Pancreatic Pseudocyst Management

Anatomic Definition and Diagnostic Approach

A pancreatic pseudocyst is a collection of pancreatic juice enclosed by a wall of fibrous or granulation tissue that arises following an attack of acute pancreatitis, requiring four or more weeks from onset to form 1, 2, 3
The pseudocyst wall consists of fibrous or granulation tissue, distinguishing it from acute fluid collections which lack this organized wall structure 1
Acute fluid collections occur early in pancreatitis and always lack a wall of granulation or fibrous tissue 1
Pancreatic abscess contains pus with little or no pancreatic necrosis 1
Infected necrosis involves non-viable pancreatic parenchyma with infection, tripling mortality risk 1
All localized collections following necrotizing pancreatitis should be considered localized necrosis until proven otherwise with definite imaging evidence of fluid rather than necrotic tissue 4
CT scanning is the most common diagnostic tool, though cannot reliably distinguish pseudocyst from other peripancreatic collections alone 4
Ultrasound or MRI should be obtained to confirm fluid (as opposed to necrotic tissue) before diagnosing pseudocyst 4

More than half of acute fluid collections resolve spontaneously, and in otherwise stable patients they do not require treatment 5
Repeat CT scanning every two weeks in severe cases to monitor for complications 5
Patients with extensive necrotizing pancreatitis or complications should be managed in or referred to specialist units with multidisciplinary expertise, full intensive care facilities, emergency ERCP capability, and expert radiological support for percutaneous procedures 1

Hemorrhage: CT attenuation values >50 HU suggest blood content 6
Infection: Indicated by sudden high fever, though unremitting low-grade fever is common in necrotizing pancreatitis without necessarily indicating infection 5
Rupture: Free gas in retroperitoneum on plain films is a late sign of infection with gas-forming organisms 5
Biliary or gastric outlet obstruction: Epigastric mass with vomiting suggests persistent fluid collection 5

A pancreatic pseudocyst is a collection of pancreatic juice surrounded by a fibrous or granulation tissue wall that develops at least 4 weeks after the onset of acute pancreatitis; collections appearing earlier are classified as acute fluid collections because they lack an organized wall. 7
The pseudocyst wall is composed of fibrous or granulation tissue without an epithelial lining, distinguishing it from true cysts. 7

Magnetic Resonance Imaging (MRI) or Magnetic Resonance Cholangiopancreatography (MRCP) is the preferred modality for pregnant patients and can demonstrate a communication between the cyst and the main pancreatic duct. 8
Dynamic contrast‑enhanced CT performed 3–10 days after admission helps delineate the extent of pancreatic and peripancreatic necrosis in severe cases. 7

Patients with extensive necrotizing pancreatitis or complications that may need intensive care, interventional radiology, endoscopy, or surgery should be managed in or referred to a specialist unit. 7
Essential capabilities of such a specialist unit include:
Transfer to a specialist unit is indicated for patients with extensive necrotizing pancreatitis. 7

The most common complication after non‑operative management is the development of a new pseudocyst. 8
Infection occurs in 7–25 % of pancreatic injuries, leading to abscess formation or intra‑abdominal sepsis. 8
Pancreatic fistula develops in 10–35 % of major pancreatic injuries following operative drainage or resection. 8
Post‑traumatic pancreatitis has an incidence of approximately 17 % after pancreatic injury. 8