Idiopathic Constipation (Differential Diagnosis as before)

Contrast enema in a 5-year-old boy with constipation. X-ray taken after evacuation of contrast. Some contrast still remains in the lower colon ascedens. The thin coating shows a normally wide lumen with a fine structure of the folds in the residual colon. The rectum is enormously dilated with a large and contrast-containing mass. The nearly rounded form of the dilated rectum, the missing involvement of the orally situated sigmoid, and the spotaneous evacuation of most of the contrast do not support Hirschsprung's disease, but idiopathic constipation.