Intussusception in adults: CT diagnosis

Purpose: Intussusception in adults is nowadays usually diagnosed on computed tomography (CT), as CT is often the first modality for the investigation of prolonged abdominal pain from which these patients suffer. We wish to present the CT, clinical and pathological findings of 16 adult patients with intussusception seen over a 5-year period. Materials and Methods: The abdominal scans of 16 patients with intussusception were reviewed. Special attention was directed to the location of the mass, its shape and fat content, possible underlying pathology and dilatation of the bowel proximally. The findings were correlated with clinical and pathological data. Results: Eight men and eight women, aged 34-81 years, were studied. The most frequent indication for CT was prolonged abdominal pain. CT findings included an inhomogeneous soft tissue mass, target or sausage-shaped, depending on the angle of the CT beam vs. the intussusception, with a fatty component in 14 of the 16. Intussusception was enteroenteric (six), ileocolic (three), or colocolic (seven). Complete small bowel obstruction was present only in one case and some bowel dilatation in three. The underlying pathology could be diagnosed on CT in only two cases of lipoma. Nine patients had an underlying malignant process, eight of them unsuspected. Of the other five, two had coeliac disease, two were classified as idiopathic and one had a necrotic polyp of undetermined pathology. Conclusion: Intussusception on CT presented a characteristic mass lesion containing fat stripes in almost all patients. Obstruction was rarely seen. Malignant lesions were the most common cause and therefore early diagnosis and prompt intervention are essential.