Abstract
In a super-aging society, including sports injuries, the number of patients with knee osteoarthritis (OA) has been being expected to increase as a symptom of locomotive syndrome. Recently, transplantation of autologous cultured cartilage has been clinically applied as a treatment for OA. However, the technique of cartilage extraction is highly dependent on the surgeon experience, it is necessary to evaluate quantitative properties of tissue function, e.g. biomechanics. OCDS has been developed to visualize tissue deformation and interstitial fluid flow in cartilage tissue under compression loading can be visualized as tomography of strain rate, making effective use of tomographic tissue velocity obtained by Doppler OCT. However, Doppler OCT with high sensitivity has difficulties in the surgical application because of the severe environment of surgical operation, especially the body motion noise. In this study, the authors propose RMA-OCDS (Robot Manipulation Assisted OCDS), composed mainly of Doppler OCT and a robot manipulator, where the arthroscopic OCT probe is nose-mounted on. This system can stably provide biomechanical function of cartilage tissue, due to 3-axis attitude control of probe to the normal direction of cartilage surface measured by a depth camera. The confirmation experiment was carried out by applying RMA-OCDS to cartilage tissue on a porcine knee joint. The incident angle of probe was converged to the target angle, successfully applying the compression load to cartilage, the spatial and temporal behavior of strain rate could be visualized tomographically. In conclusion, RMA-OCDS was suggested to be effective as an intraoperative diagnosing system for evaluating biomechanical function.
