A case of renign main pancreatic duct stenosis-the clinical usefulness of intraductal ultrasonography of the pancreas

A 44-year-old man was admitted to our hospital for further examinations of epigastralgia with increased serum amylase. Conventional ultrasonography showed dilatation of the main pancreatic duct (MPD) from the body to the tail of the pancreas. Endoscopic ultrasonography revealed severe localized stenosis of the MPD without tumor. Endoscopic retrograde pancreatography showed severe localized stenosis and dilation of the distal portion of the duct. Peroral pancreatoscopy of the stenosing part of the MPD showed normal mucosa. The diagnosis of benign stenosis of the MPD was made. Partial resection of the body of the pancreas was done due to the history of recurrece of the attack of the pancreatitis. Pathohistological findings revealed chronic pancreatitis. Intraductal sonography of the pancreas (IDUS) (30MHz at frequency) in the postoperative specimen showed hypoechoic band all around the MPD corresponding with periductal fibrosis in the histological sectons. We suggest the usefulness of the IDUS in the diagnosis of the segmental stenosis of the MPD.