Clinical and Ultrasonographic Features of Secondary Intussusception in Children

The aim of this study was to review the ultrasonographic features of secondary intussusception (SI) in children and assess the value of ultrasound in the diagnosis of pediatric SI. The authors performed a retrospective analysis on the ultrasound findings of 1977 cases of primary intussusception (PI) and 37 cases of SI in children. The SI cases were diagnosed by ultrasonography and confirmed by laparotomy or histopathologic diagnosis. The clinical and ultrasonographic features were analyzed and compared between these two groups. The age, no flatus or defecation, position, diameter and length of intussusception, the presence of free intraperitoneal liquid, and intestinal dialation at the proximal end present, all contributed to the differentiation between PI and SI (all P < 0.05). Ultrasound was able to demonstrate the pathological lead point (PLP) shadows in all of the 37 SI cases, either in the cervical part or intussusceptum of the intussusception. Among the 37 SI patients, 21 cases (56.8 %) were accurately categorized with lesions, including intestinal polyps, cystic intestinal duplication, intestinal wall lymphoma, and a small part of Meckel's diverticulum. Ultrasound can be used as a feasible and effective method to discriminate PI from SI. Once the PLP is detected, a definite diagnosis can be made. • The clinical and ultrasonographic features were compared between SI and PI. • The age, location, diameter and length of intussusception, and intestinal dilation were distinguishing features. • The causes of SI were found to be polyps, intestinal duplication, lymphoma, and Meckel's diverticulum. • Ultrasound can be used as an important method to diagnose SI. • Demonstration and confirmation of PLP are vital to diagnosing SI.