Realistic anatomically detailed open-source spinal cord stimulation (RADO-SCS) model.

Objective: Computational current flow models of spinal cord stimulation (SCS) are widely used in device development, clinical trial design, and patient programming. Proprietary models of varied sophistication have been developed. An open-source model with state-of-the-art precision would serve as a standard for SCS simulation.

Approach: We developed a sophisticated SCS modeling platform, named Realistic Anatomically Detailed Open-Source Spinal Cord Stimulation (RADO-SCS) model. This platform consists of realistic and detailed spinal cord and ancillary tissues anatomy derived based on prior imaging and cadaveric studies. In our finite element model of the T9-T11 spine levels, we represented the following tissues: vertebrae, intervertebral disc, epidural space, epidural space vasculature, dura mater, dural sac, intraforaminal tissue, cerebrospinal fluid (CSF), whitematter, spinal cord vasculature, Lissauer's tract, gray matter, dorsal and ventral roots and rootlets, dorsal root ganglion (DRG), sympathetic chain (trunk and ganglion), thoracic aorta and its branching, peripheral vasculature, and soft tissues (thorax). As an exemplary application to illustrate the model workflow, we simulated a bipolar SCS montage and calculated the corresponding activation thresholds for individual axons populating the spinal cord.

Main Results: RADO-SCS provides state-of-the-art precision across 19 tissue compartments. The resulting model calculations of the electric fields generated in the white-matter and gray matter, and the axonal activation thresholds are broadly consistent with prior simulations.

Significance: The RADO-SCS can be used to simulate any SCS approach with both unprecedented resolution (precision) and transparency (reproducibility). Freely-available online, the RADO-SCS will be updated continuously with version control.