Department of Physics and Mathematics, University of Eastern Finland, Kuopio, Finland.
IEEE Trans Ultrason Ferroelectr Freq Control. 2011 Jan;58(1):148-55. doi: 10.1109/TUFFC.2011.1781.
A local cartilage injury can trigger development of posttraumatic osteoarthritis (OA). Surgical methods have been developed for repairing cartilage injuries. Objective and sensitive methods are needed for planning an optimal surgery as well as for monitoring the surgical outcome. In this laboratory study, the feasibility of an arthroscopic ultrasound technique for diagnosing cartilage injuries was investigated. In bovine knees (n = 7) articular cartilage in the central patella and femoral sulcus was mechanically degraded with a steel brush modified for use under arthroscopic control. Subsequently, mechanically degraded and intact adjacent tissue was imaged with a high frequency (40 MHz) intravascular ultrasound device operated under arthroscopic guidance. After opening the knee joint, mechanical indentation measurements were also conducted with an arthroscopic device at each predefined anatomical site. Finally, cylindrical osteochondral samples were extracted from the measurement sites and prepared for histological analysis. Quantitative parameters, i.e., reflection coefficient (R), integrated reflection coefficient (IRC), apparent integrated backscattering (AIB), and ultrasound roughness index (URI) were calculated from the ultrasound signals. The reproducibilities (sCV %) of the measurements of ultrasound parameters were variable (3.7% to 26.1%). Reflection and roughness parameters were significantly different between mechanically degraded and adjacent intact tissue (p < 0.05). Surface fibrillation of mechanically degraded tissue could be visualized in ultrasound images. Furthermore, R and IRC correlated significantly with the indentation stiffness. The present results are encouraging; however, further technical development of the arthroscopic ultrasound technique is needed for evaluation of the integrity of human articular cartilage in vivo.
局部软骨损伤可引发创伤后骨关节炎（OA）。已经开发出用于修复软骨损伤的外科方法。需要客观和敏感的方法来规划最佳手术以及监测手术结果。在这项实验室研究中，研究了关节镜超声技术诊断软骨损伤的可行性。在牛膝关节（n = 7）中，使用专门为关节镜控制下使用而修改的钢刷刷机械降解中央髌骨和股骨沟的关节软骨。随后，使用在关节镜引导下操作的高频（40 MHz）血管内超声设备对机械降解和相邻的完整组织进行成像。打开膝关节后，还在每个预定义的解剖部位使用关节镜设备进行机械压痕测量。最后，从测量部位提取圆柱形骨软骨样本并准备进行组织学分析。从超声信号中计算出定量参数，即反射系数（R）、积分反射系数（IRC）、表观积分背散射（AIB）和超声粗糙度指数（URI）。超声参数测量的重现性（sCV％）是可变的（3.7％至26.1％）。机械降解和相邻完整组织之间的反射和粗糙度参数存在显著差异（p <0.05）。机械降解组织的表面纤维化在超声图像中可见。此外，R 和 IRC 与压痕刚度显著相关。目前的结果令人鼓舞；然而，需要进一步开发关节镜超声技术，以评估体内人类关节软骨的完整性。
