Intraoperative neural electrode for continuous monitoring of nerve function

Nerve damage is still a major concern in all types of surgery and may result in permanent nerve injury. Real time nerve monitoring can reduce the risk of nerve lesions by continuous surveillance of nerve integrity. A stable proximal stimulation of the nerve and recording at the effector organ is essential and the electrodes should not significantly influence the surgical intervention. This work focuses on the simulation of different electrode designs to compare the results considering the application. Four tripolar electrode designs (cuff, flat, cylindrical and open tube) were simulated by finite-element method. The simulations were performed in 3D and quasi-static electromagnetic case considering the metal-electrolyte interface and the anisotropic conductivity of the nerve. Highest nerve stimulation efficiency was found for the closed cuff design followed by the open tube design. Flat and cylindrical designs were similar. Nevertheless each design has advantages in rela tion to implantation method. The advantages and disadvantages of the electrode designs are discussed.