(and Pancreatic ductal disruption)
A collection of pancreatic juice enclosed by an fibrous
- pseudo because it is not lined by epithelium.
- cause symptoms if: 1) compress adjacent structures; ii) get
infected; iii) rupture
Up to 16-50% of acute pancreatitis
Or pancreatic trauma
--> arise from disruption of major or minor pancreatic ducts
following inflammation or injury.
- chronic fibrosis, duct irregularity, duct obstruction and dilation
--> duct disruption, producing the pseudocyst
- diagnostic problem as difficult to know if problem is the
pseudocyst or necrosis / ductal obstruction.
(As per Revised Atlanta Criteria)
Majority of pancreatic collections resolve
- some fail to; enzymes incite a local inflammatory response
--> walled off with fibroblasts accumulating and laying down a
May be intra-pancreatic, but usually extra, occupying the lesser
- may also involve small bowel mesentery, transverse mesocolon, or
behind right and left colons.
Traditionally stated that it takes 4-6 weeks at least to appear from
onset of pancreatitis
- with modern imaging, if can identify a clear wall earlier, then it
is a pseudocyst not an acute fluid collection.
Leakage or rupture --> pancreatic ascites
- can be branch, main duct, or if severe disease, a whole necrotic
pancreatic tail disruption.
- may cause a pancreaticopleural fistula
- if infected = pancreatic abscess
Most communicated with the duct and contain watery fluid rich in
- most have persistent elevations of enzymes in serum.
May occur singly, or as small multiple cysts.
If >6cm, symptoms more likely (tender, mass effect)
- gastric outlet obstruction may occur, or compress stomach with
- obstructive jaundice may similarly occur.
- can rupture
'Pancreatic Ductal Disruption'
Another state where pancreatic ascites or pleural effusions follow
enzyme-rich fluid spilling beyond pancreas.
In general, where there is a duct disruption, the duct should be
- pancreatic fluid collections; may be trivial leak from ductules or
persisting leak from a major duct.
- pseudocysts (most common complication of duct disruption)
- organized pancreatic necrosis (after nec. panc.).
- pancreatic fistula, often a complication of pancreatic resections
or damage; can be persistent drainage
- pancreatic ascites; generally causes peritonitis; initial
collection is in the lesser sac.
- pancreatic pleural effusions; enzyme rich fluid may traverse
foramina to cause thoracic sequelae
Duct anatomy is important for management, whether there is
stricturing, obstruction, disruption or leak.
- will help guide conservative vs transpapillary stenting etc.
Location: more common in head (50%) vs body (30%) and tail (20%) but
this doesn't change management much.
Most will show acute +/- persisting fluid collections in context
of their underlying disease
But some will present with recurrent pancreatitis and recurrent
Management of ductal disruptions
Supportive measures as per cause, and intervene for
complications or symptoms.
Endoscopic, surgical and percutaneous approaches used, as discussed
further below re pseudocysts.
Nausea and vomiting
Possibly weight loss from obstruction
Even lower extremity oedema from IVC obstruction.
portal, SM or splenic vein thrombosis
Severe abdominal pain (from pancreatic ascites)
from erosion into GI tract mucosa or vessels
Cheap and effective
Can show the cystic mass but poor for anatomy of relationships.
Primary means of imaging
Rounded, fluid-filled mass, defined wall of uniform thickness.
Evaluate pancreas for pathology; necrosis, atrophy,
Though difficult to see duct status from CT
Helpful to differentiate pseudocyst and cystic neoplasm.
Excellent soft-tissue contrast capability; may show cyst wall
irregularities and septations suggestive of neoplasms.
- internal dependent debris is highly specific for pseudocyst.
If concern for neoplastic cyst, then need aspiration and analysis,
e.g. via EUS-FNA.
- analyze fluid for tumor and genetic markers, mucin, enzymes and
cells, gram stain and culture
MRCP / ERCP
Can show connections between main ducts and pseudocysts.
Don't want to introduce infection though; MRCP reduces this risk vs
Many can be managed conservatively.
- 40% resolve within 6 weeks
- those that don't continue to resolve over up to a year, and
complication rate is low <10cm.
- even large cysts can be safely observed, despite lower
invasiveness of modern interventions.
- less likely to resolve if >5cm
Perform serial imaging (e.g. 6 weekly or 3 monthly); those that are
enlarging may require intervention
MRCP / ERCP
Prior to intervention to define anatomy and
exclude strictures preventing resolution
If symptomatic, enlarging, or causing complications, may need
Various options, eg cystjejunostomy, distal pancreatectomy...
But pseudocyst drainage is now the usual pathway
- percutaneous catheter drainage in poor candidates, but introduces
infection and morbidity, plus external fistula formation is slow to
- no evidence for benefit of octreotide.
Internal drainage now preferable:
- 85% success
- endoscopically via transpapillary drainage (esp for head cysts,
but can lead to infection), cyst-gastrostomy or cyst-duodenostomy
--> USS, avoid vessels, aspirate to confirm diagnosis, then drain
by incising through wall of stomach / duodenum, place a stent
- in some instances, endoscopic dilation with a balloon catheter can
help to widen the opening and to facilitate drainage.
Transpapillary drainage aims to stent across the duct, excluding the
communication to the cyst, permitting healing without drainage.
Surgically treated via cyst-gastrostomy, cyst-duodenostomy or
1. Pseudocyst after pancreatitis
- persistent communication with ductal system should be suspected.
Transpapillary approach for those in proximity with main duct
Else cyst-gastrostomy (endoscopic)
For ones that are difficult to drain due to anatomical location
- perform MRCP to determine ductal communication.
- if isolated --> drain percutaneously
- if communication --> Roux-en-Y cystojejunostomy
If septic, drain externally.
2. Pseudocysts with pancreatic necrosis.
- usually associated with significant ductal disruption and thick
Image to determine quantity and nature of debris (MRI)
Intervention tailored to indications
- drain infection
internal drainage if possible.
3. Chronic pancreatitis
- structured ducts, difficult to separate symptoms
Transpapillary approaches in a specialist unit.
Method: Open Cyst-gastrostomy
longitudinal anterior gastrostomy
Needle aspiration to locate pseudocyst if not obvious.
Open gastric wall and cyst cavity
Send a section of the wall for histological analysis.
Running locking suture (2-0 PDS joining cyst wall to stomach wall.
When not directly adherent to stomach, can do Roux drainage.
If concerned re malignancy, surgical resection.