Title: Role of Virtual Colonoscopy in the Diagnosis of Colonic Pathologies
Author: Dr P Ramravi Kumar
DOI: https://dx.doi.org/10.18535/jmscr/v8i2.27
Abstract
CT colonography through 128 slice MDCT provides a virtual noninvasive opportunity to visualize the Colon with very good resolution at minimum radiation, in multiple planes in both retrograde and anterograde directions through 3D reconstruction software, hence lumen missed by VC behind the haustral folds can be visualized in the anterograde direction. We in the present study evaluated the ability of virtual colonoscopy to detect colorectal cancers and polyps in suspected patients of colonic pathology Methods: This prospective study was conducted in the Department of Radiology, Prahtima Institute of Medical Sciences, Naganoor, Karimnagar. Patients aged 30 to 80 yrs. complaining of colonic symptoms like constipation, melena, haematochezia, loss of weight and known cases of colonic pathology. All the patients will be given 30 ml heptulac (lactulose) mixed in water at 9 pm the earlier day and put them on NBM overnight which will be followed by rectal enema twice spaced 4 hours and 1 hour before the CT scan. Virtual colonoscopy (CT-VC) examinations will be performed according to a standard protocol. Results: n=32 cases with suspected colonic pathologies n=21 cases had colonic findings forming 65% of the cases with positive colonic findings 48% had some kind of polyps while 29% had carcinoma colon. N=6 cases had carcinoma of the colon among the N=32 cases forming 18.7% of the cases. While 67% percent of the carcinomas were in the distal colon 33% had carcinoma of the proximal colon. Among the 6 cases of carcinoma colon, n=4 cases had advancing carcinoma beyond the colonic wall. Among the n=4 cases 50 percent n=2 cases presented with metastasis to distal organs. Conclusions: Virtual colonoscopy was found to be very useful because of 3D viewing of colon both in forward as well as reverse directions. However, it has limitations because it depends on proper bowel preparation. Electronic bowel cleansing or barium fecal tagging may improve sensitivity. This technique is very useful in elderly patients where sedation is contraindicated and also useful in patients with Diverticulosis where chances of perforation are high by conventional colonoscopy.
Keywords: Virtual Colonoscopy, Colonic Pathologies.
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