Objective To observe conventional ultrasound and contrast-enhanced ultrasound(CEUS)manifestations of Ewing sarcoma(ES)in children.Methods Fifteen children with pathologically confirmed ES were retrospectively collected.Conventional ultrasound and CEUS characteristics of lesions were analyzed.Results Among 15 cases,ES of bone(ESB)was found in 7 cases,while extraskeletal ES(EES)was observed in the other 8 cases.Solitary tumor was noticed in 14 cases,with a median maximum diameter of 7.50 cm,while multiple abdominal masses were found in 1 case.The tumors had irregular shapes and poorly defined boundaries,with medium echogenicity in 7 cases,low echogenicity in 6 cases,while in other 2 cases present as cystic-solid lesions.CDFI showed sparse blood flow in 11 cases,abundant or slightly abundant blood flow in 2 and 1 case,respectively,while no obvious blood flow was observed in 1 case.Rapid high enhancement and rapid washout were found in all 7 cases underwent CEUS,while patchy no-enhancement areas were detected in 4 cases.Conclusion Conventional ultrasonic manifestations of ES had certain specificities,which demonstrated a rapid enhancement and rapid washout pattern during CEUS and may be accompanied by necrosis.

Objective To observe conventional ultrasound and contrast-enhanced ultrasound(CEUS)manifestations of Ewing sarcoma(ES)in children.Methods Fifteen children with pathologically confirmed ES were retrospectively collected.Conventional ultrasound and CEUS characteristics of lesions were analyzed.Results Among 15 cases,ES of bone(ESB)was found in 7 cases,while extraskeletal ES(EES)was observed in the other 8 cases.Solitary tumor was noticed in 14 cases,with a median maximum diameter of 7.50 cm,while multiple abdominal masses were found in 1 case.The tumors had irregular shapes and poorly defined boundaries,with medium echogenicity in 7 cases,low echogenicity in 6 cases,while in other 2 cases present as cystic-solid lesions.CDFI showed sparse blood flow in 11 cases,abundant or slightly abundant blood flow in 2 and 1 case,respectively,while no obvious blood flow was observed in 1 case.Rapid high enhancement and rapid washout were found in all 7 cases underwent CEUS,while patchy no-enhancement areas were detected in 4 cases.Conclusion Conventional ultrasonic manifestations of ES had certain specificities,which demonstrated a rapid enhancement and rapid washout pattern during CEUS and may be accompanied by necrosis.

Atherosclerosis is the main cause of cardiovascular diseases， while Carotid intima-media thickness is a biomarker of subclinical atherosclerosis. Numerous studies have confirmed that exercise can slow down or even reverse the formation and progression of carotid Intima-Media thickness. This paper provides a review of the effects of different exercise modalities， intensities， and populations on the vascular structure to provide a reference for the prevention of atherosclerosis with exercise.