Colonoscopy and m r colonography-a comparative study

Aim: The study was conducted to find out the merits and demerits of standard tool colonoscopy and newer modality Magnetic Resonance Colonography (MRC) in assessing the various colonic pathologies. To find out the role of MRC in patients with obstructive type of colonic lesion were further scope passage was not possible.
Material and Methods: Patients who were attending Medical Gastroenterology Department with clinical diagnosis highly suspicious of colorectal pathology were included in this study. Sixty patients were taken up for study and out of sixty patients thirty patients underwent colonoscopy first then subjected to MR Colonography and another thirty patients were subjected for MR Colonography first then followed by Colonoscopy. Comparative analysis done in assessing various colonic pathology.
Results: Out of sixty patient’s colonoscopy passed up to cecum/ileum in 42 cases (70%). In the remaining 18 (30%) scope not passed up to cecum due to various reasons. MRC revealed additional colonic findings compared to colonoscopy in 5 cases (8.1%). MRC helped in extra colonic findings in 7 cases (11.67%). Comparing MRC with gold standard colonoscopy, both sensitivity (53%) and specificity (67%) is not significantly high for MRC.Both colonoscopy and MRC detects lesion with same accuracy in thirty four patients (57%), colonoscopy detects lesions missed by MRC in twenty one patients (35%) and MRC detects the lesion in five patients (8%), missed by Colonoscopy because of incomplete procedure.
Conclusion: The study suggests MRC is an alternate modality only if colonoscopy is not possible as tissue diagnosis is possible in the later only. The identification of additional lesion at MR colonography signifies the requirement for a second diagnostic approach in the setting of incomplete routine colonoscopy.