<unk>  is an abnormal dilation of the colon (also called the large intestine). This leads to hypertrophy of the colon. The dilation is often accompanied by a paralysis of the peristaltic movements of the bowel. In more extreme cases, the feces consolidate into hard masses inside the colon, called fecalomas (literally, fecal tumor), which can require surgery to be removed. A human colon is considered abnormally enlarged if it has a diameter greater than 12 cm in the cecum (it is usually less than 9 cm), greater than 6.5 cm in the rectosigmoid region and greater than 8 cm for the ascending colon. The transverse colon is usually less than 6 cm in diameter. A<unk>  can be either acute or chronic. It can also be classified according to cause.
Megacolon
Fecal impaction
Vesicointestinal fistula
Rectal foreign body
Toxic megacolon
Neutropenic enterocolitis
Defecation
Black stomach