Early Diagnosis System of Cartilage Degeneration by Ultrasound

1.利用反射波的小波变换，建立了关节软骨超声测量系统。通过同时测量软骨的动刚度、密度、声速和缺陷，发现反射波的强度表示软骨的动刚度，而持续时间表示软骨的损伤情况。动态刚度、声速和密度随退化的发展而减小。此后，反射波的持续时间增加，出现内反射。通过对胶原酶退行性关节软骨标本的实验证实，反射波的最大强度随着退行性变的发展而减小。5 .采用韧带和半月板切割法建立兔不稳定膝关节模型，采用胶原酶治疗兔软骨变性模型，超声测量结果显示，先在股骨内侧软骨变性，后在股骨外侧软骨变性。除压电陶瓷换能器外，还生产了压电聚合物换能器。结果表明，两种类型均适用于膝关节、髋关节、指关节和椎骨的诊断。测量移植骨-软骨复合体的软骨表面。研究发现，移植后再生软骨的动态刚度比原软骨低，但在日常生活中仍能存活。体外培养兔膝关节软骨的动态刚度明显低于原始软骨。对几种再生方法再生的兔膝关节软骨进行了测量和比较。结果表明，钻孔诱导的骨髓和注入支架的软骨细胞产生了高动态刚度的软骨。

1.Ultrasonic system was established to measure articular cartilage using wavelet transform of reflected wave.2.It is found that strength of reflected wave indicates dynamic stiffness while endurance time indicates damage in the cartilage by simultaneous measurements of dynamic stiffness, density, sound velocity and defects in the cartilage.3.It is found that dynamic stiffness, sound velocity and density reduce with a development of degeneration. Thereafter, endurance time of the reflected wave increases and internal reflection appears.4.It is confirmed by experiment with articular cartilage specimens degenerated by use of collagenase enzyme that maximum strength of the reflected wave decreases with a development of degeneration.5.By means of ultrasonic measurement for unstable rabbit knee model by cutting of ligaments and meniscus and for degenerated cartilage model by collagenase treatment, cartilage at medial femoral chondyle degenerates at first and then degeneration appears at lateral femoral chondyle.6.In addition to the transducer of piezo-electric ceramic, transducer of piezo-electric polymer was produced. Both types were prove applicable to diagnoses of knee joint, hip joint, finger joint and vertebra.7.Cartilage surface of transplanted bone-cartilage complex was measured. It is found that regenerated cartilage after transplantation survives during daily life though its dynamic stiffness is lower than the original cartilage.8.Dynamic stiffness of rabbit knee articular cartilage cultured in vitro was significantly lower than the original cartilage.9.Rabbit knee articular cartilages regenerated by means of several regeneration therapies were measured and compared. According to the result, bone marrows induced to the defect by drilling and chondrocytes injected to scaffold produced cartilage with high dynamic stiffness.