The authors analyzed 177 endoscopic retrograde pancreatograms (ERPs) with normal findings. The complete visualization of the side branches was achieved in 128 patients (72.3%), and aductal zones in the isthmus and mid-body of the pancreas were noted in 49 (27.3%) of these patients. The existence and incidence of the aductal zones were evaluated and verified in 141 anatomical duodenopancreas specimens. Thirty-two corrosion casts and 109 postmortem pancreatograms were analyzed. The postmortem specimens had a 36.2% incidence of aductal zones in the same location, with no statistically significant difference compared with the clinical pancreatograms. The visualization of the side branches was 100% on the postmortem pancreatograms, indicating that the clinical ERCP incidence of aductal zones is realistic.