To understand pancreas divisum, it is essential to first understand the normal anatomy and function of the pancreas and its ducts. The pancreas is a glandular organ located deep in the abdomen, behind the stomach. It has two main jobs: producing hormones like insulin and, for its digestive function, producing powerful enzymes. These digestive juices are collected into a system of ducts within the pancreas that drain into the small intestine.

• In a developing fetus, the pancreas actually starts as two separate pieces, a larger dorsal bud and a smaller ventral bud, each with its own drainage duct.
• In normal development, these two buds rotate and fuse together to form the final, single pancreas. Their duct systems also fuse. The main duct from the larger dorsal bud connects to the duct from the smaller ventral bud, forming one large, high-capacity main pancreatic duct (the Duct of Wirsung). This main duct then joins with the common bile duct and drains through a large opening in the small intestine called the major papilla.
• In this normal anatomy, a smaller, secondary duct (the Duct of Santorini) from the dorsal portion may still drain a small amount of juice through a tiny, separate opening called the minor papilla.

Pancreas divisum, which literally means “divided pancreas,” is what happens when this fusion of the duct systems fails to occur during fetal development. The two duct systems remain separate, just as they were in the early embryo.

A helpful analogy is to think of the pancreas as two separate neighborhoods being built next to each other, each with its own network of small sewer lines.

• In normal development, late in construction, the crews are supposed to connect the two neighborhoods’ sewer systems into one large, high-capacity main pipeline that exits through a large drainage port (the major papilla).
• In pancreas divisum, this final connection never happens. The two neighborhoods remain “divided.”
• As a result, the smaller neighborhood (the ventral pancreas) drains through the large, high-capacity major papilla. But the much larger neighborhood (the dorsal pancreas), which produces the majority of the pancreatic fluid, is now forced to drain all of its output through its own original, much smaller and less-developed drainage port (the minor papilla).

The potential problem in pancreas divisum is one of relative obstruction. There is a long-standing theory that for some individuals, the tiny opening of the minor papilla is not large enough to handle the volume of fluid being produced by the bulk of the pancreas. This can lead to a “traffic jam” and a backup of pressure within the pancreas, which may trigger inflammation, or pancreatitis.

In my experience, most patients are unaware they even have pancreas divisum until they’re investigated for recurrent abdominal pain or pancreatitis.

Pancreas divisum is caused by the failure of the dorsal and ventral pancreatic ducts to fuse during the 6th to 8th week of fetal life. This is a random error in embryological development. The specific reason why this fusion fails to occur in some developing babies is unknown. It is not caused by any action or inaction of the mother during pregnancy. It is simply a variation in how the organ is formed.

Patients often ask if they caused it somehow, i reassure them it’s something they were born with, and not related to diet, alcohol, or medications.

Pancreas divisum is a congenital anomaly, meaning you are born with it. It is not contagious and is not considered a disease you “get.” It is a structural variation.

• In the vast majority of cases, it is a sporadic finding, meaning it occurs by chance and is not directly inherited.
• While it is a “birth defect,” it is not considered a genetic disease in the typical sense and does not run in families with a predictable pattern.

In my experience, I explain to patients that pancreas divisum is a congenital condition, meaning they’ve had it since birth, though it may only be discovered later in life.

The single most important fact about pancreas divisum is that over 95% of individuals who have this anatomical variation are completely asymptomatic. They live their entire lives without any health problems related to it and are often unaware they even have it. Most diagnoses are made as an incidental finding on an MRI or CT scan being performed for an unrelated reason.

In the small minority of people where pancreas divisum is thought to cause problems, the symptoms are not from the divisum itself, but from the pancreatitis (inflammation of the pancreas) it may trigger. The link between pancreas divisum and pancreatitis remains somewhat controversial, and it is typically only considered as a potential cause after all more common causes of pancreatitis (like gallstones and alcohol use) have been definitively ruled out.

When symptoms are present, they are those of recurrent acute or chronic pancreatitis:

• Abdominal Pain: This is the primary symptom. It is often a severe, deep, boring pain in the upper abdomen that can radiate through to the back.
• Nausea and Vomiting, especially after eating.
• In cases that progress to chronic pancreatitis, symptoms of malabsorption may develop, such as oily stools (steatorrhea) and weight loss.

Clinically, I’ve seen that most people with pancreas divisum never have symptoms, but a small subset experience repeated inflammation due to impaired pancreatic drainage.

As most people with pancreas divisum are asymptomatic, it is often found by accident. For those with recurrent unexplained pancreatitis, a doctor (usually a gastroenterologist) will perform specific imaging tests to visualize the pancreatic ducts.

• Magnetic Resonance Cholangiopancreatography (MRCP): This is the best non-invasive test for diagnosing pancreas divisum. An MRCP is a specialized type of MRI that uses sophisticated software to create a detailed, 3D map of the bile and pancreatic ducts. This imaging can clearly show that the main pancreatic duct (from the dorsal pancreas) is not connected to the common bile duct and is instead draining separately through the minor papilla.
• Endoscopic Retrograde Cholangiopancreatography (ERCP): This is the most definitive diagnostic test, but it is invasive and carries risks, so it is often used when therapy is also being considered. In this procedure, a flexible endoscope is passed through the mouth down to the small intestine. A small catheter is inserted into the papillae, and contrast dye is injected.
  • In pancreas divisum, when dye is injected into the major papilla, the X-ray will show only the small, thin duct of the ventral pancreas.
  • The endoscopist can then cannulate the minor papilla and inject dye, which will reveal the large, dominant dorsal duct draining the rest of the pancreas, confirming the diagnosis.
• Other Imaging: A CT scan or an endoscopic ultrasound (EUS) can also sometimes suggest the diagnosis of pancreas divisum.

In my experience, ERCP can both diagnose and treat pancreas divisum, though I typically reserve it for patients with recurrent pancreatitis or unclear imaging results.

For the vast majority of people who are found to have asymptomatic pancreas divisum, absolutely no treatment or follow-up is necessary. It is a benign anatomical variant and should not be a source of worry.

Treatment is only ever considered for a small, select group of patients who suffer from recurrent episodes of acute pancreatitis or chronic pancreatitis pain, and in whom pancreas divisum is the only identifiable potential cause after an exhaustive workup has ruled out all other possibilities.

The goal of treatment in these specific cases is to relieve the relative blockage at the minor papilla to improve the drainage of pancreatic juice from the main (dorsal) part of the pancreas.

1. Endoscopic Therapy

This is the first-line treatment approach and is performed during an ERCP.

• Minor Papilla Sphincterotomy: The gastroenterologist passes a small wire with an electrical current (a sphincterotome) through the endoscope and makes a tiny cut to enlarge the opening of the minor papilla. This widens the drainage port to relieve the pressure backup.
• Stenting: Following the sphincterotomy, a small plastic tube called a stent is often temporarily placed into the newly enlarged opening to keep it from scarring shut as it heals. This stent is typically removed during a repeat endoscopy a few weeks later.

2. Surgical Treatment

Surgery is considered a last resort and is reserved for patients with debilitating pancreatitis who have not found relief with endoscopic therapy. A surgeon can perform a surgical sphincteroplasty, which more permanently widens the opening of the minor papilla.

I’ve seen good symptom relief in select patients through endoscopic minor papilla sphincterotomy, it helps improve pancreatic drainage and reduce flare-ups.

Pancreas divisum is the most common congenital variation of the pancreas, present in up to one out of every ten people. For the overwhelming majority, it is a harmless anatomical quirk discovered by accident, causing no symptoms and requiring no treatment or concern. Its importance lies in the small minority of individuals with recurrent, unexplained pancreatitis, where it may be a contributing factor. In these select cases, advanced endoscopic therapies can help relieve the anatomical bottleneck and reduce painful attacks. In my experience, many patients feel reassured once they understand that pancreas divisum isn’t dangerous by itself, it only needs treatment if symptoms develop.

The National Pancreas Foundation. (n.d.). Pancreas Divisum. Retrieved from https://pancreasfoundation.org/patient-information/pancreatic-disease/pancreas-divisum/

American Society for Gastrointestinal Endoscopy (ASGE). (n.d.). ERCP (Endoscopic Retrograde Cholangiopancreatography). Retrieved from https://www.asge.org/home/patients/patient-information/understanding-ercp

Cleveland Clinic. (2022). Pancreas Divisum. Retrieved from https://my.clevelandclinic.org/health/diseases/22473-pancreas-divisum