How is EUS guided transmural pseudocyst drainage performed?
- Transmural EUS guided pseudocyst drainage can be performed by a multistep or single-step procedure.
- The multistep procedure involves EUS localization of the pseudocyst, followed by transmural drainage using a side-viewing endoscope (duodenoscope).
- Presence of gastric or duodenal varices and lack of bulging of the stomach or duodenum produced by the pseudocyst are contraindications to using a duodenoscope for transmural drainage.
- The single-step procedure allows the endoscopist to achieve drainage of the pseudocyst with a single linear array EUS scope.
- This technique allows continued EUS imaging during the whole procedure. Presence of varices or the lack of a bulge does not preclude the performance of transmural drainage with this technique.
- The placement of large-bore endoprostheses (10 Fr double pigtail stents) requires the use of a therapeutic EUS scope.
- After the needle pathway is found to be safe (flow or Doppler interrogation), a 19-gauge FNA needle is advanced into the pseudocyst and cyst fluid is aspirated. A 0.035-inch guidewire is subsequently introduced through the needle into the pseudocyst cavity.
- Fluoroscopy can be used for guidance. After the guidewire is coiled into the cyst, the FNA needle is removed, leaving the guidewire in place. Opening of the gut-cyst wall is performed by cutting with the needle knife, which is subsequently removed, leaving the guidewire in place.
- Dilatation of the gut-cyst opening is performed using a 10-mm biliary balloon dilator over the guidewire.
- Dilation is followed by the placement of the first 10 Fr 2- to 3-cm double pigtail stent into the cyst.
- The original guidewire is removed from the cyst. Placement of the second 10 Fr 2- to 3-cm double pigtail stent is performed over the wire after recannulation of the opening next to the first stent with the sphincterotome.
