Treatment of Annular Pancreas
Surgical bypass procedures are the treatment of choice for symptomatic annular pancreas, with duodenojejunostomy, gastrojejunostomy, or duodenoduodenostomy being the preferred surgical options rather than resection of the annular tissue. This approach effectively relieves obstruction while avoiding the high risk of complications associated with direct pancreatic tissue resection 1, 2.
Clinical Presentation and Diagnosis
Annular pancreas is a rare congenital anomaly characterized by pancreatic tissue encircling the duodenum. The clinical presentation varies based on age and type:
- Adults: Often asymptomatic until middle age or later, with a mean age at diagnosis of 55 years 3
- Common presentations:
- Abdominal pain (50%)
- Duodenal obstruction/gastric outlet obstruction (31%)
- Acute pancreatitis (16%)
- Incidental finding (60% of cases) 3
Diagnostic Approach
- ERCP: Diagnostic modality of choice 1
- CT scan: Most commonly used initial imaging (64% of cases) 3
- MRI/MRCP: Helpful for visualizing pancreatic anatomy
- Upper GI series: May show characteristic "double bubble" sign
Treatment Algorithm
1. Asymptomatic Patients
- No intervention required 3
- Regular follow-up to monitor for development of symptoms
2. Symptomatic Patients
A. Duodenal Obstruction
- First-line treatment: Surgical bypass procedure 2
- Duodenojejunostomy (preferred)
- Gastrojejunostomy
- Duodenoduodenostomy
- Approach: Laparoscopic approach is feasible and safe when performed by experienced surgeons 4
B. Acute Pancreatitis
- First-line treatment: Conservative management 3
- IV fluids
- Pain control
- Nutritional support
- Second-line: Surgical intervention only if conservative management fails or complications develop
C. Associated Conditions
- Peptic ulcer disease: Appropriate medical management
- Biliary obstruction: Endoscopic sphincterotomy and biliary stent placement may be therapeutic 2
Classification and Surgical Considerations
Two distinct subtypes of annular pancreas influence treatment decisions 5:
- Type 1 (Extramural): Presents with high gastrointestinal obstruction
- Treatment: Bypass procedure
- Type 2 (Intramural): Presents with duodenal ulceration
- Treatment: May require subtotal gastrectomy with or without vagotomy
Important Considerations
- Avoid direct resection of the annular pancreatic tissue due to high risk of pancreatic fistula, pancreatitis, and bleeding
- Bypass procedures are safer and equally effective in relieving symptoms
- Laparoscopic approach offers advantages of minimally invasive surgery with shorter hospital stays (average 4 days) and faster recovery 4
- Individualized approach based on specific symptoms, anatomical considerations, and patient factors
Pitfalls to Avoid
- Attempting to resect the annular pancreatic tissue
- Delaying surgical intervention in patients with significant duodenal obstruction
- Overlooking associated conditions (e.g., pancreatitis, biliary obstruction)
- Unnecessary intervention in asymptomatic patients
In summary, bypass procedures represent the safest and most effective approach for symptomatic annular pancreas, with the specific technique determined by the patient's presentation and anatomical considerations.