Introduction
Background
Pancreas divisum, the most common congenital variant of the pancreatic anatomy, occurs when the ductal systems of the ventral and dorsal pancreatic ducts fail to fuse. As a result of nonunion of the ducts, a major portion of pancreatic exocrine secretions enter the duodenum via the dorsal duct and minor papilla. Generally, it has been accepted that a relative obstruction to pancreatic exocrine secretory flow through the minor duct and minor papilla can result in pancreatitis in a small number of patients with pancreas divisum (with stenotic minor papilla). Incomplete or partial divisum is defined as the communication of the dorsal and ventral ducts via a tiny branch. See the images below.
Computed tomography (CT) scan of a patient with pancreas divisum. Sequential axial CT images demonstrate separate pancreatic ducts of Santorini and Wirsung to the region of the minor and major ampulla, respectively.
CT scan of a patient with pancreas divisum. Sequential axial CT images demonstrate separate pancreatic ducts of Santorini and Wirsung to the region of the minor and major ampulla, respectively. Note that the pancreatic duct of Santorini is located anterior to the intrapancreatic portion of the common bile duct.
Magnetic resonance cholangiopancreatography (MRCP) of a patient with pancreas divisum. The pancreatic duct of Santorini and the common bile duct are visualized. (Courtesy of Glenn Krinsky, MD)
Recent studies
Borak et al assessed the long-term outcomes of endoscopic minor papilla therapy (MPE) in symptomatic patients with pancreas divisum. The patients were divided into 3 groups: (1) acute recurrent pancreatitis, (2) chronic pancreatitis, and (3) chronic/recurrent epigastric pain. Primary success rates were 53.2% for acute recurrent pancreatitis, 18.2% for chronic pancreatitis, and 41.4% for chronic/recurrent epigastric pain. Secondary success rates (2 or fewer additional ERCPs) were 71.0% for acute recurrent pancreatitis, 45.5% for chronic pancreatitis, and 55.2% for chronic/recurrent epigastric pain. Younger age and chronic pancreatitis were independently associated with a lower success rate.1
Chacko et al studied the use of minor papilla endotherapy (MPE) in 57 pancreas divisum patients with recurrent acute pancreatitis (RAP) (n = 27), abdominal pain and chronic pancreatitis (CP) (n = 20), abdominal pain alone (n = 8), or other related factors (n = 2). MPE was considered successful in 49 of the 57 patients (86%). In 12 of the 57 patients (21%), 16 additional interventions were required because of incomplete response (celiac plexus block [4], intrathecal narcotic pump [2], sphincteroplasty [7], bilateral thoracic splanchnicectomy [2], and Puestow procedure [1]). The authors found that MPE is most effective in patients with pancreas divisum who have recurrent acute pancreatitis (RAP) with or without pancreatic ductal changes. They noted that although patients with chronic pain and pancreas divisum respond poorly to MPE, the majority will have clinical improvement after additional nonendoscopic interventions for pain management.2
Pathophysiology
Most people with anomalous pancreatic ductal systems are asymptomatic and completely unaffected by the condition; however, a significant number of patients present with recurrent attacks of acute pancreatitis. A relative obstruction to the flow of pancreatic fluid at the level of an inadequately patent or stenosed minor papilla has been hypothesized to result in an increase in intraductal pressure with consequent pancreatitis.
In patients with pancreas divisum, pancreatic history has demonstrated changes of chronic pancreatitis in the dorsal duct distribution and normal parenchyma in the ventral duct distribution. The etiology of stenosis of the accessory papilla is not identical to that of the clinical entity of stenosis or papillitis of the ampulla of Vater. Relative stenosis of the minor sphincter is believed to occur because, as an outlet, it is too small to accept the exocrine drainage secretions from most of the adult pancreas. The slowly developing resistance to increased ductal pressure as the pancreas grows ultimately cannot be tolerated and pancreatitis ensues.
Frequency
International
Pancreas divisum is observed in 6% of normal persons at autopsy. The frequency with which pancreas divisum has been diagnosed during a patient’s lifetime has increased with newer diagnostic modalities.
Mortality/Morbidity
An incidence of pancreas divisum as high as 10-20% has been reported in some series in patients with acute recurrent pancreatitis. The actual incidence of divisum and minor papilla stenosis is not known, but it is certainly significantly less than that of pancreas divisum alone.
Race
No racial predominance exists, although the anomaly has been noted more frequently in whites.
Sex
Themale-to-female ratio is 1:1.
Age
Age ranges from 7 months to 98 years, with a median age at diagnosis of 57 years.
Anatomy
The pancreas is formed during the embryologic stage from distinct ventral and dorsal buds, which arise from the duodenal diverticulum. The ventral duct undergoes rotation and fuses with the dorsal duct by the seventh week of intrauterine life.
In 1642, Wirsung demonstrated the main pancreatic duct, and in 1775, Santorini accurately described the ductal anatomy and demonstrated the accessory pancreatic duct.
Typically, the main pancreatic duct is derived from both embryologic parts of the pancreas; the dorsal pancreas provides the main duct in the tail and body of the gland, and the ventral pancreas provides the main duct in the head of the gland. The accessory duct (called the duct of Santorini) is the remaining portion of the duct in the dorsal pancreas and may drain through an accessory papilla more proximally in the duodenal loop.
In pancreas divisum, the ventral and dorsal pancreatic ducts fail to fuse in utero, resulting in drainage of the bulk of pancreatic fluid (80-95%) via the duct of Santorini through the relatively small minor papilla.
Presentation
The symptom complex of patients with pancreas divisum and minor papilla stenosis includes abdominal pain of varying intensity, with epigastric pain radiating to the back and pain brought on by alcohol intake and worsened by eating fatty foods. Patients usually present with nausea, vomiting, weight loss, diarrhea, and jaundice (which can be both obstructive and nonobstructive). Many patients are treated for gastritis, irritable bowel syndrome, or other conditions before a more definitive investigation for a pancreatic abnormality.3,4,5
Patients usually present with an increased serum amylase level, lipase level, bilirubin level, white blood cell count, or urinary amylase-to-urinary creatinine ratio.
Preferred Examination
Take a methodical approach to the patient with recurrent abdominal pain and pancreas divisum. The presence of clear-cut pancreatitis in association with this anomaly on presentation makes it easier to determine whether the pancreas is the site of origin of the abdominal pain. In patients with divisum who do not demonstrate clinical pancreatitis, determine the existence of accessory papilla stenosis. Some patients may demonstrate focal dilatation of the pancreatic duct at the minor ampulla (termed santorinicele).6,7
Endoscopic retrograde cholangiopancreatography (ERCP) is the test of choice for making a diagnosis of pancreas divisum. Occasionally, this anomaly can be depicted with computed tomography (CT), but CT has a low sensitivity and requires thin slices. Magnetic resonance pancreatography (with or without secretin) may replace ERCP for diagnostic purposes in the future.
Limitations of Techniques
ERCP is expensive and invasive, with a reported complication rate of 5%.
The use of secretin increases the cost of MRI examination because of the cost of the drug and the additional imaging time.
Differential Diagnoses
Choledochal Cyst
Pancreas, Adenocarcinoma
Pancreatitis, Acute
Pancreatitis, Chronic
Other Problems to Be Considered
Annular pancreas
More on Pancreas Divisum |
 Overview: Pancreas Divisum |
| Imaging: Pancreas Divisum |
| Follow-up: Pancreas Divisum |
| Multimedia: Pancreas Divisum |
| References |
| Further Reading |
| Next Page » |
References
Borak GD, Romagnuolo J, Alsolaiman M, Holt EW, Cotton PB. Long-term clinical outcomes after endoscopic minor papilla therapy in symptomatic patients with pancreas divisum. Pancreas. Nov 2009;38(8):903-6. [Medline].
Chacko LN, Chen YK, Shah RJ. Clinical outcomes and nonendoscopic interventions after minor papilla endotherapy in patients with symptomatic pancreas divisum. Gastrointest Endosc. Oct 2008;68(4):667-73. [Medline].
Alazmi WM, Mosler P, Watkins JL, et al. Predicting pancreas divisum by inspection of the minor papilla: a prospective study. J Clin Gastroenterol. Apr 2007;41(4):422-6. [Medline].
Spicak J, Poulova P, Plucnarova J, et al. Pancreas divisum does not modify the natural course of chronic pancreatitis. J Gastroenterol. Feb 2007;42(2):135-9. [Medline].
Ng WK, Tarabain O. Pancreas divisum: a cause of idiopathic acute pancreatitis. CMAJ. Apr 28 2009;180(9):949-51. [Medline].
Kamisawa T, Egawa N, Tu Y, et al. Pancreatographic investigation of embryology of complete and incomplete pancreas divisum. Pancreas. Jan 2007;34(1):96-102. [Medline].
Liao Z, Gao R, Wang W, Ye Z, Lai XW, Wang XT, et al. A systematic review on endoscopic detection rate, endotherapy, and surgery for pancreas divisum. Endoscopy. Mar 31 2009;[Medline].
Zeman RK, McVay LV, Silverman PM, et al. Pancreas divisum: thin-section CT. Radiology. Nov 1988;169(2):395-8. [Medline].
Bret PM, Reinhold C, Taourel P, et al. Pancreas divisum: evaluation with MR cholangiopancreatography. Radiology. Apr 1996;199(1):99-103. [Medline].
Gullo L, Lucrezio L, Calculli L, Salizzoni E, Coe M, Migliori M, et al. Magnetic resonance cholangiopancreatography in asymptomatic pancreatic hyperenzymemia. Pancreas. May 2009;38(4):396-400. [Medline].
Chalazonitis NA, Lachanis BS, Laspas F, Ptohis N, Tsimitselis G, Tzovara J. Pancreas divisum: magnetic resonance cholangiopancreatography findings. Singapore Med J. Nov 2008;49(11):951-4; quiz 955. [Medline].
De Filippo M, Calabrese M, Quinto S, Rastelli A, Bertellini A, Martora R, et al. Congenital anomalies and variations of the bile and pancreatic ducts: magnetic resonance cholangiopancreatography findings, epidemiology and clinical significance. Radiol Med. Sep 2008;113(6):841-59. [Medline].
Manfredi R, Costamagna G, Brizi MG, et al. Severe chronic pancreatitis versus suspected pancreatic disease: dynamic MR cholangiopancreatography after secretin stimulation. Radiology. Mar 2000;214(3):849-55. [Medline].
Warshaw AL, Simeone JF, Schapiro RH, Flavin-Warshaw B. Evaluation and treatment of the dominant dorsal duct syndrome (pancreas divisum redefined). Am J Surg. Jan 1990;159(1):59-64; discussion 64-6. [Medline].
Dawson W, Langman J. An anatomical-radiological study on the pancreatic duct pattern in man. Anat Rec. Jan 1961;139:59-68. [Medline].
Delhaye M, Engelholm L, Cremer M. Pancreas divisum: congenital anatomic variant or anomaly? Contribution of endoscopic retrograde dorsal pancreatography. Gastroenterology. Nov 1985;89(5):951-8. [Medline].
Ertan A. Long-term results after endoscopic pancreatic stent placement without pancreatic papillotomy in acute recurrent pancreatitis due to pancreas divisum. Gastrointest Endosc. Jul 2000;52(1):9-14. [Medline].
Gregg JA. Pancreas divisum: its association with pancreatitis. Am J Surg. Nov 1977;134(5):539-43. [Medline].
Madura JA. Pancreas divisum: stenosis of the dorsally dominant pancreatic duct. A surgically correctable lesion. Am J Surg. Jun 1986;151(6):742-5. [Medline].
Further Reading
Related eMedicine topics
Pancreatic Divisum (from Gastroenterology)
Pancreatitis
Pancreatitis, Acute (from Radiology)
Pancreatitis, Chronic (from Radiology)
Pancreatitis, Acute (from Gastroenterology)
Clinical guidelines
ASGE Guideline: The Role of ERCP in Diseases of the Biliary Tract and the Pancreas
AGA Institute Medical Position Statement on Acute Pancreatitis
Clinical trials
EUROPAC-2 - Pain Treatment of Hereditary and Idiopathic Pancreatitis
Diclofenac for the Prevention of Post-ERCP Pancreatitis in Higher Risk Patients
Keywords
pancreas divisum, pancreatic divisum, duct of Santorini, minor papilla stenosis, duct of Wirsung
