<prompt> A neonate presented with fever, lethargy, abdominal distension, vomiting and constipation. Clinically he was diagnosed as volvulus neonatorum with suspected perforation. Best investigation would be:Plain X-rayBarium enemaUpper GI endoscopyBarium meal follow-through  <response>: a. Plain X-rayRef: Nelsons 20e p 1894-1897, Ghai 8e p 285-286Volvulus neonatorumWhat is it?Intestinal obstruction in a newborn due to twisting of bowel caused by malrotation or non-fixation of colonInvestigationsBarium meal follow-through is the investigation of choice as X-ray is not reliable in early stages of volvulus; However, if perforation is suspected, barium contrast should not be used because of risk of perotinitis 