Colorectal Colonoscopy

A series of examinations, including proctoscopy, sigmoidoscopy, colonoscopy, or barium enema, may be necessary to determine the presence of colorectal pathology. 

D. P. Hurlstone and S. S. Cross, Role of aberrant crypt foci detected using high-magnification-chromoscopic colonoscopy in human colorectal carcinogenesis, J. Gastroenterol. Hepatol, 2005, 20, 173. 

A case-control study was designed to explore risk factors for colorectal adenomas. Adenomas are precursors to 80-90% of all colorectal cancers. The study used 236 cases (with adenomas or polyps) and 409 controls (no adenomas) (Tseng ef aF., 1996) (Tabic 11,2). All subjects were patients receiving colonoscopy exams. The subjects were not recruited from the general public, A month or so after the exam, the subjects were asked to fill out a food choice questionnaire. 

Oral sodium picosulfate and oral sodium phosphate have been compared for bowel preparation before elective colorectal surgery and colonoscopy in randomized studies in 256 patients (32). Oral sodium phosphate was superior to sodium picosulfate on surgical assessment of bowel preparation, fecal residue in the resected specimen, and endoscopic score. However, there was no significant difference with regard to abdominal pain, nausea, vomiting, embarrassment, fear, and fatigue between the two groups. 

Yoshioka K, Connolly AB, Ogunbiyi OA, Hasegawa H, Morton DG, Keighley MR. Randomized trial of oral sodium phosphate compared with oral sodium picosulphate (Picolax) for elective colorectal surgery and colonoscopy. Dig Surg 2000 17(l) 66-70. 

Tan JJ, Tjandra JJ Which Is the optimal bowel preparation for colonoscopy - a meta-analysis. Colorectal Dis 2006 8 247-258. 

Colorectal cancer or adenomatous polyps in first-degree relative younger than 60 years or in two or more first-degree relatives at any ages High risk Colonoscopy" Age 40 or 10 years before the youngest case in family, whichever is earlier Every 5-10 years... 

This study is based upon general-population expectations of CRC risk. The use of aspirin may prove more cost effective than colonoscopy when considering patients at inordinately high genetic risk for CRC, such as those patients from HNPCC famihes. Furthermore, since common polymorphisms in drag-metabolizing systems may affect the efficacy of aspirin in colorectal neoplasia prevention," it is possible that these factors can be used to individualize chemopreventive strategies. 

In a retrospective study of 2277 patients who underwent colonoscopy, the correlation between patients laxative use or melanosis coli and colorectal neoplasms was examined. Increases in colorectal adenomas were observed in patients with melanosis coli and in patients with a history of laxative use (Nusko et al. 1993). 

For these and other reasons (i.e., obviously hydrocolonic sonography does not offer the possibility/ opportunity to collect biopsies or remove polyps), although less invasive and expensive than colonoscopy, the use of hydrocolonic sonography, as a screening tool for colorectal cancer, should be evaluated with due care. 

Alhara H, Saito S, Arakava H, Imazu H, Omar S, Raise M, Tajiri H. Comparison of two sodium phosphate tablet-based regimens and a polyethylene glycol regimen for colon cleansing prior to colonoscopy a randomized prospective pilot study. Int J Colorectal Dis 2009 24(9) 1023-30. 

CTC in symptomatic patients is to be considered when colonoscopy can not be completed or carried out this may occur due to mechanical hindrance such as pelvic adhesions, in cases of high risk of perforation as in complicated diverticular disease, when there is an obstruction due to cancer or extracolonic diseases, when the cecum cannot be reached in extreme dolicocolon conditions, or in patients with poor tolerance to colonoscopy in whom heavy sedation may be dangerous (elderly patients or patients with severe co-morbidity). Such indications are similar to those of double contrast barium enema (DCBE) however, CTC has been shown to be both more accurate and better tolerated than DCBE, and should be used preferentially whenever available (Rocket et al. 2005 Taylor et al. 2005 Taylor et al. 2006). Furthermore, in cases of obstructing colonic cancer, CTC is a valuable tool, as it can be conveniently performed at the time of a contrast-enhanced abdominal CT scan for staging purposes to detect synchronous colorectal carcinomas, metas-... 

Ajaj W, Pelster G, Treichel U et al (2003) Dark lumen magnetic resonance colonography comparison with conventional colonoscopy for the detection of colorectal pathology. Gut 52 1738-1743... 

Elwood Ml, Ali G, Schlup MT et al (1995) Flexible sigmoidoscopy or colonoscopy for colorectal screening a randomized trial of performance and acceptability. Cancer Detec... 

Pass R, Do S, Hixson LI (1993) Fatal hyperphosphatemia following Fleet Phospo-Soda in a patient with colonic ileus. Am 1 Gastroenterol 88 929-932 Fenlon HM, Nunes DP, Schroy PC S " et al (1999) A comparison of virtual and conventional colonoscopy for the detection of colorectal polyps. N Engl J Med 341 1496-1503... 

Macari M, Bini EJ, Xue X et al (2002) Colorectal neoplasms prospective comparison of thin-section low-dose multidetector row CT colonography and conventional colonoscopy for detection. Radiology 224 383-392... 

Pickhardt PJ, Taylor AJ (2006) Extracolonic findings identified in asymptomatic adults at screening CT colonography. AJR Am J Roentgenol 186 718-728 Pineau BC, Paskett ED, Chen GJ et al (2003) Virtual colonoscopy using oral contrast compared with colonoscopy for the detection of patients with colorectal polyps. Gastroenterology 125 304-310... 

Schoenfled P, Cash B, Flood A et al (2005) Colonoscopy screening of average-risk women for colorectal neoplasia. N Eng J Med 352 2061-2068... 

Svensson MH, Svensson E, Lasson A et al (2002) Patient acceptance of CT colonography and conventional colonoscopy prospective comparative study in patients with or suspected of having colorectal disease. Radiology... 

Van Gelder RE, Nio CY, Florie J et al (2004b) Computed tomographic colonography compared with colonoscopy in patients at increased risk for colorectal cancer. Gastroenterology 127 41-48... 

Winawer SJ, Stewart ET, Zauber AG et al (2000) A comparison of colonoscopy and double-contrast barium enema for surveillance after polypectomy. National Polyp Study Work Group. N Engl J Med 15 342 1766-1772 Winawer SJ, Fletcher RH, Rex D et al (2003) Colorectal screening and surveillance clinical guidelines rationale-update based on new evidence Gastroenterology 124 544-560... 

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