A nerve cuff electrode for controlled reshaping of neural geometry

The purpose of this study is the development of a silicone nerve cuff electrode that reshapes nerve geometry slowly and controllably. Previous work using a reshaping electrode called the Flat Interface Nerve Electrode (FINE) has shown that the FINE has the ability to reshape the nerve and fascicles into elongated ovals. Reshaping the geometry too quickly may cause neural insult. The Slowly Closing Flat Interface Nerve Electrode (SC-FINE) is designed to control the reshaping period and alleviate any potential nerve compression injury. This is done by combining the reshaping properties of the FINE and the controllable degradation of a biodegradable polymer. Poly (DL lactic-co-glycolic) acid (PLGA) is applied to both sides of a stretched FINE to increase the opening height and control the time period of reshaping. Twenty eight SC-FINEs were manufactured. Their opening heights were measured and the average was 1.72 mm ± 0.47 mm. Preliminary in-vitro experiments to test the reshaping period were performed using 75/25 lactic to glycolic copolymer. Three SC-FINEs, with no delamination of the PLGA film, returned to the original geometry within 15 days ± 8 hours.