Endoscopic Ultrasound (EUS)

Endoscopic Ultrasound (EUS) a minimally invasive procedure that assess gastrointestinal and lung diseases.

A special endoscope uses high-frequency sound waves to produce detailed images of the lining and walls of the digestive tract and chest, nearby organs such as the pancreas and liver, and lymph nodes. When combined with a procedure called fine-needle aspiration, EUS allows the doctor to sample (biopsy) fluid and tissue from the abdomen or chest for analysis. EUS with fine-needle aspiration can be a minimally invasive alternative to exploratory surgery.

Why is it done?

EUS is used to find the cause of symptoms such as abdominal or chest pain, to determine the extent of diseases in the digestive tract and lungs, and to evaluate findings from imaging tests such as a CT scan or MRI.

EUS may help in the evaluation of:

• Cancer of the colon, esophagus, lung, pancreas or stomach, and ampullary and rectal cancers
• Lymphoma
• Barrett’s esophagus
• Neuroendocrine tumours
• Pancreatitis and pancreatic cysts
• Bile duct stones
• Sarcoidosis

EUS can help:

• Assess how deeply a tumour penetrates the abdominal wall in esophageal, gastric, rectal, pancreatic and lung cancers
• Determine the extent/stage of cancer, if present
• Determine if cancer has spread to the lymph nodes or other organs
• Provide precise information about non-small cell lung cancer cells, to guide treatment
• Evaluate abnormal findings from imaging tests, such as cysts of the pancreas
• Guide drainage of pseudocysts and other abnormal collections of fluid in the abdomen
• Permit precise targeting for delivering medication directly into the pancreas, liver and other organs

EUS is performed on an outpatient basis and is well-tolerated by most people.

What are the risks involved?

EUS is generally safe when performed at a centre with an experienced and expert health care team. The doctor discusses with the patient the risk of complications from EUS. These risks are most commonly associated with fine-needle aspiration.

Risks may include:

• Bleeding
• Infection
• Tearing of the intestinal wall or throat
• Pancreatitis, if fine-needle aspiration of the pancreas is done

These risks associated with Endoscopic ultrasound can be prevented by following the instructions of the doctor carefully during the preparation process of Endoscopic ultrasound.

There might be some signs and symptoms observed after the Endoscopic ultrasound scan, which are to be taken care of. However, consulting the doctor is always advisable:

• Difficulty in breathing
• Fever
• Pain in the chest
• Difficulty in swallowing
• Vomiting
• Dark or black coloured stool
• Persistent or severe pain in the abdomen

How to prepare for the procedure

The doctor will give specific instructions to prepare for the EUS. The patient may be asked to:

• Fast before EUS to make sure stomach is empty. Generally, fast for at least 6 hours before the test is needed.
• Prepare the rectum, if EUS is being done in the rectal area. Patient may be asked to take a laxative or have an enema and to follow a liquid diet before the procedure.
• Stop taking certain medications, such as blood thinners. Blood thinners may increase the risk of bleeding if fine-needle aspiration is performed during EUS. If one has chronic conditions, such as diabetes or high blood pressure, then the doctor would give specific instructions regarding medications.
• Plan ahead for your recovery, if the patient would be sedated before EUS. Most people who have EUS are given medication to relax them.

What are the expected results?

The gastroenterologist and pulmonologist are the ones who interpret the images of the scan carefully. If the scan is combined with the fine needle aspiration, then the lab report is sent by the pathologist and the doctor discusses the finding with the patient and plans for the treatment if any abnormality is detected.