Experimental study of contrast-enhanced ultrasound in the evaluation of random-pattern flap blood supply in the early postoperative stage in rats.

Purpose: This study aims to investigate whether contrast-enhanced ultrasound (CEUS) could be used to reveal the status of blood supply of the superficial flap of rat model in the early postoperative stage.

Methods: One viable and one ischemic random-pattern flap were prepared on the left and right back of the same rat respectively with a number of 40. CEUS examinations were applied within 12 h and 7 days postoperatively, and the quantitative measurements of microvascular blood volume (BV) of the base and the end of both flaps were expressed using acoustic intensity as a ratio to that of the healthy skin.

Results: Within 12 h post operation, there was a smaller BV value of the ischemic ends than that of both the ischemic bases and viable ends (p < 0.001), while no difference was indicated between ischemic bases and viable bases or between viable bases and viable ends. The same result was provided 7 days post operation.

Conclusion: Microcirculation of superficial tissues such as random-pattern flaps in this rat model can be assessed quantitatively by CEUS. It could sensitively and accurately reveal the objective status of tissue perfusion in the early postoperative stage.