Cystogastrostomy (EUS-Guided Cyst Drainage)

In some patients who have had severe pancreatitis, a collection of fluid forms around the pancreas. If a wall grows around that collection over the following weeks, it is called a pseudocyst.

Cystogastrostomy is the opening of a route with an endoscope between that cyst and the stomach, so that its contents drain straight into the stomach. No operation is needed, and no drain is brought out through the abdominal wall.

When is it needed?

Most small pseudocysts that cause no complaints disappear of their own accord and need nothing done. Drainage is considered when:

• The cyst presses on the stomach or duodenum and prevents eating
• There is abdominal pain that will not settle
• The cyst becomes infected
• The cyst goes on growing
• It presses on the bile ducts and causes jaundice

The cyst has to lie close enough to the wall of the stomach or bowel for the procedure to be possible.

Consent form

The clinic’s consent form will be signed.

How is it done?

The procedure is done with an endoscope carrying an ultrasound probe at its tip (EUS). Under ultrasound guidance:

1. The best point of entry between the stomach wall and the cyst is chosen; the vessels in between are seen and avoided.
2. A needle is passed from that point into the cyst.
3. A guidewire is fed through the needle into the cyst cavity.
4. The track made over the wire is widened with a special knife and a balloon.
5. A stent is placed to keep the track open.

There are two kinds of stent. Double pigtail plastic stents are placed two or three side by side; they are cheap and effective, but can block, and are generally taken out at a second endoscopy after six to eight weeks. Lumen-apposing metal stents (LAMS) are wide-bore, hold the two organs against each other, and allow an endoscope to be passed through them to clean out the cavity.

Afterwards

The patient is watched in hospital for a time. Whether the cyst is shrinking is followed with ultrasound or a scan. Once the cyst has gone, a check endoscopy is arranged to remove the stent.

What are the risks?

• Bleeding — the vessels are imaged during the procedure and avoided as far as possible
• Infection
• The stent moving out of place (migration)
• Perforation and leakage of fluid into the abdominal cavity — uncommon

This is an advanced procedure and should be done in an experienced centre.