Jie Tang, Presenter: Nothing to Disclose

Faqin Lv, Abstract Co-Author: Nothing to Disclose

Yukun Luo MD, Abstract Co-Author: Nothing to Disclose

Tengfei Yu, Abstract Co-Author: Nothing to Disclose

Xia Xie, Abstract Co-Author: Nothing to Disclose

Jiangke Tian, Abstract Co-Author: Nothing to Disclose

Tanshi Li, Abstract Co-Author: Nothing to Disclose

This study was to explore imaging feature of muscle crush injury of extremity on contrast enhanced ultrasound (CEUS) by an animal experiment.

Twenty-eight New Zealand rabbits between 1 and 1.5 years old and weighing 2.8-3.5 kg were anesthetized by intramuscular pentobarbital sodium (30 mg/kg). A special balloon cuff device was used to create left hind leg crush injury with a force of (18.6kP). 23 of the 28 rabbits had crush injury of extremity and survived for 72 hours. CEUS examinations was performed using a CX50 system (Philips Medical Systems, Andover, MA). A L12-3 transducer was used in this study. CEUS examination was performed using pulse inversion harmonics and power modulation at a mechanical index of 0.07. CEUS evaluated infusion model and contrast intensity in crush region of hind leg. Peak intensity (PI), a CEUS parameter, was anylized by comparing with serum creatinekinase (CK) and myoglobin (MYO).

The area of crushed region in left hind leg was 60 cm2, accounting for 2.6-3.0% of body surface area. At 30min, 2h, 6h, 24h and 72h after the release of the crushing pressure, the crushed regions all showed rapid enhancement and the intensity were higher than those of no-crushed regions. The time-intensity curves of crushed regions appeared as fast wash-in and slow wash-out. PIs of the rushed regions were higher obviously than those of no-crushed regions (P＜0.001). PI of rushed regions at 2 h was highest and one at 24 h was lowest. ROC curves were employed in diagnosis value of PI for crushed region. And PIs showed positive correaltion with CK and MYO and the correlation coefficient = 0.833-0.996.

After the release of the crushing pressure CEUS showed that blood perfusion of crushed muscle was increased obviously. PI indicated the blood perfusion severity, by which the crushed injury was evaluated. And it may suggest a potential alternative for evaluating ischemia reperfusion of muscle crush injury in extremity.

Many modalities can evaluate muscle crush injury. However, it is not certain exactly how local muscle blood perfuse after the release of the crushing pressure. And this is important for treatment.

Tang, J, Lv, F, Luo, Y, Yu, T, Xie, X, Tian, J, Li, T, Contrast-enhanced Ultrasound Imaging Feature of the Muscle Crush Injury of Extremity: An Animal Experiment.  Radiological Society of North America 2011 Scientific Assembly and Annual Meeting, November 26 - December 2, 2011 ,Chicago IL. http://archive.rsna.org/2011/11009248.html