An ultrasound is a noninvasive test that uses high frequency sound waves to produce a picture, and usually written on paper as US--short for ultrasound. There are a few types of ultrasounds: Conventional-which shows a flat picture, 3-D images, and 4-D which is 3D in motion. Doppler Ultrasound is a specialized technique that shows blood flowing through the veins and arteries. Ultra Sound can be used for several reasons which include visualizing organs, tissues, vessels, and tumors to detect any changes. It is also used to assist in needle guided biopsies, and to visualize the heart. The machine which is computerized can produce graphs and calculate numerical equations. The later is very important in relation to the heart.
A portable machine is brought to the bedside then the technician applies a clear gel onto the surface of the skin. The technician holds a transducer or the handheld device in their hand and runs it on the area where the gel was applied. The frequency waves produce a picture that is transmitted to a TV screen. The technician is able to save those pictures and print them out on paper for the doctor.
CT Scan or CAT Scan
“CT” Scan is short for Computed Tomography scan, and is also called a “CAT” Scan short for Computed Axial Tomography Scan. This is a sophisticated x-ray that takes multiple images of bone, blood vessels, and soft tissue. The computer then creates what is called “cross sections” or slices of the images. Normal x-rays cannot visualize or see the details that a CT scan can.
The procedure is painless and normally requires the insertion of an IV so dye can be injected allowing the machine to see the details of the soft tissue, bone, or blood vessel.
MRI stands for “Magnetic Resonance Imaging”. More sophisticated than a standard x-ray or even a CT Scan the MRI is a machine that uses magnetism, computer, and radio waves to produce the images the doctor wants to see. The images are created by the radio wave signals sent to the body that in turn forms a picture. The images are very accurate and specific. When completed it produces a clear and precise image of the organ, bone, vessel, etc.
A doctor may order the MRI with or without contrast. That largely depends on what the doctor is doing the MRI for. If contrast is ordered, then an IV is inserted in a vein and the contrast is injected to help with the visualization of the area the doctor wants to see.
Because the MRI utilizes a large magnet. patients are asked to fill out an MRI form. The reason is quite simple: If a person has a pacemaker, metal artificial joint, or other metal in the body the MRI may be cancelled. The magnet could cause the pacemaker to stop working for example. So the doctor and the technologist has to know if any of these things are present. The machine is actually a large tube that has a sliding bed that goes into it. The bed stays stationary but the hollow tube rotates around the patient. As the tube rotates it makes a knocking sound. This is how the picture is actually taken at every angle. The door is closed and sealed and then the process of the MRI begins. If someone is claustrophobic then it is recommended that they have what is called an “open MRI”. In an open MRI there is no door and the table slides into the hollow tube with both ends open.
The word “biopsy” is scary because we assume that it means cancer but that is not true. Biopsies are obtained to find out if an organ is diseased. So when a liver biopsy is ordered by your doctor it is because he/she suspects liver disease, not necessarily cancer. The biopsy is normally performed on an outpatient basis and doesn’t usually require a night in the hospital.
The procedure allows for a small piece of the liver to be obtained by the doctor who uses a special biopsy needle. A small incision is made and the needle is inserted into the liver. Then the needle is removed and the tissue in the needle is put in a sterile container and taken to the lab for analysis. Once in the lab the specimen is examined by the pathology lab under a microscope for any sign of damage or disease. A biopsy is a definitive test when looking for disease of an organ.
TIPS (Transjugular Intrahepatic Portosystemic Shunt)
The portal vein is a large vein that carries the blood from your intestines directly to the liver. Once the portal vein becomes hypertensive it causes the blood to flow backwards and sends it into the hepatic veins (the 3 veins that are supposed to carry the blood away from the liver.) The pressure becomes so great that the blood is being pushed up into the stomach, lower esphogus, and intestines. This causes the vessels to become enlarged; bleeding may occur (esphogeal varices), ascites (accumulation of fluid) in the abdomen, and fluid in the lungs. After these problems occur the decision may be made to have the TIPS procedure done.
TIPS is performed by a radiologist when there is an increase in the pressure of the portal vein (portal hypertension). When the radiologist performs the TIPS procedure it is done under what they call imaging (they can see the procedure as they are doing it on a TV screen.) The doctor makes a small tunnel into the liver to connect the portal vein to one of the hepatic veins. They insert a small metal tube called a “stent” into the tunnel to keep the path open. This will keep the blood flow going in the correct direction to and from the liver. Once the stent is placed it should reduce the pressure and hopefully eliminate the fluid buildup and bleeding from the varices.
Post Edited By Moderator (hep93) : 7/19/2009 4:54:31 PM (GMT-6)