Why EUS is done
- Looking at pancreatic cysts and masses, and sampling them
- Finding small bile duct stones, sometimes avoiding an unnecessary ERCP
- Searching for the cause of unexplained or repeated pancreatitis
- Assessing lumps under the lining of the stomach or food pipe
- Staging some cancers of the food pipe, stomach, pancreas and rectum
- Sampling enlarged lymph nodes, for example when TB or cancer is suspected
How it's done
It's similar to an upper endoscopy but takes a little longer, usually 20–45 minutes, under sedation. If a sample is needed, a thin needle is passed through the scope into the target under real-time ultrasound guidance (FNA or FNB). There's no cut on the skin.
Risks
Diagnostic EUS has a risk similar to upper endoscopy. When a needle sample is taken, the risk of bleeding, infection or pancreatitis is low, around 1–2% or less in published series. Cyst sampling may need preventive antibiotics.
Results
Images are discussed with you after you're awake. Sample results usually take a few days. Sometimes a sample isn't conclusive and needs repeating; we'll talk about this in advance.
Common questions
Is EUS painful?
With sedation, most people are comfortable. A mild sore throat afterwards is common.
EUS or MRI: which is better?
They answer different questions and often complement each other. EUS is closer and can take samples; MRI/MRCP is non-invasive and maps the whole area.