Value of contrast-enhanced ultrasound on assessment of limb muscle crush injury: an animal experiment

Abstract

Objective To explore the diagnostic value of quantitative contrast-enhanced ultrasonography(CEUS) for crush injury in the hind limb muscle of rabbits. Methods A totle of 120 New Zealand white rabbits were randomized to receive compression on the left hind limb for either 2 h(n=56) or 4 h(n=56) to induce muscle crush injury, another 8 animals were not injured and served as normal controls. CEUS parameters such as peak intensity(PI), area under curve(AUC), ascending slop(AS) and descending slop(DS) were measured at 0.5 h, 2 h, 6 h, 24 h, 3 d, 7 d, 14 d after decompression. Results Compared with the uninjured muscle, reperfusion of the injured muscles showed early and high enhancement in CEUS. The time-intensity curve showed a trend of rapid lift and gradual drop. The PI and AUC values differed significantly among the three groups and were positively correlated with serum and tissue biomarkers. Rabbits of the 4 h compression group showed significantly higher PI and AUC values compared with the 2 h compression group at each time points. Conclusions CEUS can effectively detect muscle crush injury and monitor dynamic changes of the injured muscle in rabbits.PI and AUC are promising diagnostic parameters for this disease. CEUS might play an important role in the pre-hospital and bedside settings for the diagnosis of muscle crush injury. Key words: Ultrasonography; Microbubbles; Muscle; Crush injury