and severe circulatory disorders, accompanied by critical neurological disorders and the development of a vegetative state, such as stroke, vasospasm, or traumatic brain injury (TBI) (17)(18)(19)(20)(21).…”