Endoscopic ultrasound (EUS) is an endoscopic technique used to visualise the layers of the gastrointestinal tract and surrounding internal organs. Areas that can be seen and examined include the oesophagus, stomach, duodenum, liver, gallbladder, pancreas and lungs. EUS uses a special endoscope (long flexible tube with a light and camera on the end) that has an ultrasound probe at the tip. It is with the ultrasound that the specialist can look at the individual layers of the wall of the gastrointestinal tract as well as outside the wall without having to perform an operation.
Why is EUS performed?
EUS provides more information than other imaging tests by providing detailed images of the digestive tract. EUS is often most commonly used to diagnose diseases of the pancreas, bile duct and gallbladder. In addition, EUS is also utilised to stage/determine the extent of spread of cancers of the respiratory and digestive systems e.g. depth of tumour, lymph node spread, major blood vessel involvement.
EUS often follows other investigations such as CT scan, MRI scan or gastroscopy where a lesion or other abnormality has been detected which requires further evaluation for diagnosis to determine treatment. EUS allows the specialist to obtain biopsies from deep lesions which would otherwise require more invasive/painful methods such as percutaneous (through the skin) or surgical approaches.
EUS can also be used for therapeutic applications such as bile duct and gallbladder access/drainage in the case of jaundice arising from cancer obstruction, and also for drainage of collections from complications of pancreatic inflammation.
Where is EUS performed?
EUS is typically performed in a tertiary hospital due to the expensive nature of the required equipment and highly technical nature of the procedure. Your procedure will be performed in University Hospital Geelong on one of Dr Ting’s lists. The procedure is similar to a gastroscopy except that it takes longer (30-60-minutes). Most cases are performed under deep sedation, but general anaesthesia may occasionally be required at the discretion of the attending anaesthesiologist. Diagnostic EUS is typically performed as a day procedure. Therapeutic or interventional EUS will usually require admission to hospital afterwards for observation or further management.
What preparation is required?
You will need to fast for at least 6 hours prior to the procedure. Generally, you should take all your regular medications with a sip of water even on the morning of the procedure. If you are any taking blood thinning medications (such as Aspirin, Persantin, Warfarin, Plavix, Xarelto) or NSAIDs, you must discuss whether these should still be taken in the days before the procedure. If you have a metal heart valve or pacemaker or are a diabetic, please inform your doctor.
What are the risks of EUS?
Like most other endoscopic procedures, EUS is safe and very well tolerated. However, no procedure is without risk, but complications with EUS are quite rare.
EUS without fine needle aspiration (biopsy) has a complication rate of 0.05% which is similar to other endoscopy procedures. The major complication of perforation is less than 0.01% where a tear of the gastrointestinal wall occurs, which can usually be repaired endoscopically but may even require surgery to close.
EUS with fine needle aspiration (biopsy) carries a slightly higher risk of complications but is still uncommon at around 0.5%. The passage of the needle through the gastrointestinal wall may cause minor bleeding. If there is significant bleeding, hospitalisation for observation and rarely transfusion may be required. Infections can occur following aspiration of fluid from cysts, and antibiotics may be given to prevent this. If the pancreas is biopsied, there is a small risk of pancreatitis (pancreatic inflammation) – this would require hospitalisation to administer pain relief, intravenous fluids, bowel rest and observation.
If you have a latex allergy, please advise your doctor, there is a component of the EUS equipment that utilises latex that will need to be removed prior to you having the EUS performed.
Morning procedure (Level 4 Operating Theatre, University Hospital Geelong)
These are done on Monday mornings from 8:00am till 12:30pm. You will need to be fasting from midnight prior to your procedure. You may take essential medications early in the morning (6am) with a small sip of water ONLY. Please present to the admissions desk at the main reception of the hospital at the predetermined time.
Afternoon procedure (Gretta Volum Centre, University Hospital Geelong)
These are done on Thursday afternoons from 1:30pm till 5:30pm. You will need to be fasting after only a light breakfast (slice of toast and cup of black tea/coffee ONLY). Fast from 8:00am and do not have anything to eat or drink (including lollies or even chewing gum). Present to the Gretta Volum Centre reception at the predetermined time.