Empirical Study Of High-frequency Ultrasound Observing Sciatic Muscle Coup Injury

Objective: The aim of this study is to observe the rabbit muscle injury models by High-frequency Ultrasound, and compared with pathological changes, to explore the relation between the sonographic appearance and pathological changes from posttraumatic muscles. So we can prove the feasibility and ability of high-frequency ultrasound in diagnosing muscle injury, and provide a dependent method for clinical diagnosis.Methods: Muscle injury models on 22 rabbits were set up and immediately inspected with ultrasound and then repeated on the 1st, 3rd, 7th, 14th, 21st, 28th days after injury. The muscles'transaction and longitudinal characteristic image were displayed, observed and documented muscle's thickness, echo and color signal, looking for the most affluence section of the vessel and grading color signal by Adler, Then if a persistent color signal was displayed, the blood flow(Q) and resistant index(RI) of the vessel in the same position were measured on PW, repeated 3 times, and got the average value. Randomly selected one rabbit was sacrificed to obtain the sample of injured muscle tissue for HE light microscopic in the different time respectively.Results: The rabbits'affected limbs became hypergasia and the injured muscles were swell, the skin was cyanotic. Then it became better and normal gradually after seven days.Ultrasonic inspection: The thickness, echo, color signal, and blood flow were obtained from the injured muscle had significant differences in different time(p < 0.05).â‘ thickness: the thickness was immediately increased after injury, the most thick in the 1st day, it became thinner in the following days, instant to the 7th day compared with the normal thickness (p< 0.05).â‘¡echo: the muscle echo was immediately increased after injury, the most thick in the 1st day, it became lower in the following days, instant to the 7th day compared with the normal thickness (p< 0.05).â‘¢color signal: the color signal was immediately increased after injury, in the gradeâ…¢, it became fewer in the first day, in the 3rd to the 21st day, the color signal were in gradeâ…¡toâ…¢, instant to the 21st day compared with the normal color signal (p< 0.05).â‘£Q and RI: the blood flow was increased after injury, instant to the 21st day compared with the normal blood flow (p< 0.05), the 1st to the 21st day compared with the normal RI (p< 0.05).Pathological detection: The defected muscles'color became more deeply, the structure was irregularity, and hemorrhage emerged immediately. The pathological changes included hemorrhage, edema, degeneration, muscular necrosis and infiltration of inflammatory cells, regenerate vessels and hyperplasic fibrous tissue. The inflammatory reaction was more obvious on the 1st to 3rd days and hyperblastosis was primary after 7 days.Conclusion: High-frequency ultrasound could display the rabbit muscle's texture and diagnose the changes in the different process of injured muscle, the sonogram have the character image in the different period of the injury and it can reflect the pathological changes. High-frequency is dependable image method for diagnosing muscle injury.