| colon | <anatomy> Also called the large intestine. This structure has 6 major divisions: caecum, ascending colon, transverse colon, descending colon, sigmoid colon and rectum. The total length is approximately 5 feet in the adult and it is responsible for forming, storing and expelling waste matter. (27 Sep 1997) |
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| colon ascendens | <anatomy> The first part of the colon (large intestine) that starts in the right lower quadrant of the abdomen and ends at the transverse colon in the right upper quadrant of the abdomen. (27 Sep 1997) |
| colon bacillus | <bacteria> The archetypal bacterium for biochemists, used very extensively in experimental work. A rod shaped gram-negative bacillus (0.5 x 3-5 m) abundant in the large intestine (colon) of mammals. Abbreviation: E. Coli (18 Nov 1997) |
| colon cancer | <oncology> A malignancy that arises from the lining of either the colon or the rectum. Cancers of the large intestine are the second most common form of cancer found in males and females. Symptoms include rectal bleeding, occult blood in stools, bowel obstruction and weight loss. Treatment is based largely on the extent of cancer penetration into the intestinal wall. Surgical cures are possible if the malignancy is confined to the intestine. Risk can be reduced when following a diet which is low in fat and high in fibre. (27 Sep 1997) |
| colon cancer and polyps | Benign tumours of the large intestine are called polyps. Malignant tumours of the large intestine are called cancers. Benign polyps do not invade nearby tissue or spread to other parts of the body. Benign polyps can be easily removed during colonoscopy, and are not life threatening. If benign polyps are not removed from the large intestine, they can become malignant (cancerous) over time. most of the cancers of the large intestine are believed to have developed from polyps. (12 Dec 1998) |
| colon cancer, family history of | Colorectal cancer can run in families. The colon cancer risk is higher if an immediate (first-degree) family member (parents, siblings or children) had colorectal cancer and even higher if more than one such relative had colorectal cancer or if a family member developed the cancer at young age (younger than 55 years). Under any of these circumstances, individuals are recommended to undergo a colonoscopy every three years starting at an age that is 7-10 years younger than when the youngest family member with the cancer wasdiagnosed. For example, if a parent had colon cancer diagnosed at age 50, colonoscopy should start in that person's children at 40-43 years of age. (12 Dec 1998) |
| colon carcinoma | <radiology> Risk factors: colonic adenoma, 93% of colorectal CA arises from adenomatous polyps, 5% of adenomas 5mm in size develop into carcinoma, family history and polyposis syndromes, chronic ulcerative colitis, prominent lymphoid follicular pattern, history of endometrial and breast carcinoma, metastasis: liver (25%); retroperitoneal/mesenteric nodes (15%); hydronephrosis (13%); adrenal (10%); ovary; psoas muscle; ascites, risk of: 1% for synchronous colon carcinoma, 3% for metachronous colon CA, 3.8% for extracolonic malignancy, Dukes A: bowel wall; B: serosa/mesentery; C: lymph nodes; D: metastasis (12 Dec 1998) |
| colon cutoff sign | Radiographic sign of (usually) inflammatory disease preventing distention of the distal transverse colon. (05 Mar 2000) |
| colon descendens | The fourth portion of the large intestine (colon) that communicates with the transverse colon in the left-upper quadrant of the abdomen and the rectum below. (27 Sep 1997) |
| colon obstruction | <radiology> Primary colon carcinoma (70%), diverticulitis (spasm, scarring), volvulus (caecal, sigmoid), inflammatory stricture (IBD, etc.), extrinsic lesion (hernia, neoplasm), faecal impaction, intussusception, Hirschsprung disease, imperforate anus, meconium plug, adhesions, retractile mesenteritis Note: left colon more common, more subacute than SBO (12 Dec 1998) |
| colon pelvinum | <anatomy> The portion of the colon that connects to the descending colon above and the rectum below. (27 Sep 1997) |
| colon sigmoideum | <anatomy> The portion of the colon that connects to the descending colon above and the rectum below. (27 Sep 1997) |
| colon transversum | <anatomy> The third division of the colon (large intestine). It communicates with the ascending colon in the upper right-hand quadrant of the abdomen and the descending colon in the upper left-hand quadrant. (19 Jan 1998) |
| colonalgia | Rarely used term for pain in the colon. Origin: colon + G. Algos, pain (05 Mar 2000) |
| colonialism | The aggregate of various economic, political, and social policies by which an imperial power maintains or extends its control over other areas or peoples. It includes the practice of or belief in acquiring and retaining colonies. The emphasis is less on its identity as an ideological political system than on its designation in a period of history. (webster, 3d ed; from dr. J. Cassedy, nlm history of medicine division) (12 Dec 1998) |
| adenomatous colon polyps | <radiology> Probability of malignancy by size and type Size (cm) less than 1 1-2 greater than 2 --------------------------- tubular 1% 10% 34% mixed (TV) 4% 9% 45% villous 10% 10% 54%, most colon polyps (90%) are hyperplastic (size less than 5 mm) (12 Dec 1998) |
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| arterial arches of colon | Anastomosing branches of the colic arteries that form arch's in the mesocolon from which the walls of the colon are supplied. See: marginal artery of colon. (05 Mar 2000) |
| ascending colon | <anatomy> The first part of the colon (large intestine) that starts in the right lower quadrant of the abdomen and ends at the transverse colon in the right upper quadrant of the abdomen. (27 Sep 1997) |
| bands of colon | teniae coli |
| cancer, colon | A malignant tumour arising from the inner wall of the large intestine. The third leading cause of cancer in males, fourth in females in the U.S. Risk factors for cancer of the colon and rectum (colorectal cancer) include heredity, colon polyps, and long standing ulcerative colitis. most colorectal cancers develop from polyps. Removal of colon polyps can prevent colorectal cancer. Colon polyps and early cancer can have no symptoms. Therefore, regular screening is important. Diagnosis can be made by barium enema or by colonoscopy with biopsy confirmation of cancer tissue. Surgery is the most common treatment for colorectal cancer. (12 Dec 1998) |
| cancer, colon: screening and surveillance | Colon cancer is both preventable and curable. It is preventable by removing precancerous colon polyps. It is curable if early cancer is surgically removed before cancer spread to other parts of the body. Therefore, if screening and surveillance programs were practiced universally, there would be a major reduction in the incidence and mortality of colon cancer. (12 Dec 1998) |
| marginal artery of colon | Artery formed by anastomoses between the right and left colic artery's; it passes downward from the left colic flexure to the aboral end of the pelvic colon. Synonym: artery of Drummond, Riolan's arc. (05 Mar 2000) |
| giant colon | An abnormally large or dilated colon, the condition may be congenital or acquired, acute or chronic. (18 Nov 1997) |
| mesentery of sigmoid colon | See: mesocolon. (05 Mar 2000) |
| mesentery of transverse colon | See: mesocolon. (05 Mar 2000) |
| plica semilunaris of colon | One of the folds of the wall of the colon between sacculations. Synonym: plica sigmoidea, semilunar fold of colon. (05 Mar 2000) |
| muscular coat of colon | Muscular layer of the wall of the colon. Synonym: tunica muscularis coli. (05 Mar 2000) |
| polypsis of the colon | Multiple polyps with a high malignant potential in large bowel. This hereditary condition is also known as polypsis coli and familial adenomatous polyposis. (12 Dec 1998) |
| prediverticular disease of colon | <radiology> Longitudinal and circular muscle thickening with redundancy of folds secondary to myostatic contracture findings: saw tooth sign: crowding and thickening of haustral folds (shortening of colonic segments), superimposed muscle spasm (relieved by antispasmodics) Differential diagnosis: hemmorhage; ischemia; radiation; pseudomembranous colitis see: divericular disease of colon (12 Dec 1998) |
| haustra of colon | <anatomy> The sacculations of the colon, caused by the teniae, or longitudinal bands, which are slightly shorter than the gut so that the latter is thrown into tucks or pouches. Synonym: haustra coli, haustrations of colon, sacculation of colon. (05 Mar 2000) |