EUS (Endoscopic Ultrasonography)


Endoscopic Ultrasonography (EUS) is an advanced endoscopic technique that has recently played a critical role in gastroenterology practice. It provides the opportunity to obtain detailed images of the esophagus, stomach and intestines using a specialized ultrasound device attached to the tip of the endoscopy instrument.

EUS is particularly sensitive in identifying the layers from which tumors originate, thanks to the ability of ultrasound to take very close images from inside the organs. This information helps to understand the nature of the tumor and plays a vital role in treatment planning.

Another advantage is the ability to take biopsy samples from the stomach and intestines, as well as adjacent organs such as the pancreas and liver, and lymph nodes. For example, pancreatic tumor samples, which could previously be obtained through an operation or a puncture of the abdominal skin, can now be obtained endoscopically, by entering the stomach through the mouth and using a thin needle. These biopsy samples are removed through the endoscopic instrument through the mouth.

This technique is used not only in gastroenterology, but also in the evaluation and biopsy of thoracic lymph nodes in lung cancer patients, as well as in the staging and diagnosis of lung cancer.

Who is the EUS Procedure Suitable for?

The EUS (Endoscopic Ultrasonography) procedure is generally considered an appropriate option in the following cases

  • Determining the depth and stage of cancers of the esophagus, stomach and intestines
  • Evaluation and diagnosis of tumors and similar masses in these organs by taking biopsies
  • Evaluation of pancreatic masses and diagnosis by endoscopic biopsy
  • Biopsy of lymph nodes in the chest cavity and abdomen
  • Performing a liver biopsy
  • Drainage of pancreatic cysts
  • Nerve block to reduce pain in cancer patients

Application Method and Advantages

As with all endoscopic procedures, EUS is also performed under anesthesia. For this, intravenous medication is administered so that the patient falls asleep and thus does not feel any pain during the procedure. This is a superficial anesthesia, not as deep as in surgeries. However, anesthesia is given at a level where the patient does not feel any pain and does not remember the procedure, and the patient is woken up at the end of the procedure.

The procedure is no different from a normal endoscopic procedure. After intravenous medication is administered, the patient is put to sleep and while the patient is under anesthesia, a special endoscopy device with an ultrasound device at the end is inserted through the mouth or anus depending on the area to be examined. In oral procedures, the area to be examined from the esophagus, stomach or small intestine is determined and ultrasound examination is performed from this area. In this way, very clear images are obtained and a detailed examination is performed as the area to be examined is viewed from very close neighboring organs. The procedure can only be a diagnostic examination or evaluation, or if a suspicious mass is seen, a needle is sent through the endoscopy device to take a biopsy from the mass and the procedure is terminated.

One of the most important advantages of EUS is that it provides very detailed imaging of the organs in the digestive system and also allows biopsies to be taken from suspicious masses in these organs. While surgery was previously required to take a biopsy from a mass in the pancreas, biopsy can now be easily performed with the EUS method without the need for surgery. It is also the most sensitive method for determining how deep a cancer in the digestive system has spread. In addition, it is now used to evaluate not only the digestive system but also other systems. For example, it is one of the most practical methods for evaluating lymph nodes in the chest or abdominal cavity for cancer.

Can the Pancreas be Imaged with EUS?

Today, EUS is one of the most sensitive methods used for the diagnosis of pancreatic diseases. This method has a very important place both in visualizing and evaluating the pancreas very clearly and in diagnosing the masses in the pancreas. In pancreatic masses, biopsy procedures previously performed under CT (computed tomography) or by opening the abdomen have now been replaced by biopsy under EUS. After entering the stomach with a special endoscopy tool, the pancreas, which is located just behind the stomach, is evaluated very clearly with ultrasound examination through the stomach. If a suspicious mass is seen in the pancreas, it provides the opportunity to take a biopsy from the mass in the pancreas with the help of a thin needle sent through the stomach or to drain it if there is a cyst.

Internal organs or nearby structures can also be visualized with the EUS procedure, including

  • Lungs
  • Lymph nodes in the center of the chest
  • Liver
  • Gallbladder
  • Bile Ducts
  • Pancreas

Length of Hospitalization

There is usually no need to stay in hospital after the EUS procedure. After the procedure, the patient is waited for about 20 minutes for the anesthetic effect to wear off until the patient feels well and then discharged.

Since anesthesia will be administered during the procedure, at least 8 hours of fasting is required as in all endoscopic procedures. Otherwise, no special preparation is required. If the procedure is for the large intestine, bowel cleansing is required. In addition, if a biopsy is planned during the procedure and the patient is regularly taking blood thinners, the blood thinners should be stopped before the procedure.

What are the Risks of the Procedure?

EUS is a very safe procedure when performed by experienced hands. One of the possible risks of the procedure is bleeding during biopsy. However, this risk is quite low if the necessary precautions are taken in experienced hands and the vascular structures are carefully examined before biopsy.