Slight Enlargement of the Head of the Pancreas: Associated Pathologic Changes in the Duodenum

Abstract

RECENTLY, the radiologic demonstration of slight enlargement of the head of the pancreas has been brought to our attention (1, 2, 3). Previously, the radiologic diagnosis of pancreatic disease was made only in late instances, when the excessive enlargement of the head of the pancreas had produced signs of pressure against the adjacent viscera. Because of the position of the pancreas, especially its relation to the concave aspect of the duodenum, and the greater curvature of the pylorus, pressure defects are usually observed when the tumor mass has attained a large size. Since the majority of pancreatic lesions involve the head, and its close relationship with the ampullary portion of the duodenum, recent roentgenologic advances are now more likely to disclose some abnormality in this segment at an earlier period than has heretofore been possible. The roentgenologic changes in the muroentgen picture in three necropsy cases. Recently we have observed two cases which clearly demonstrated the characteristic type of pressure-filling defect in the ampullary portion of the duodenum produced by slight enlargement of the head of the pancreas. The radiologic criteria for the diagnosis of minimal enlargement of the head of the pancreas are as follows: (1) an inverted figure 3 pressure-filling defect in the ampullary portion of the duodenum; (2) two small depressions of smooth contour, well defined, produced by pressure of the enlarged head, with a small nipple-like projection between the two depressions, which represents the papilla; (3) distortion of Kerkring's folds; (4) displacement of surrounding mucosa; piling up of mucosal folds; (5) changes in contour of the ampullary portion of the duodenum. The defective ampullary segment of the duodenum is constantly visible in serial cosal configuration and contour of the ampullary portion of the duodenum offers a new field for the diagnosis of intrinsic and extrinsic pathology affecting this segment of the intestine. Scant attention has been directed to the importance of the minute examination of the ampullary portion of the duodenum. It must be emphasized that other changes might be present as an accompanying phenomenon which cannot at this time be interpreted. A study of the early changes of the mucosa and configuration of the ampullary portion of the duodenum merits, therefore, considerable study. Frostberg, in 1938, called attention to a new roentgen sign, produced by slight enlargement of the head of the pancreas, and demonstrated a characteristic roentgenograms, although we find that it may be demonstrated in only a few films of a large series. Its demonstration depends, to some extent, upon the angle at which the roentgenogram is made. The constancy of the defect also depends upon the amount of pressure and extent of filling of the duodenum. The sign is best observed on films made in the prone position, but, at times, is also observed on those made in the oblique position.