Spinal cord stimulation and cerebral hemodynamics: updated mechanism and therapeutic implications

The effects of spinal cord stimulation (SCS) on cerebral blood flow (CBF) are well known based on experimental investigations, and its vasodilator effect on peripheral arteries is widely used in clinical settings in the treatment of peripheral vascular disease. Since Hosobuchi's [Appl Neurophysiol 1985;48:372-376] first observations on the effects of SCS on CBF were published 22 years ago, many advances have been made in understanding SCS-mediated effects on CBF. This paper reviews the main laboratory observations and analyzes the most significant neurophysiological theories on the SCS-mediated effect on CBF. Most significant experimental data have been discussed, with specific reference to possible mechanisms such as 'functional reversible sympathectomy', cerebral infarction and related ischemic edema, hemodynamic deterioration in experimental combined ischemic-traumatic brain injury and cerebral vasospasm. The authors revised the published experiences in humans with hypoperfusion syndromes and 'adjuvant' locoregional CBF increase in chemotherapy of brain tumors. SCS represents a new perspective in challenging neurosurgical clinical fields such as cerebral ischemia and vasospasm, and seems promising as a new trend of functional neurosurgery in cerebrovascular diseases.