Numerical analysis of spinal cord stimulation with a 2-electrode percutaneous lead

Spinal cord stimulation (SCS) is a standard treatment method for drug free treatment for chronic pain. In this approach, an electrical current is applied to the region where the chronic pain signals reach the spinal cord and preventing pain sensation from reaching the brain, the pain sensation is been destroyed. To apply current to source of pain, two types of leads are used: percutaneous lead and paddle lead. In this study, numerical studies of current application are done using percutaneous lead with 2-electrode model. Spinal canal is modeled as 3D with epidural fat, CSF, white matter and gray matter tissues. The lead with 2-electrode is placed in epidural fat. One of the electrode is chosen as anode, the other one is as cathode. The surface current density, 70 A/m2, is applied to each electrode. At the contact surface of electrodes and epidural fat, obtained maximum current density is 68.02 mA/cm2 and this value is in the safety limits. The maximum electrical voltage occurred in the spinal canal is 1.14 V and this value is in the interval of perception value for patients.