Balloon-catheter endoscopic retrograde pancreatography-compression study for diagnosis of early-stage pancreatitis.

Endoscopic retrograde pancreatography (ERP) is considered by many as the gold standard imaging method in the diagnosis of chronic pancreatitis (CP). However, conventional ERP usually has a limited ability to accurately diagnose early-stage CP, in which only the branch ducts are involved and the main pancreatic duct (MPD) is unaffected. To visualize precisely the branch ducts, we have developed a more sophisticated ERP method, called balloon ERP-compression study (balloon ERP-CS). In this procedure, a catheter equipped with a balloon at its tip is placed first into the MPD via the papilla with the aid of conventional ERP, followed by the removal of the endoscope, leaving the catheter behind. Then, the balloon is inflated, and the contrast medium is injected slowly. The balloon serves to block the back flow of the injected contrast medium from the MPD to the duodenum, enabling visualization of the branch ducts. The compression study affords further precise pancreatography of the corresponding area. Thus, balloon ERP-CS has now become an essential procedure for diagnosis of pancreatic lesions, including CP. So far (April 1984 to April 2005), we have performed the procedure in 1012 cases, for a total of 1562 examinations. In this study, we focus on the role of balloon ERP-CS in diagnosis of early-stage CP to elucidate its characteristic features in association with histological findings. This presentation will clarify the usefulness as well as the limitations of balloon ERP-CS for the diagnosis of CP, especially cases without the involvement of the MPD.