Explanation
•A barium enema is generally ordered to confirm the diagnosis. On x-ray film, the barium will outline a narrow, nerveless distal colon with proximal dilation. An abnormal dilation of the colon is called megacolon.
•Hirschprungs’s disease is an absence of ganglionic innervation to the smooth muscle of a section of the bowel. In most instances, this is the lower portion of the sigmoid colon just above the anus. The absence of nerve cells means there are no peristaltic waves at this section to further the passage of fecal material through that segment of intestine. This results in chronic constipation or ribbonlike stools. The portion of the bowel proximal to the obstruction dilates, distending the abdomen.
•Intussusception is an invagination or telescoping of one portion of the intestine into an adjacent portion,causing obstruction.
•In pyloric stenosis, ultrasonography and an upper GI study may reveal delayed gastric emptying, an elongated band thin pylorus or a pyloric mass.