Endosonography in Chronic Pancreatitis - A Comparison Between Endoscopic Retrograde Pancreatography and Endoscopic Ultrasonography

Abstract

Endoscopic ultrasonography (EUS) and endoscopic retrograde pancreatography (ERP) were prospectively performed in 114 patients, 94 of whom (62 men, mean age 53 years) had inflammatory pancreatic disease, either chronic pancreatitis or status post acute edematous pancreatitis. Twenty patients (14 men, mean age 54 years) who were examined for other reasons and who had a normal ERP served as controls. EUS was performed in most cases with the knowledge of ERP results which had been classified according to the Cambridge classification system of chronic pancreatitis as being grade 0 (normal) or 1-3 (inflammatory changes). Parenchymal and ductal changes on EUS were correlated with the ERP changes. Abnormal EUS features were found in all patients with grade 2 and 3 chronic pancreatitis, in 88 % with stage 1, and in 63 % of cases with a normal ERP as well. These changes were, however, not detectable in any of the 20 control cases.

Among the EUS features of chronic pancreatitis, diffuse changes predominated (stage 1: 75 %, 2: 88 %, 3: 96 %) and consisted mainly of alternating echopoor and echorich areas and of a lobulated parenchymal pattern. In 80 % of patients, these findings were combined with an irregular pancreatic margin. Changes of the main pancreatic duct were found in stages 2 and 3 in 81 % and 96 %, respectively; isolated side branch alterations, as detected mainly in stage 1 chronic pancreatitis on ERP, escaped endosonographic visualization. We conclude that EUS shows inflammatory changes in almost all patients in whom ERP suggests chronic pancreatitis. EUS, however, is also positive in a considerable number of cases with normal ERP but who have a clinical episode of pancreatic inflammation. The clinical implication of these findings has to be examined further.