Adult intussusception: diagnosis and clinical relevance.

Intussusception is relatively rare in the adult population and differs substantially from pediatric intussusception. Most adult intussusceptions identified at surgery are caused by a definable structural lesion, a substantial proportion of which are malignant, particularly in the colon. Small bowel intussusceptions, however, have a lower prevalence of malignancy. Diagnosis of adult intussusception can be made reliably with noninvasive imaging techniques. CT is now widely regarded as the modality of choice for diagnosing intussusception in adults, but ultrasound and MR imaging have also been used effectively. Determination of the presence of a malignant lead point remains problematic because an edematous or hemorrhagic intussuscipiens may mimic a mass on each modality. Markers for bowel viability have been described but are not precise. Treatment of the persistent symptomatic intussusception in which neoplasia is suspected is surgical, and preoperative reduction is contraindicated. Transient relatively asymptomatic enteric intussusceptions discovered by imaging may not require intervention.