A method is for preparing the appraisal of tomographic colon pictures, in particular of CT or MR pictures of the colon, in the case of which both a manual personal search takes place during which the lesions thus detected are confirmed, and a search for lesions carried out by a computer, if appropriate with automatic preliminary confirmation, takes place, the appraising person also rechecking the computer aided preliminary confirmations. In the method, those lesions that have already been classified as known and confirmed after a comparison with the set of the lesions already detected manually are excluded from the set of the lesions detected with computer assistance and that are to be presented again for personal confirmation.