Double contrast enema and colonoscopy in polyp detection

SUMMARY The diagnostic accuracy of double contrast enema was assessed by colonoscopy of 250 consecutive patients with polypoid lesions that were observed at double contrast enema. The enema method detected 90 % of all existing polypoid lesions, and gave false positive results in less than 3.5° ' Colonoscopy revealed 91 °', of the lesions. Double contrast enema is suitable as a screening procedure and, when used in combination with colonoscopy, only very few polyps will escape detection. The large number of neoplastic polyps detected in this retrospective series emphasises the necessity for a careful radiographic technique combined with colonoscopy to disclose and treat these potentially malignant lesions of the colon.-Since 1954 radiography of the colon according to the double contrast-enema technique, known as the Malm6 method,-3 has been used in our depart-ment on almost 100 000 occasions. The value of the method in the detection of polypoid lesions is well documented.4 13 The first flush of enthusiasm for colonoscopy in the examination of patients for polyps14-21 now appears to be on the wane,68 2224 though colon-oscopy is still regarded as indicated first in the investigation of idiopathic symptoms referable to the colon and for the screening of persons at high risk for carcinoma6 25 26 or with potentially malignant lesions of the colon. The value of radiographic screening for colonic polyps has been seriously questioned by numerous gastroenterologists. In an endeavour to assess the relative diagnostic effectiveness of our routine double contrast radiography we compared the results obtained with this method with those obtained at colonoscopy, rectoscopy, and surgery. Definitions A polyp or polypoid lesion is to be understood as a mass, smaller than 50 mm, arising from the mucous *This work was supported by MFR B79-29X-04819-04