Tools and techniques, EUS-guided liver biopsy. Disclaimer. EUS-guided liver biopsy, needle types, and suction methods. We have nothing to disclose. Overview. EUS-guided biopsy of a patibility mass was initially described in 1997. EUS-guided liver biopsy for routine use was later reported in 2008. It can be used in lieu of CT or ultrasound-guided percutaneous biopsy or transjugular biopsy. In this video, we describe the needle types and suction modalities that can be used in this technique. Indications. Diagnosing etiology of complex liver disease. Staging of liver disease. Tissue acquisition of focal hepatic lesions. And this is not FDA approved. Contraindications. Patients who cannot tolerate sedation. Patients with gastric outlet obstruction. Those with no clear path for biopsy. Patients with abnormal coagulation. And patients who are hemodynamically unstable. Needle types. Here we have a list of needle types that have been used for EUS-guided liver biopsy. As you can see, the QuickCore needle is no longer on the market. The FNA needles include EchoTip and Expect, as well as Expect Flex. The EchoTip and Expect needles come in 19, 22, and 25 gauge. The Expect Flex is unique in that it only comes as a 19 gauge. The ProCore, SharkCore, and Acquire are FMB needles. These are available in 19, 22, and 25 gauge as well. Here is a pictorial description of the Expect and EchoTip FNA needles. The Expect Flex is unique in that it only comes as a 19 gauge and is made of nitinol. This allows for flexibility and passability. And it is more resistant to needle deformity, especially when you're going through tortuous anatomy. FMB needles. These include the Acquire, which is a Francine tip, the SharkCore, which is a Fork tip, and the ProCore, which is a reverse bevel core tip. Next, we describe the EUS liver biopsy procedure. Here we depict an ex vivo cadaveric liver undergoing EUS guided liver biopsy. The curvilinear echoendoscope is used to advance the FNA or FMB needle. The needle can be seen exiting the sheath prior to entry into the liver for actuation and tissue acquisition. There are six different suction techniques reported in the literature for EUS guided liver biopsy. For each suction technique described except slow pull, the needle should be introduced through the gastric or duodenal wall with a quick short stroke. The suction is then applied by opening the stopcock and the needle is passed into the liver. Several passes can be obtained. Before removing the needle from the liver, turn off suction by closing the stopcock. The first suction technique we'll describe is dry suction. With the echoendoscope in position inside the stomach or duodenum aiming towards the liver, the needle is attached to the biopsy channel of the curvilinear scope. The stylet is removed and the suction syringe with customizable suction between 5 to 20 cc's is attached prior to entry of the needle into the liver. The suction is turned on and upon puncture, one to three actuations are performed. The suction is turned off and the needle is withdrawn from the liver and locked. The next suction technique we will describe is slow pull. In this technique, the stylet is slowly and continuously withdrawn as the needle moves to and from within the target lesion. This creates minimal negative pressure to then absorb the biopsy specimen within the needle channel. The next suction technique we will describe is wet suction. In this technique, the stylet is removed. The needle is pre-flushed with roughly 5 ml's of saline to replace the column of air with fluid. A suction syringe with customizable suction between 5 and 20 cc's is attached to the needle and suction is then applied when the lesion is punctured. The next suction technique we will discuss is modified wet suction. In this technique, the stylet is first removed. The needle is then pre-flushed with 5 ml's of saline to replace the column of air with fluid. A suction syringe is pre-filled with 2 ml's of saline solution and the valve is closed. The syringe is then loaded to the 5 to 20 ml position with vacuum and then attached to the proximal port and used for biopsy when inserting the biopsy channel and puncturing the lesion. The next suction technique we will describe is wet heparin. This technique uses heparin lock flush solution which is being drawn up into the syringe. Here, the stylet is removed. The needle is pre-flushed with heparin until liquid droplets emerge from the needle. In the wet heparin technique, the needle is not air flushed. A suction syringe pre-filled with 2 ml's of saline solution is seen here. The syringe is then loaded to the 5 to 20 ml position with vacuum and then attached to the proximal port. This is used for biopsy when inserting into the biopsy channel and puncturing the lesion. The final suction technique is dry heparin. Again, we are using the heparin lock flush solution. In this technique, the stylet is first removed and the needle is again primed with heparin until we can see liquid droplets emerge from the needle. In the dry heparin technique, the needle is then flushed with air until no additional liquid is seen exiting the needle. Here we depict the air flush occurring twice to ensure the needle is free of liquid. The syringe is then loaded to the 5 to 20 ml position with vacuum and then attached to the proximal port and is used for biopsy when inserting into the biopsy channel and puncturing the lesion. Next let's put this together with an in vivo EOS liver biopsy. Here we are inserting the biopsy needle into the echo endoscope's working channel. The echo endoscope is then passed into the duodenal bulb to biopsy the right lobe or the gastric fundus to biopsy the left lobe. The needle is then introduced through the duodenal bulb or gastric fundus into the liver. Here we display the slow pull technique, however if a different suction technique would be used the suction syringe would be turned on prior to passing the needle. Demonstrated here in slow pull, the stylet is slowly and continuously withdrawn as the needle is passed to and fro in the target lesion. The needle is then withdrawn from the device in order to allow for tissue acquisition. The specimen can then be chased from the needle lumen with either fluid flushing of the needle or reinsertion of the stylet. The tissue is then directly expressed into formalin. The AASLD guidelines define an adequate liver specimen as one with a length of 15 millimeters and one with 11 or more complete portal tracts. Adverse events associated with EOS liver biopsy include sedation related adverse events, endoscopy related adverse events, and then FNA or FNB related events. These events include bleeding, abdominal pain, infection, or needle tract seeding of malignant cells. In summary, as EOS guided liver biopsy becomes more widely used, understanding biopsy needles and suction techniques is imperative. There is no consensus on superiority of needle and suction type as the evidence is currently conflicting.

EUS-guided liver biopsy

needle types

suction techniques

diagnosing liver diseases

acquiring tissue samples