Transient intussusception – What the sonographer needs to know

Intussusception is typically considered an acute emergency; however, the increased utilisation of medical imaging has revealed that intussusceptions can also be transient, asymptomatic and possibly physiologic. Sonographers should be aware of three categories of intussusceptions: (i) persistent intussusceptions resulting in acute abdomen and requiring urgent intervention, (ii) transient symptomatic intussusceptions which may be amenable to a ‘wait-and-see’ strategy and (iii) transient asymptomatic intussusceptions which almost always involve the small bowel. In particular, the incidental discovery of enteroenteric intussusceptions in children should not be confused with acute pathology. In adults, sonographers should be mindful of the frequent presence of pathological lead points and further investigations may be warranted. In this literature review, we provide an overview of transient intussusceptions, highlight important differences between children and adults and describe sonographic appearances of various intussusceptions and their mimics.