Ogilvie syndrome

Ogilvie syndrome is the acute dilation of the colon in the absence of any mechanical obstruction in severely ill patients.
Colonic pseudo-obstruction is characterized by massive dilatation of the cecum (diameter > 10 cm) and right colon on abdominal X-ray. It is a type of megacolon, sometimes referred to as "acute megacolon," to distinguish it from toxic megacolon.