BACKGROUND: Dynamic pancreatography (DP) can establish the development of tissue damage and demonstrate pancreatic necrosis (PN). OBJECTIVE: To prospectively evaluate the usefulness of DP in patients with acute pancreatitis (AP), analyzing its capabilities for determining the incidence of necrosis, and as a prognostic predictor. MATERIAL AND METHODS: All patients with AP seen at our department during 4 years were included. All patients were scheduled to DP. Findings were classified in five groups: I, interstitial AP; II, secondary fluid collections; III, peripancreatic necrosis; IV, pancreatic necrosis < 50% and pancreatic necrosis > 50%. Also included for analysis were: demographic variables, etiology, APACHE-II score, and Ranson's signs; when infection was suspected, cultures were done. PD and operative findings were correlated to calculate sensibility (S), specificity (Sp), positive and negative predictive values (PPV, NPV), and the diagnostic accuracy (DA) of the test. Correlation between severity/mortality and morphologic alterations according to the classified group were also performed. RESULTS: 244 patients. Biliary associated pancreatitis in 47% and alcohol induced in 37%. DP in 207 patients showed, 34 patients in group I; 36 in group II, 67 in group III, 47 and 60 in groups IV and V, respectively. Secondary pancreatic infection was present in 48%. One hundred seventy-two patients underwent surgery; the surgical indication was to interrupt the pathogenesis of complications in 52%. DP correlated with the prognostic signs and APACHE-II score as predictors of complications with an overall (S) of 93%, (Sp) 98%, (PPV) 91%, (NPV) 98%, and (DA) 97%. Greater scores values are all directly proportional with PD necrosis findings (P < 0.05). There was not PD related morbidity. CONCLUSIONS: We found correlation between PD classification and prognostic factors. Morphologic alterations were accurately identified. PD as preoperative work-up allows surgeons design operative strategies and as is useful follow-up of the patients after necrosectomy.