To investigate the diagnostic value of ultrasound-guided water enema for children with secondary intussusception.

We performed a retrospective analysis of the sonographic findings of 52 children with a confirmed diagnosis of SI through colonoscopy or surgical pathology between May 2016 and May 2019 in Shenzhen Children’s Hospital. The diagnostic value of ultrasound-guided water enema was evaluated.

Of the 52 patients with SI (29 male, 23 female; average age, 50 months [range: 3 months to 12 years]), 16 had intestinal polyps, including 15 cases of juvenile polyps and 1 case of Peutz-Jeghers (P-J) polyps; 14 had Meckel's diverticulum; 11 had lymphoma; 10 had intestinal duplication; and 1 had jejunal schwannoma. All 52 patients were diagnosed with intussusception, of which 41 were confirmed with the presence of pathological lead points (PLPs) before water enema. After enema, PLP was demonstrated in 48 cases. All of the remaining 4 cases without a PLP diagnosis were found to be Meckel’s diverticulum. Ultrasonography revealed the specific features in each category. Patients with juvenile polyps showed hypoechoic masses in the intestinal lumen and some honeycomb-like anechoic masses while the single P-J polyp case showed hypoechoic masses with branching echoes in the intestinal lumen. Three of the Meckel’s diverticula cases showed irregular hyperechoic masses inside the intussusception, and 7 showed cystic masses inside the intussusception. All 11 lymphomas cases showed extremely hypoechoic masses. All 10 intestinal duplication cases showed cystic masses at the neck or inside the intussusception, with walls exhibiting intestinal wall-like structure. The case of jejunal schwannoma showed irregular hypoechoic masses at the neck of the intussusception. There were no major complications such as intestinal perforation occurred in all the children after the completion of water enema ultrasound examination.

Ultrasound-guided water enema helps identify PLPs and improves the diagnosis of primary diseases in children with SI.