The three main types of liver biopsy are percutaneous, transvenous, and laparoscopic. All three main types of liver biopsy remove liver tissue with a needle; however, each takes a different approach to needle insertion. Physicians may perform a liver biopsy at a hospital or outpatient center.
Percutaneous Liver Biopsy
The most commonly used technique for collecting a liver sample is percutaneous liver biopsy. For this method, a hollow needle is inserted through the abdomen into the liver to remove a small piece of tissue.
To help find the liver and avoid contacting other organs with the biopsy needle, physicians often use ultrasound, computerized tomography (CT), or other imaging techniques.
Ultrasound is an imaging technique that uses sound waves to create images of the body's internal tissues and organs. Ultrasound images are displayed on a video monitor. A physician chooses the best spot on the abdomen for inserting the biopsy needle and then marks the spot with ink. In other cases, Ultrasounds are used during a biopsy to safely guide the needle through the abdomen and into the liver.
CT is an imaging technique that takes hundreds of cross-sectional x-rays in a few seconds. Putting together the cross-sectional x-ray pictures—like lining up slices of a loaf of bread—a computer forms a whole image of the internal organ.
During the procedure, patients lie on their back on a table with their right hand resting above their head. A local anesthetic is applied to the area where the biopsy needle will be inserted. If needed, an IV tube is used to give sedatives and pain medication.
A physician will make a small incision in the abdomen, either toward the bottom of the rib cage or just below it, and insert the biopsy needle. Patients will be asked to exhale and hold their breath while the needle is inserted and a liver sample is quickly withdrawn. Several samples may be collected, requiring multiple needle insertions.
After the biopsy, patients must lie on their right side for up to 2 hours to reduce the risk of bleeding. Patients are then monitored an additional 2 to 4 hours after the biopsy before being sent home.
Transvenous Liver Biopsy
Transvenous liver biopsy is used when a person's blood clots slowly or when excess fluid is present in the abdomen, a condition called ascites.
During the procedure, patients lie on their back on an x-ray table and a local anesthetic is applied to one side of the neck. If needed, an IV tube is used to give sedatives and pain medication.
A small incision is made in the neck and a specially designed hollow tube called a sheath is inserted into the jugular vein. A physician threads the sheath down the jugular vein, along the side of the heart, and into one of the hepatic veins, which are located in the liver. To see the veins, your physician will inject liquid contrast material into the sheath. The contrast material lights up when x-rayed, highlighting the blood vessels and showing the location of the sheath.
Next, a biopsy needle is threaded through the sheath and into the liver; a liver sample is quickly withdrawn. Several samples may be collected, requiring multiple needle insertions. The sheath is carefully withdrawn and the incision is closed with a bandage.
Patients are monitored for 4 to 6 hours for signs of bleeding.
Laparoscopic Liver Biopsy
Laparoscopic liver biopsy is used to obtain a tissue sample from a specific area or from multiple areas of the liver, or when the risk of spreading cancer or infection exists.
Laparoscopic surgery is a technique that avoids making a large incision by instead making one or a few small incisions. During the surgery, physicians works with special tools—including a small, lighted video camera—passed through the incisions.
A physician may take a liver sample during laparoscopic surgery for other reasons, including liver surgery.
During laparoscopy, patients lie on their back on an operating table. An IV is inserted in a vein to give sedatives and pain medication. A small incision is made in the abdomen, usually just below the rib cage. A plastic, tubelike instrument, called a cannula, is inserted in the incision and the abdomen is inflated with gas. Inflation allows space for a physician to work inside the abdominal cavity.
A biopsy needle is inserted through the cannula and into the abdomen. The needle is inserted into the liver and a tissue sample is quickly withdrawn. Several samples may be collected, requiring multiple needle insertions. Any excessive bleeding because of the surgery is easily spotted with the camera and treated using an electric probe.
After liver samples are collected, the cannula is removed and the incision is closed with dissolvable stitches.
Patients will need to remain at the hospital or outpatient center for a few hours while the sedatives wear off.
