ObjectiveTo explore the risk factors of recurrent primary intussusception in children of hydrostaticreduction guided by ultrasonography.MethodsThe clinical data（gender

age

vomiting and bloody stool）and ultrasound images（intussusception location

maximum diameter of intussusception"concentric circle"

blood flow signal of intestinal wall

seroperitoneum and enlarged lymph nodes）of 50 primary intussusception in children were retrospectively analyzed. The riskfactors of recurrent intussusception were screened out by the univariate analysis

and binary Logistic regression equation wasused to analyze the risk factors.The area under the curve and the cut-off value of each factor were calculated by the receiveroperating characteristic（ROC） curve.ResultsUnivariate analysis showed that the maximum diameter of intussusception"concentric circle"

blood stool

seroperitoneum and no blood flow signal of the intestinal wall were the risk factors for theoccurrence of recurrent intussusception（all P<0.05）. Logistic regression analysis revealed that maximum diameter ofintussusception"concentric circle"

bloody stool

seroperitoneum

no blood flow signal of intestinal wall were independent riskfactors for the occurrence of intussusception（OR=5.88

4.20

4.12

3.55）. The cut-off value of maximum diameter ofintussusception"concentric circle"was 35 mm

and the area under ROC curve was 0.97

which had the highest predictiveefficacy.ConclusionThe maximum diameter of intussusception"concentric circle"≥35 mm

blood stool

seroperitoneum andno blood flow signal of intestinal wall are the important risk factors for recurrent primary intussusception in children ofhydrostatic reduction guided by ultrasonography.