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DIAGNOSTIC X-RAYS (G I S E R I E S)
Flexible Sigmoidoscopy and Colonoscopy
Liver biopsy is a diagnostic procedure used to obtain a small amount of liver tissue, which can be examined under a microscope to help identify the cause or stage of liver disease.
What are the Different Ways a Liver Biopsy Can Be Performed?
The most common way a liver sample is obtained is by inserting a needle into the liver for a fraction of a second. This can be done in the hospital, and the patient may be sent home within 3 to 6 hours if there are no complications. The physician determines the best site, depth, and angle of the needle puncture by physical examination or ultrasound. The skin and area under the skin are anesthetized, and a needle is passed quickly into and out of the liver. Approximately half of individuals have no pain afterwards, while another half will experience brief localized pain that may spread to the right shoulder.
Another technique used for liver biopsy is guiding the needle into the liver through the abdomen or chest using various imaging techniques. This approach is used when there are localized tumors identified by ultrasound or computed tomography (CT). Either ultrasound or CT scanning is used to pinpoint the site of the tumor and guide the needle to this specific area through the abdomen or chest. After this procedure, the patient is usually allowed to go home the same day.
Less commonly used biopsy techniques are laparoscopy, transvenous or transjugular liver biopsy, and surgical liver biopsy. With laparoscopy, a lighted, narrow tubular instrument is inserted through a small incision in the abdominal wall. The internal organs are moved away from the abdominal wall by gas that is introduced into the abdomen. Instruments may be passed through this lighted instrument or through separate puncture sites to obtain tissue samples from several different areas of the liver. Patients who undergo this procedure may be discharged several hours later.
Transvenous or transjugular liver biopsy may be performed by a radiologist in special circumstances, e.g. when the patient has a significant problem with blood clotting (coagulopathy) or a large amount of fluid within the abdomen (ascites). For this reason, transjugular liver biopsy is recommended for patients with advanced cirrhosis. With this procedure, a small tube is inserted into the internal jugular vein in the neck and radiologically guided into the hepatic vein, which drains the liver. A small biopsy needle is then inserted through the tube and directly into the liver to obtain a sample of tissue.
Finally, liver biopsy may be done at the time a patient undergoes an open abdominal operation, enabling the surgeon to inspect the liver and take one or more biopsy samples as needed.
When is a Liver Biopsy Used?
Liver biopsy is often used to diagnose the cause of chronic liver disease that results in elevated liver tests or an enlarged liver. It is also used to diagnose liver tumors identified by imaging tests. In many cases, the specific cause of the chronic liver disease is highly suspected on the basis of blood tests, but a liver biopsy is used to confirm the diagnosis as well as determine the amount of damage to the liver. Liver biopsy is also used after liver transplantation to determine the cause of elevated liver tests and determine if rejection is present.
What Are the Dangers of Liver Biopsy?
The primary risk of liver biopsy is bleeding from the site of needle entry into the liver, although this occurs in less than 1% of patients. Other possible complications include the puncture of other organs, such as the kidney, lung or colon. Biopsy, by mistake, of the gallbladder rather than the liver may be associated with leakage of bile into the abdominal cavity, causing peritonitis. Fortunately, the risk of death from liver biopsy is extremely low, ranging from 0.1% to 0.01%.
In order to reduce the risk of bleeding, the coagulation status is assessed in all patients prior to a biopsy. If the prothrombin (coagulating) time is too slow or the platelet count is low, a standard biopsy is not recommended. Vitamin K or fresh frozen plasma may be used to correct clotting abnormalities in such instances. Another alternative in this situation would be a transjugular biopsy.
Are There Alternatives to Liver Biopsy?
The primary alternative to liver biopsy is to make the diagnosis of a liver disease based on the physical examination of the patient, medical history, and blood testing. In some cases, blood testing is quite accurate in giving the doctor the information to diagnose chronic liver disease, while in other circumstances a liver biopsy is needed to assure an accurate diagnosis.
Do Liver Biopsies Ever Need to be Repeated?
In most circumstances, a liver biopsy is only performed once to confirm a suspected diagnosis of chronic liver disease. Occasionally, liver biopsy is repeated if the clinical condition changes or to assess the results of medical therapy, such as drug treatment of chronic viral hepatitis with interferon or prednisone therapy of autoimmune hepatitis. Patients who have undergone liver transplantation often require numerous liver biopsies in the early weeks to months following the surgery to allow accurate diagnoses of whether the new liver is being rejected or whether other problems have developed.
Bringing the gut "up close and in color", and allowing specialists to examine every part of the digestive system is the way that endoscopy has been described by Dr. Peter Cotton, Director of the Digestive Disease Center.
Endoscopy is not a new procedure, having its origin in the late 1960s when it was used primarily as a diagnostic tool. Endoscopes are thin, highly flexible telescopes that allow specialists to examine most areas of the gut. Passed through the mouth under light sedation, endoscopes are used to explore the esophagus, stomach and small intestine, even the bile ducts and pancreas. Similar instruments are used from below to examine the colon. A variety of diagnostic and therapeutic tools can be used through the endoscopes. These include biopsy forceps, diagnostic needles, brushes, lasers, diathermy loops, balloons, baskets and stone crushers.
Many endoscopic procedures are now used routinely in the initial investigation of patients referred to the Digestive Disease Center at MUSC, where the endoscopy service is run by Dr. Robert Hawes, recently recruited from the University of Indiana. Upper endoscopy is the most accurate way of investigating patients with upper abdominal pain, difficulty in swallowing, nausea or vomiting. It is more accurate than barium meal x-rays in detecting inflammation, ulcers and tumors of the esophagus, stomach and duodenum. It can detect early cancer, and distinguish between benign and malignant conditions by taking small samples (biopsies) from suspicious areas. Once the diagnosis is made, upper endoscopy can be used to treat many of the conditions detected. Narrow areas can be stretched, polyps and swallowed objects can be removed, and gastrointestinal bleeding can be controlled. Endoscopic control of bleeding has reduced the need for transfusions, surgery and prolonged hospitalization in many patients.
Flexible sigmoidoscopy enables the physician to examine the lining of the rectum and lower part of the colon. Colonoscopy enables the physicians to probe further into the colon, allowing examination of the entire organ. This is frequently used for the detection and removal of polyps. These abnormal growths from the lining of the colon vary in size from a tiny dot to several inches. The majority of these are not cancerous, but all removed polyps are analyzed in the laboratory. The polyp may be destroyed by burning, or for larger polyps, a technique called snare polypectomy is done. A wire loop (snare) is passed through the colonoscope and severs attachment of the polyp from the intestinal wall by an electrical current. The importance of polyps is that they can develop into cancers if not removed in time. Colonoscopic polypectomy is therefore an important method for reducing the burden of colon cancer in the community when properly employed.
A special scanning device is fitted to the end of an endoscope, so that scans can be obtained from deep within the body. This provides more detailed diagnosis, particularly of smaller cancers. The hope is that detection of cancers at an early stage will increase the chance of cure. Another exciting new technique is enteroscopy, the examination of the whole of the long small intestine via an endoscope. This is particularly useful in patients with obscure bleeding in the small intestine, and inflammatory diseases such as Crohn's disease. Faculty and technical staff are also helping to develop new instruments to use with the endoscopes, and have an experimental laboratory to test the new equipment to make sure that it is safe before applying the benefits to patients.
A CT scan (also known as a "CAT scan," for "Computed Axial Tomography") is a diagnostic test that combines the use of X-rays with computer technology. A series of X-ray beams from many different angles are used to create cross-sectional images of the patient's body. These images are assembled in a computer into a three- dimensional picture that can display organs, bones, and tissues in great detail.
How do I prepare for this exam?
Do not eat solid food for three hours prior to the exam. You may drink clear liquids during this time. Routine medications may also be taken.
Abdominal/Pelvic Scan: We will schedule you to arrive one hour before your scan so that you will have time to prepare for the study. During this hour, you will be drinking oral contrast (dilute barium). Contrast is a liquid that improves the visibility of structures within the body.
If you are given barium to take home with you...
•Drink one bottle on the evening before the exam. •Drink one bottle one hour prior to the exam.
What happens in the CT room?
The CT scanner consists of a large donut-shaped machine and an X-ray table. You will lie on the table and be slowly moved into the large opening as a series of pictures are taken. You may be given an injection of IV dye (contrast) which improves the visibility of structures within the body. We ask that you lie very still and follow the instructions of the technologist while the scan is being performed.
Will it hurt?
No. There is no pain. CT scanning is a simple, safe method to "see inside your body."
How long will it take?
The exam will take between fifteen minutes and an hour from the time you lie on the CT table.
When may I eat?
As soon as the exam is over.
MRI (which stands for Magnetic Resonance Imaging) is the newest way to view the human body since the CT ("CAT") scanner was invented. Unlike CT scans, MRI does not use radiation in the conventional sense of the word. Rather, it combines the use of a large magnet and radio waves. The hydrogen atoms in the patient's body react to the magnetic field, and a computer anayzes the results and makes pictures of the inside of your body.
How do you prepare for an MRI exam?
You may eat and drink as usual, unless you are to have a scan of your abdomen or pelvis. Only then should you have nothing to eat or drink for 6 hours before your test. You should, in all cases, continue to take your medication. When you arrive for your exam, you will be asked to change into a hospital gown. Buttons, zippers, and other metal objects will affect the pictures. Please leave as much jewelry at home as possible. You should wear little eye make-up as this can affect the pictures also.
What happens in the scan room?
The MRI scanner consists of a large, donut-shaped magnet with a scanning table. The technologist (the person who takes the pictures) will position you on the table, and then move the table so that the area of interest is in the center of the machine's "tube." This tube remains open on the end; you are not "closed in." During the exam, you will hear a series of loud knocking sounds. You must remain very still at this time, as this is when the pictures are being taken.
Will it Hurt?
No. MRI is a painless exam. You will hear loud noises, however, so you may want to wear ear-plugs or headphones, which we can provide.
What should you do if you are claustrophobic?
The answer to this depends on how uncomfortable a small space makes you feel. If you have difficulty getting on an elevator, or dislike being in a room without windows, then you should call us in advance. The receptionist will either direct your call to a radiology nurse, or else will ask for some information about your appointment date and time, and how we can reach you. The message will be given to a nurse as soon as one is available. The nurse will call you back and help decide what is the best method for you to take the MRI exam.
How long will it take?
Each test is specifically tailored to your needs. Several pictures may be needed to complete the exam. Each picture can take anywhere from a few seconds to fifteen minutes. A full exam could take anywhere from twenty minutes to an hour and a half. The length of the exam depends on the area being tested.
No metal, please!
The presence of metal objects may affect the picture. Please be sure to inform the technologist or the radiologist if you have had any metal objects within in your body, such as pacemakers, aneurysm clips, or a prosthesis.
Bone scans are used to detect diseases of the bone at the earliest possible time. Bone scans are often more sensitive than x-rays in diagnosing infections, tumors, and fractures.
What does a bone scan entail?
You will receive an injection of a radioactive substance in a vein in your arm. This material travels through the bloodstream, into the soft tissue, eventually localizing in the bones. You will not feel anything from this injection. We may take some images during the injection to evaluate the blood flow to a particular area where you may be having pain.
The bone scan itself will be done three hours after injection. The scan takes 30-60 minutes. You will lie on your back on an imaging table. The camera will be positioned above and below you. The camera will scan the entire length of your body, starting at your head and moving slowly to your feet.
A SPECT (tomographic) study may be done to look at a particular area of your body in detail. This involves an additional 30 minutes of imaging while the camera rotates 360 degrees around you. In some instances X-rays may be needed to clarify bone scan findings.
Is any special preparation required before having a bone scan?
No special preparation is required before the bone scan. You will be asked to drink fluids in the three hours between injection and scan and to empty your bladder frequently. This helps to clear the injected material from your soft tissue and improves the quality of the bone scan.
How will I learn the results?
After the exam, the nuclear medicine physician will evaluate the images and discuss them with your physician. Your physician will explain the results to you.
How safe is this procedure?
Nuclear medicine procedures are very safe. The radioactive material is quickly cleared from your body. The radiation dose from this test (0.13 rem) is similar to most routine X-ray procedures.
Which parts of the body are examined by an abdominal ultrasound exam?
An abdominal ultrasound looks at the gallbladder, kidneys, liver, pancreas, and spleen. It also includes a view of the aorta and urinary bladder.
What happens during the exam?
The patient lies on a table with the abdominal area exposed. The sonographer (technologist who performs the exam) will put a warm water-based gel on the skin surface. The gel helps to transmit the sound waves by excluding air. An instrument called a transducer, which is about the size of a microphone, will be moved over the skin surface by the sonographer.
How do I prepare for this test?
Please do not eat solid food or drink anything but water for six to eight hours before the exam. Routine medications may be taken. If you are diabetic consult with your doctor.
How long will it take?
About twenty minutes.
Will it hurt?
No.
How will I learn the results?
You may call your doctor to discuss the results.
What is a GI series?
A GI or gastrointestinal series is an X-ray exam of the esophagus, stomach, and sometimes the small intestine that requires you to drink a liquid called barium.
How do I prepare for this exam?
It is important that you do not eat or drink anything from midnight the night before your exam. Also, do not eat or drink the morning of your exam. If your stomach is not empty the study will not be satisfactory or may have to be postponed.
Can I take my usual medication?
Essential medication may be taken with a sip of water. If you are diabetic, please consult your doctor before taking any medication on the morning of your exam.
What will happen in the X-ray room?
A radiologist and a technologist will be present. You wil be asked to swallow a mildly flavored barium drink. The barium mixture fills your stomach and small intestine so that they can be seen on X-rays. The radiologist will watch this on a special X-ray television screen. Periodically, the radiologist will ask you to change your position or hold your breath so that "snapshots" or spot films may be taken.
Will it Hurt?
No.
How long will the exam take?
The exam of your esophagus and stomach may take up to 30 or 45 minutes.
An exam involving your small intestine may take longer than two hours. This is unpredictable since it depends on how fast the barium moves through the small intestine. We wil take an X-ray every half hour to observe the movement of barium through the small intestine.
When may I eat?
You may eat as soon as the exam is over. You should drink plenty of liquids to avoid constipation form the barium. If instructed by the radiologist, you should take four tablespoons of a mild laxative such as milk of magnesia.
How will I learn the results?
The radiologist and your physician will discuss the results with you.
