So in the last lecture, I mentioned that the guideline state that we shouldn't intervene on asymptomatic pseudocysts.

The major problem with pseudocysts is they are so hard to predict.

Spontaneous resolution occurs in about a third of patients with the pseudocyst,

and you will also find some asymptomatic

pseudocist, just incidentally on imaging.

And then there are the others that cause abdominal and back pain.

Some will obstruct the biliary system or even the duodenum.

They can be inflammatory and erode into the bowel or surrounding vessels and cause a life-threatening

hemorrhage. Therefore, the uncertainty of what clinically will happen with this pseudocyst

understandably makes physicians uncomfortable. You can't totally reassure the patient that everything will be fine, but being

prophylactically aggressive can increase harm. So what exactly is a pancreatic pseudocyst? It's a collection

of pancreatic secretions contained within a fibrous sac that is formed by inflammatory cells

and fibroblasts, meaning a fibrous capsule forms.

This fibrous lining does not have an epithelial layer, and the pseudocyst form late,

meaning four weeks or more after pancreatitis occurs.

You certainly will see cases of fluid collections less than four weeks after acute pancreatitis,

but those are called acute peripancreatic fluid collections. It is important to understand there is also an entity

called walled-off pancreatic necrosis that occurs more than four weeks out after an occurrence

of necrotizing pancreatitis. It is not an arbitrary distinction from a pseudocyst because the need and types of intervention

are different with Waldorf pancreatic necrosis.

In Waldorf pancreatic necrosis, you may need surgical necrosectomy or image-guided percutaneous

drains among the other possible interventions.

...