[Tomodensitometry of severe acute pancreatitis]

90 computed tomographic examinations were performed to 57 patients referred at Hospital Saint-Louis for an acute pancreatitis. 32 patients were operated or autopsied. Among these 32 patients, 19 patients had 21 examinations before surgery or autopsy; the other 13 patients had their computed tomographic examinations after one or more surgical procedures. During a severe acute pancreatitis the pancreas is always large either locally or diffusely. A pancreatic reaction is visible around and possibly at distance of the pancreas. When extraluminal gas is visible (3/5) it signifies gangrenous pancreatitis but it is necessary to eliminate a digestive fistulous tract and/or a communication between a pseudocyst and the digestive tract. Except gangrenous it is not possible to precise the nature of pancreatic reaction. The diagnosis of pseudocyst was easy 9/10, difficult 1/10; we did a false positive diagnosis of pseudocyst. Computed tomography and ultrasounds were compared in ten patients for the search of gallbladder lithiasis. Computed tomography can show large and small (2/4) biliary calculus in the gallbladder that cannot be shown by ultrasounds. A normal pancreas in a normal retroperitoneal space exclude the diagnosis of a severe acute pancreatitis. CT aspects of acute pancreatitis must be considered as a good diagnostic test of an acute pancreatitis.