Ultrasonographic findings of small bowel intussusception, focusing on differentiation from ileocolic intussusception

The purpose of this study was to evaluate the typical ultrasonographic findings of transient small bowel intussusception (SBI) and to differentiate it from ileocolic intussusception (ICI) in paediatrics. 22 transient SBI (male:female = 13:9, age: 7-132 months (mean 38 months)) and 27 ICI (male:female = 19:8, age: 1-60 months (mean 13 months)) patients diagnosed on ultrasonography were retrospectively evaluated. The findings of location, diameter, thickness of outer rim, and inclusion of mesenteric lymph nodes within intussuscipiens were compared. In the transient SBI, the head of intussusception was located in the right lower quadrant (RLQ) in 11 (50%), the right upper quadrant (RUQ) in 2 (9.1%) and the periumbilical area in 9 (40.9%) cases. The anteroposterior (AP) diameter ranged from 0.84-2.4 cm (mean 1.38 cm), and thickness of outer rim ranged from 0.10-0.34 cm (mean 0.26 cm). No mesenteric lymph nodes were contained within the intussuscipiens. In the ICI, the head was located in the RUQ in 17 (63%), the epigastrium in 7 (25.9%) and the left upper quadrant in 3 (11.1%) cases. The AP diameter ranged from 1.89-3.32 cm (mean 2.53 cm), and the thickness of the outer rim ranged from 0.30-0.86 cm (mean 0.53 cm). Mesenteric lymph nodes were contained within the intussuscipiens in 26 (96.3%) cases. In conclusion, when compared with ICI, the transient SBI occurs predominantly in the RLQ or periumbilical region, has a smaller AP diameter, a thinner outer rim, and dose not contain mesenteric lymph nodes.