ABSTRACT
Objective:To explore the diagnostic application and characteristics of contrast-enhanced ultrasound in exertional rhabdomyolysis (ERM).Methods:Three cases of ERM patients admitted to Department of Neurology, the First Medical Center of Chinese People′s Liberation Army General Hospital in August 2019 were selected and clinical data of the patients were collected including medical history, serum muscle enzyme, electromyography, magnetic resonance imaging (MRI) and dynamic contrast-enhanced ultrasound of the thigh muscles within one week after onset.Results:All three patients had muscle soreness and dark urine after exercise and their serum muscle enzyme level exceeded five times of normal value which could be definitely diagnosed as ERM. Skeletal muscle MRI showed equal or slightly longer T 1, longer fat-suppressed T 2 weighted fluid attenuated inversion recovery images, and high diffusion weighted imaging signal. In this group, one case of femur muscle MRI showed adductor longus and semitendinosus myopathy, other two cases showed quadriceps. All cases′ MRI score was grade one. Echogenic enhancement can be seen in normal ultrasound of diseased skeletal muscle. Contrast-enhanced ultrasound showed a dynamic strengthening process in which the central area was firstly strengthened, then strengthened in peripheral area. Dynamic contrast-enhanced ultrasound showed characteristic changes in ERM with early and obvious enhancement in the central area and uneven enhancement in the central area. Conclusions:Dynamic contrast-enhanced ultrasonography of ERM lesions has its characteristic changes. The enhancement of the central area of the lesion appeared early and obvious while the surrounding area appeared late and weak, showing the characteristic of "water ripple" concentric circle reinforcement. This enhancement characteristic suggested that ERM skeletal muscle was unevenly damaged and the central area was more obvious.