This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: G.I.T, Subject name: Surgery
True about Ogilvie syndrome are all except 
Select and explain. 
A. It is caused by mechanical obstruction of the colon, B. It involves entire \/ pa of the large colon, C. It occurs after previous surgery, D. It occurs commonly after narcotic use
A: It is caused by mechanical obstruction of the colon
Answer: A: It is caused by mechanical obstruction of the colon 
Explanation: 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.