To explore the value of high-frequency ultrasound combined with color Doppler ultrasound in evaluating the blood flow state of intestinal wall in children with intussusception and its predictive effect on the success rate of enema reduction.

A retrospective analysis was conducted to collect clinical data of 293 children with acute intussusception admitted to Northwest Women's and Children's Hospital from January 2022 to December 2024, among them, there were 259 cases in the successful reduction group and 34 cases in the failed reduction group. All patients completed high-frequency ultrasound examination within 2 hours of admission. The concentric circle diameter, sheath diameter, and sleeve sign length were quantitatively measured, and the concentric circle sign, pseudorenal sign, and fluid accumulation were qualitatively observed. The color Doppler ultrasound was simultaneously used to evaluate the intestinal wall blood flow status according to the modified Rubin grading system. All patients received ultrasound-guided air enema reduction treatment. The differences in ultrasound indicators between two groups were compared and the predictive value of single and combined diagnosis for reset failure was analyzed through receiver operating characteristic (ROC) curve.

The concentric circle diameter, sheath diameter, and sleeve sign length in the reduction failure group were significantly greater than those in the reduction success group (P<0.001). The incidences of pseudorenal sign (85.29% vs. 16.60%) and ascites (44.12% vs. 6.18%) in the reduction failure group were significantly higher than those in the reduction success group, while the incidence of concentric circle sign was significantly lower (76.47% vs. 96.91%, P<0.001). The vast majority of children in the reduction success group (73.36%) presented with grade 0 blood flow, whereas the proportions of grade Ⅱ-Ⅳ blood flow signals in the reduction failure group were significantly higher than those in the reduction success group (P<0.001). High-frequency ultrasound combined with color Doppler ultrasound demonstrated excellent diagnostic performance in predicting reduction failure. The sensitivity (94.12%), specificity (97.68%), and Youden index (0.918) of the combined diagnosis were higher than those of high-frequency ultrasound alone or color Doppler ultrasound alone. ROC curve analysis further confirmed that the area under the curve (AUC) of the combined diagnosis (0.962) was significantly greater than that of high-frequency ultrasound alone (0.875) or color Doppler ultrasound alone (0.884) (P<0.05).

High-frequency ultrasound combined with color Doppler ultrasound has important evaluation value for the success rate of intussusception enema reduction by quantifying the morphological characteristics and blood flow state of intestinal wall, and can provide reliable imaging basis for clinical prognosis prediction.