The clinical significance of the pancreas divisum W. Rosch, H. Koch, O. Schaffner, L. Demling,
MD MD MD MD
Erlangen, Germany
Endoscopists are well advised to be familiar with the ontogenic variants in the pancreas and its duct system. Of particular importance is the anomaly of "pancreas divisum" that can be marked by isolated pancreatitis. Increasing experience in retrograde pancreatography shows an extraordinarily broad variability in the shape of the pancreatic duct and the anatomy of the Vaterian papilla with 1, 2, or 3 openings.] In about 25% of all cannulations 2 papillas are seen where, by definition, Wirsung's duct ends in the major papilla and Santorini's duct ends in the minor papilla.' The variety of anatomical findings is based on the ontogenic development. At the end of the second fetal month a ventral and a dorsal anlage fuse into a single organ. The main portion of the gland including the superior anterior part of the head, the body, and the tail is formed by the dorsal anlage which was originally drained by Santorini's duct. The minor ventral anlage forming the posterior and inferior part of the head flows together with the common bile duct into the major papilla. However, with the fusion of the organ the ductal system of the minor ventral anlage becomes the main pancreatic duct, whereas the ductal system of the dorsal anlage is obliterated in most patients and no longer communicates with the duodenum. There may be a developmental arrest at any stage causing multiform ductal variations (Table f). The most important of these varieties is the complete separation of both ductal systems in a grossly undivided gland (pancreas divisum). In over 1850 successful cannulations of Vater's papilla, 63 cases of pancreas divisum (3.4%) were encountered. The endoscopist performing retrograde pancreatography should be familiar with this finding. Usually in the case of a divided pancreas a small ductal system appears simultaneously with the common bi Ie duct. However, this gland may be so tiny that it is easily overlooked. Our smallest ventral pancreas had a diameter of less than 1 em. The radiologist observing the instillation of contrast material into the pancreatic duct should
therefore look for a small duct which branches off at a short distance from the papilla into minute ramifications. This is the only way to avoid parenchymography, inasmuch as only 1 or 2 ml of contrast medium suffice to stain the whole organ and increase the risk of an iatrogenic acute pancreatitis considerably' (Figure 1a). In only somewhat less than onethird of all patients the cannulation of the minor papilla was successful. In part this was due to its localization on the superior and (compared to the major papilla) more dorsal aspect of the duodenum and in part to the minute opening. A simultaneous filling of both ductal systems by rapid intubation of both papillae was possible in only 2 patients (Figure 1b). Of our 63 patients, 50 exhibited a normal pancreas divisum. In 13 patients, however, pathologic findings were seen, thus stressing the importance of a trial to cannulate also the minor papilla when chronic pancreatitis or pancreatic tumor are suspected on clinical grounds. In 5 patients an isolated pancreatitis of Wirsung's duct was diagnosed, in 4 patients only Santorini's duct showed pathological changes, and in 3 patients both anlagen were deformed by pancreatitic alterations. Table I. Types of ductal configuration based on ontogenesis
according to Keyl> Type 1: separate ductal systems corresponding to the ventral and dorsal anlage (pancreas divisum) Type 2: fusion of the ductal systems; the duct of the dorsal anlage is the main duct Type 3: the main duct becomes the ventral duct, whereas Santorini's duct increases in size Type 4: Santori ni'sduct no longer communicates with the duodenum Type 5: there is only one ductal system, viz., Wirsung's duct
From the Department of Internal Medicine, University of Erlangen-Nuremberg, Erlangen, Germany. Reprint requests: Dr. med. W. Rosch, Medizinische Universitatsklinik, 0 - 852 Erlangen, Krankenhausstr. 12, West Germany. 206
GASTROINTESTINAL ENDOSCOPY
In 1 patient a tumorous obstruction of the dorsal anlage (Santorini's duct) was seen, whereas Wirsung's duct was essentially normal. Most of these findings were confirmed at operation. In case of an isolated chronic pancreatitis of Santorini's duct (Figure 2a), the surgeon is faced with the problem that no connective tissue septum separates the 2 portions of the gland. Whereas in this condition subtotal pancreatectomy is indicated, leaving a fairly normal inferior head portion behind, in cases of an isolated pancreatitis of Wirsung's duct (Figure 2b), Whipple's procedure may be indicated insofar as the body and tail of the gland are drained by Santorini's duct without pancreatitic changes.
DISCUSSION The finding of isolated pancreatitis in a divided pancreas bears on the current views of the pathogenesis of chronic pancreatitis. In case of an isolated pancreatitis of Santorini's duct, the reflux of bile or a spreading inflammation from the biliary system can be ruled out since no communication exists with the common bile duct. In isolated pancreatitis of Wirsung's duct, metabolic disorders or toxic effect, such as by alcohol, are very unlikely when the other ductal system is normal. Several of our patients with isolated pancreatitis of Santorini's or Wirsung's duct where chronic alcoholics. The clinical significance of the pancreas divisum lies in the danger of overinstillation of contrast medium to get a staining beyond a suspected ductal obstruction, thereby inducing acute pancreatitis. Only careful observation of the branching of Wirsung's duct can avoid this complication. On the other hand, a normal ventral anlage does not rule out chronic pancreatitis in the glandular portion drained by Santorini's duct. Cannulation also of the minor papilla should be attempted in all patients whose clinical symptoms lead to suspicion of a pancreatic disorder.
REFERENCES
Figure 1. (a) Pancreas divisum (ventral anlage) with common bile duct. (b) Simultaneous filling of Wirsung's and Santorini's ducts in a case of pancreas divisum.
1. COTTON PB: Cannulation of the papilla of Vater by endoscopy and retrograde cholangio-pancreatography. Gut 13:1014, 1972 2. KEYl R: lJber die Beziehungen des Santorinischen Ganges zum Zwiiffingerdarm und zum Wirsungschen Gang. Gegenb morph Jb 55 :345, 1926 3. PHILLIP], KOCH H, CLASSENM: Variations and anomalies of the papilla of Vater, the pancreas and the biliary system. Endoscopy 6:70, 1974 4. RUPPIN H, AMON R, EnL W, CLASSEN M, KOCH H, DEMLING L: Akute Pancreatitis nach endoskopischer Pancreatographie, in Fortschritte der Endoskopie, H. lindner, Witzstrock, Baden-Baden, 1974
Figure 2. (a) Isolated chronic pancreatitis affecting Santorini's duct with normal ventral pancreas. (b) Isolated chronic pancreatitis affecting Wirsung's duct (confirmed at operation). VOLUME 22, NO.4, 1976
207
MD MD MD MD
Erlangen, Germany
Endoscopists are well advised to be familiar with the ontogenic variants in the pancreas and its duct system. Of particular importance is the anomaly of "pancreas divisum" that can be marked by isolated pancreatitis. Increasing experience in retrograde pancreatography shows an extraordinarily broad variability in the shape of the pancreatic duct and the anatomy of the Vaterian papilla with 1, 2, or 3 openings.] In about 25% of all cannulations 2 papillas are seen where, by definition, Wirsung's duct ends in the major papilla and Santorini's duct ends in the minor papilla.' The variety of anatomical findings is based on the ontogenic development. At the end of the second fetal month a ventral and a dorsal anlage fuse into a single organ. The main portion of the gland including the superior anterior part of the head, the body, and the tail is formed by the dorsal anlage which was originally drained by Santorini's duct. The minor ventral anlage forming the posterior and inferior part of the head flows together with the common bile duct into the major papilla. However, with the fusion of the organ the ductal system of the minor ventral anlage becomes the main pancreatic duct, whereas the ductal system of the dorsal anlage is obliterated in most patients and no longer communicates with the duodenum. There may be a developmental arrest at any stage causing multiform ductal variations (Table f). The most important of these varieties is the complete separation of both ductal systems in a grossly undivided gland (pancreas divisum). In over 1850 successful cannulations of Vater's papilla, 63 cases of pancreas divisum (3.4%) were encountered. The endoscopist performing retrograde pancreatography should be familiar with this finding. Usually in the case of a divided pancreas a small ductal system appears simultaneously with the common bi Ie duct. However, this gland may be so tiny that it is easily overlooked. Our smallest ventral pancreas had a diameter of less than 1 em. The radiologist observing the instillation of contrast material into the pancreatic duct should
therefore look for a small duct which branches off at a short distance from the papilla into minute ramifications. This is the only way to avoid parenchymography, inasmuch as only 1 or 2 ml of contrast medium suffice to stain the whole organ and increase the risk of an iatrogenic acute pancreatitis considerably' (Figure 1a). In only somewhat less than onethird of all patients the cannulation of the minor papilla was successful. In part this was due to its localization on the superior and (compared to the major papilla) more dorsal aspect of the duodenum and in part to the minute opening. A simultaneous filling of both ductal systems by rapid intubation of both papillae was possible in only 2 patients (Figure 1b). Of our 63 patients, 50 exhibited a normal pancreas divisum. In 13 patients, however, pathologic findings were seen, thus stressing the importance of a trial to cannulate also the minor papilla when chronic pancreatitis or pancreatic tumor are suspected on clinical grounds. In 5 patients an isolated pancreatitis of Wirsung's duct was diagnosed, in 4 patients only Santorini's duct showed pathological changes, and in 3 patients both anlagen were deformed by pancreatitic alterations. Table I. Types of ductal configuration based on ontogenesis
according to Keyl> Type 1: separate ductal systems corresponding to the ventral and dorsal anlage (pancreas divisum) Type 2: fusion of the ductal systems; the duct of the dorsal anlage is the main duct Type 3: the main duct becomes the ventral duct, whereas Santorini's duct increases in size Type 4: Santori ni'sduct no longer communicates with the duodenum Type 5: there is only one ductal system, viz., Wirsung's duct
From the Department of Internal Medicine, University of Erlangen-Nuremberg, Erlangen, Germany. Reprint requests: Dr. med. W. Rosch, Medizinische Universitatsklinik, 0 - 852 Erlangen, Krankenhausstr. 12, West Germany. 206
GASTROINTESTINAL ENDOSCOPY
In 1 patient a tumorous obstruction of the dorsal anlage (Santorini's duct) was seen, whereas Wirsung's duct was essentially normal. Most of these findings were confirmed at operation. In case of an isolated chronic pancreatitis of Santorini's duct (Figure 2a), the surgeon is faced with the problem that no connective tissue septum separates the 2 portions of the gland. Whereas in this condition subtotal pancreatectomy is indicated, leaving a fairly normal inferior head portion behind, in cases of an isolated pancreatitis of Wirsung's duct (Figure 2b), Whipple's procedure may be indicated insofar as the body and tail of the gland are drained by Santorini's duct without pancreatitic changes.
DISCUSSION The finding of isolated pancreatitis in a divided pancreas bears on the current views of the pathogenesis of chronic pancreatitis. In case of an isolated pancreatitis of Santorini's duct, the reflux of bile or a spreading inflammation from the biliary system can be ruled out since no communication exists with the common bile duct. In isolated pancreatitis of Wirsung's duct, metabolic disorders or toxic effect, such as by alcohol, are very unlikely when the other ductal system is normal. Several of our patients with isolated pancreatitis of Santorini's or Wirsung's duct where chronic alcoholics. The clinical significance of the pancreas divisum lies in the danger of overinstillation of contrast medium to get a staining beyond a suspected ductal obstruction, thereby inducing acute pancreatitis. Only careful observation of the branching of Wirsung's duct can avoid this complication. On the other hand, a normal ventral anlage does not rule out chronic pancreatitis in the glandular portion drained by Santorini's duct. Cannulation also of the minor papilla should be attempted in all patients whose clinical symptoms lead to suspicion of a pancreatic disorder.
REFERENCES
Figure 1. (a) Pancreas divisum (ventral anlage) with common bile duct. (b) Simultaneous filling of Wirsung's and Santorini's ducts in a case of pancreas divisum.
1. COTTON PB: Cannulation of the papilla of Vater by endoscopy and retrograde cholangio-pancreatography. Gut 13:1014, 1972 2. KEYl R: lJber die Beziehungen des Santorinischen Ganges zum Zwiiffingerdarm und zum Wirsungschen Gang. Gegenb morph Jb 55 :345, 1926 3. PHILLIP], KOCH H, CLASSENM: Variations and anomalies of the papilla of Vater, the pancreas and the biliary system. Endoscopy 6:70, 1974 4. RUPPIN H, AMON R, EnL W, CLASSEN M, KOCH H, DEMLING L: Akute Pancreatitis nach endoskopischer Pancreatographie, in Fortschritte der Endoskopie, H. lindner, Witzstrock, Baden-Baden, 1974
Figure 2. (a) Isolated chronic pancreatitis affecting Santorini's duct with normal ventral pancreas. (b) Isolated chronic pancreatitis affecting Wirsung's duct (confirmed at operation). VOLUME 22, NO.4, 1976
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