Endoscopic Ultrasound and Fine Needle AspirationAshish Chopra, MD, Gastroenterology

www.SpringfieldClinic.comwww.SpringfieldClinic.com

Case Presentation #1

• 34 y/o female with no significant past medical history was admitted with abdominal pain and a CAT scan was performed and found to have appendicitis.

• In addition to the appendicitis, something else was found in her pancreas.

 • She underwent an appendectomy and after her

hospitalization was complete, she was referred to me as an outpatient for further evaluation.

What could this be?

• Cyst• Tumor

– Benign– Malignant

• Cluster of blood vessels• Normal variant

• We need a biopsy !!!!

Case Presentation #2

• 69 y/o male with multiple medical problems on multiple medications, including blood thinners that should not be stopped, found to have elevated liver tests and abdominal pain consistent with his “gallbladder prior to it being removed.”

• The question is whether or not he has a gallstone stuck in his bile duct.

• Patient has a pacemaker so MRI is not possible.

Case Presentation #2

• A test that could be performed is an ERCP, though this requires stopping of his blood thinner and has a 5% chance of developing pancreatitis ( inflammation of the pancreas).

• Is there a test that could be done to tell if he has a stone in the bile duct without placing him at risk for pancreatitis and that would still allow him to stay on his medications?

What is EUS?

• EUS (endoscopic ultrasound) is a procedure that uses an endoscope (a thin flexible tube with a light and camera) with a built-in special ultrasound probe.

• A typical endoscope is used to examine the lining of the esophagus, stomach, duodenum, and colon. However, this scope cannot visualize things outside of the GI tract.

What is EUS?

• With EUS, the scope can further visualize and characterize abnormalities of:

• the lining of the gastrointestinal tract (esophagus, stomach, duodenum, colon, and rectum),

• the pancreas• the gallbladder• the bile duct• lymph nodes

GI Tract

Biliary System

Radial EUS scope

Image sourced from: www.pentaxmedical.com

How does EUS work?

• Ultrasound waves are sent from the built-in ultrasound in the scope, which bounce off of the abnormality and back to the ultrasound transducer.

• The transducer then transfers the sound information into a processor unit.

• The processor then forms real time ultrasound images for interpretation by your physician.

Image sourced from: http://www.hpb.org.uk/

Why is EUS performed?

• EUS is used to help clarify an unexpected finding that was found on previous imaging (patient case 1).

• Using EUS, the abnormality in question can be studied and information regarding its size, depth, relationship to surrounding structures, and its origin can be ascertained.

• Other indications for EUS include tissue sampling, non-invasive ways to image the bile duct or pancreatic duct ( patient case 2) and staging of gastrointestinal cancers.

Image sourced from: http://www.medcyclopaedia.com

Image sourced from: http://www.medcyclopaedia.com

Image sourced from: http://www.hopkins_gi.org

How is EUS performed

• The patient is sedated with intravenous medications and in the case of an upper EUS, a bite block is placed in the patient’s mouth, which helps protect the mouth from the scope and helps guide the scope into the esophagus.

• After the patient is made comfortable, the EUS scope is carefully placed into the esophagus and the scope is advanced to the area in question.

How is EUS performed

• For example, if the abnormality is in the duodenum, the scope is advanced into and out of the esophagus and stomach, to the duodenum and the area in question is identified.

• For imaging of the head of the pancreas, the scope is placed in the duodenum and for the body and tail of the pancreas, it is kept in the stomach.

Fine Needle Aspiration

• This is a technique that is used to obtain a biopsy sample of a target lesion (mass, lymph node, cyst, etc.)

• Once the lesion has been adequately studied, color Doppler is used to make sure there are no blood vessels between the scope, the anticipated path of the FNA needle, and the lesion.

Fine Needle Aspiration

• Once this is verified, the needle is passed under real time ultrasound, and the needle is seen going into the lesion.

• The sample is then collected and given to the cytologist, who is in the room to provide immediate analysis.

• This can be done multiple times if needed, to obtain an adequate specimen and to increase the diagnostic yield.

Image sourced from: http://www.hopkins_gi.org

Image sourced from: http://www.olympusaustrailia.com

What are the benefits of EUS +/- FNA?

• Safe procedure• Can give immediate biopsy results• Can get to lesions that may be difficult to reach by

other modalities (i.e. surgical biopsy or CAT scan guided biopsy)

• Outpatient procedure

What are possible complications of EUS?

• As with all procedures, complications can occur, however, generally these are rare.

• Such complications include bleeding, infection, perforation (causing a hole in the esophagus, stomach, duodenum, or colon), medication reaction to the anesthetics, and death (though extremely unlikely).

• If FNA is performed of the pancreas, there is a 1% chance of developing pancreatitis.

How to prepare for an EUS

• Typically your physician will ask you not to have anything to eat or drink starting at midnight the day of your procedure.

• If you are having a rectal EUS, then your physician will likely have you take enemas prior to your examination.

• Let your doctor know what medications you are on as some of these may have to be adjusted prior to the procedure.

Back to case 1

• This patient needed to have a biopsy of the lesion in her pancreas so as to direct the management.

• The alternatives include surgical biopsy, needle biopsy under CAT scan guidance, or EUS with FNA.

• We chose EUS with FNA.

EUS findings in patient 1

EUS findings in patient 1

Patient 1

• This was found to be a solid pseudopapillary tumor of the pancreas and she is scheduled for removal of the tail of her pancreas and spleen.

Back to patient 2

• Recall this was a 69 y/o male whom we wanted to know if he had a bile duct stone without having to have him off of his blood thinners and without subjecting him to the risk of more invasive procedures, such as ERCP.

Biliary System

EUS of patient 2

Summary

• EUS is a safe procedure that allows the physician to see both inside and outside of the GI tract to help characterize lesions found on other forms of imaging.

• Many times, coupled with FNA, samples can be obtained in a safer more convenient way to help guide the patient to the appropriate treatment.