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Diagnostic venograms
Venograms, or venography, are a subset of a larger class of X-ray exams called angiography. Angiography in general is the X-ray study of the blood vessels in your body. Venograms deal strictly with the veins as opposed to the arteries, most commonly the veins in your legs, though other sets of veins can be examined. These studies are generally done when your doctor has reason to suspect a blood clot or other blockage of one of the more important vessels.
Since blood vessels in general do not show up on X-rays, a "dye" or contrast media must be injected into the veins being studied. This contrast medium is an organic iodine solution, meaning that the iodine is bound to compounds similar to those found in living organisms. While venograms can be done of just about any part of your body, they all are done using a similar style,and venograms of the leg are the most common.
When doing a venogram of the leg, the radiologist and technologist doing your study will have you remove your pants, shoes, and socks, and put on a hospital gown. You will then be placed on an X-ray table that has been tilted up to between 30 and 45 degrees. Two tourniquets will be placed around your leg, one down near the ankle, and one up high on the thigh. These tourniquets are not to stop the blood flow in your leg, but rather to slow it down so that adequate x-rays may be obtained. The radiologist will then start an IV in your foot and slowly inject the contrast medium into it while the technologist quickly takes a series of films. Another common version of this exam will have the technologist injecting the contrast through the IV in the foot while the radiologist films the study using fluoroscopy. The advantage to this method used at Emory is that we can do a "subtraction" study, where a computer uses a special "mask" or filter to remove from the X-ray images everything except the veins being studied and the outlines of the major bones that can then act as land marks to identify where any problem areas may lie.
Pulmonary arteriogram
The purpose of a pulmonary arteriogram is to diagnose a blood clot in the pulmonary circulation. The procedure time is 30 to 45 minutes. The procedure goes as follows:
- Patient is taken to IPU to be shaved, prepped, get IVs and have labs drawn. The physician or radiologist will access the femoral vein, a catheter will be placed in the right and left pulmonary arteries and a series of pictures will be taken during contrast injections.
- Pulmonary pressures could be measured before X-rays are taken.
- The sheath will be removed and pressure held at the femoral stick site for 10-15 minutes. A Band-aid will be applied.
- Patient will be on bed rest for 4-6 hours after the exam.
- Patient must have someone drive them home.
Embolization of pulmonary arteriovenous malformations (AVM)
This is the closing of vascular structures by transcatheter approach or percutaneous puncture using liquid or particles to shut off, or embolize, the area. The procedure is used for :
- Treatment of hemorrhage.
- To correct malformations in arteries or veins(AVM) and fistulae in arteries or veins.
- Organ or tumor ablation.
Your physician and radiologist will determine the methods and materials to conduct the embolization procedure. Often the best embolization material can only be selected after careful angiographic evaluation.
Venous sampling including renal, adrenal and petrosal veins
Venous sampling is selective or super-selective catheterization and aspiration of blood samples from veins draining an organ or tumor of interest. Examples include measurement of hormone secretion in tumors of the pancreas, the adrenals, or parathyroid glands; search for increased renin levels in the renal vein in arterial hypertension; measurement of increased hormone levels in the ovarian veins; and sampling via the jugular vein in cases of ACTH-producing tumours.
Transhepatic portosystemic shunt (TIPS) placement
The management of portal hypertension has undergone significant changes in the last two decades, with advances in medical, endoscopic and interventional radiologic treatment options. Many methods have been incorporated in reducing the portal venous pressure, for treating the serious and life threatening complications of advanced liver disease. Since its introduction over a decade ago, the TIPS placement has become a fundamental treatment option.
In its most basic form, a TIPS is a percutaneously created shunt spanning the liver's portal and hepatic veins. The shunt is built inside the liver using interventional radiological techniques. This conduit shunt has far less morbidity and mortality, and has replaced the surgical shunt in most centers throughout the world.
To date, more than 70,000 TIPS have been created in the last 13 years, a meteoric rise compared with the number of surgical shunts performed in that therapy's 60-year history. It is expected that the number will increase as the worldwide incidence of hepatitis C related cirrhosis continues to grow.
Transcatheter liver biopsy
Transcatheter liver biopsy is an elegant method of performing liver biopsy in patients with massive ascites and/or prolonged prothrombin time, both common occurrences in liver disease. The technique can also be extended to diagnose and angiographically treat Budd Chiari syndrome when this abnormality is encountered during a transjugular liver biopsy.
Indications include:
- Presence of massive ascites
- Presence of massive obesity
- Severe coagulopathy
- Failed percutaneous biopsy
- Suspected vascular tumor or peliosis hepatitis
- Need for ancillary vascular procedures (TIPS, venography)
Contraindications: There are no major contraindications. Thrombosis of the internal jugular vein is a relative contraindication. Uncooperative and pediatric patients may require anesthesia. The angulation of the right hepatic vein with the IVC might be acute and hinder access with the metallic cannula.
Venous access including catheter declotting
Central venous access devices are small, flexible tubes placed in large veins for people who require frequent access to the bloodstream. Central venous access devices are often referred to as venous access ports or catheters, because they allow frequent access to the veins without deep needle sticks.
Placement is usually in one of the large veins of the chest or neck, although placement can also be in the groin, if necessary. Venous access devices typically remain in place for long periods: weeks, months, or even longer. Venous access devices are most often used for the following purposes:
- Administration of medications - Antibiotics, chemotherapy drugs, other IV drugs.
- Administration of fluids and nutritional compounds.
- Transfusion of blood products.
- Multiple blood draws for diagnostic testing.
Venous access devices provide several advantages over regular IV lines, which are usually inserted in a small vein in the hand or arm. Venous access devices avoid problems that result over time from administering strong medications through small veins with regular IV lines, namely irritation of the vein and blood clots in the vein.
A central venous device also avoids the inflammation and scarring that can occur in a vein after multiple needle sticks. A central access device increases comfort and reduces anxiety for people who require frequent venous access. Venous access devices that can be implanted under the skin were introduced in 1982. They allow medications to be delivered directly into larger veins, are less likely to clot, and can be left in for long periods.
Port placement (arm and chest ports)
The outcome of a port is to provide intermediate to long-term central venous access in a safe aseptic manner. This includes both arm and chest ports.
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