Venogram - Uses, Types, and Procedure

Introduction:

A venogram is also called venography or phlebography, which uses a contrast agent and X-rays to visualize the veins in the body. This is commonly used in the diagnosis of venous abnormalities in the legs. This procedure uses contrast material to determine the flow of blood in the veins. The iodine-based solution is used as a contrast material in this procedure.

What Are the Uses of a Venogram?

A venogram is commonly used for the following purposes:

• Determine the status of the venous system.

• Deep venous thrombosis (formation of blood clots inside the deep veins).

• Congenital vein problems.

• Guiding tools in treatments such as placement of a stent in a vein.

• Helps in finding the suitable vein for bypass (veins from part of the body are attached to the coronary artery near the area of blockage).

• Detects varicose veins (swelling and twisting of the veins under the surface of the skin).

• Used to find the cause of unexplained pain in the legs.

How To Prepare for Venography?

• Before the procedure, a consent form has to be signed.

• Avoid eating four to six hours before the procedure.

• Keep the doctor informed about any medical conditions, surgical history, and medicines consumed on a regular basis.

• Inform the doctor regarding any allergic reactions to contrast material during the previous procedure.

How Is the Venogram Procedure Performed?

• For the venogram procedure, the physician may instruct to remove the clothes and wear a hospital gown and may ask to lie on the procedure table.

• Local anesthesia is given in the area where the needle will be inserted. They will put a mark on the parts of the body to locate the pulses. This procedure is often done on the leg.

• The nurse will clean the feet to make them sterile and insert the intravenous(IV) line or insert them into the veins of other parts of the body which they are going to look at. Saline water may be passed through the IV line to check for any blockages before injecting the contrast material. Then, they will inject the contrast material (a special dye) into the vein. A warmth is felt when the dye passes through the body.

• A tourniquet (tight band) is put on the part of the body, such as the arms or thigh, which makes the flow of contrast materials easily into deep veins on the part of the body to be visualized.

• Using fluoroscopy, X-ray images are taken when the contrast material passes through the legs and lower body. Patients might be asked to hold their breath at varying times for a few seconds to get better images. Intravascular ultrasound (IVUS) may be required sometimes to get detailed information on the blood clot and blockage inside the veins. Finally, the nurse will place a dressing over the puncture site.

This procedure usually takes about 30 minutes to one hour to complete. Regular activities and diet can be continued after the procedure. Avoid lifting heavy weights as it may strain the body or do aggressive exercises for five days after the procedure. Tell the physician if there is any discharge from the puncture site. Kindly drink plenty of water after the procedure to flush out the contrast material from the body.

What Are the Types of Venography?

• Ascending Venogram: In ascending venography, the tourniquets are placed just above the ankle and below the knee, which occludes the superficial system and directs the flow into deep veins. The catheter is inserted into the peripheral vein on the dorsum of the foot. In this procedure, 40 ccs of contrast material is injected. It is commonly used to locate deep vein thrombosis.

• Descending Venogram: Descending venography is a less frequently done procedure. In this procedure, a tube is inserted into the femoral vein at the groin. It is used to detect the function of the deep vein walls.

• Upper Extremity Venogram: This procedure is used to locate blood clots or abnormalities in the veins of the neck and arms. In upper extremity venography, the needle is inserted at the cubital vein at the elbow. It requires a low osmolar contrast medium of 300mgI/ml.

• Inferior Vena - Cavography: Inferior vena - cavography is used to determine the function of the inferior vena cava, which brings blood to the heart. 40 ml of contrast materials are injected in this procedure.

What Are the Limitations of Venograms?

• Diabetic patients who are taking Metformin or related medicines are advised to stop taking them 48 hours after the procedure as drugs may interact with contrast dye which causes metabolic acidosis (increased buildup of acid in the body).

• Radiation exposure in pregnant women causes birth defects in the fetus in the womb.

• Injection of contrast material in patients with diabetes and kidney disorders may worsen their condition. According to the American Academy of Family physicians, 0.1 to 13 percent of patients who had contrast material during the procedure might get kidney failure.

• Patients with severe swelling in the legs make the veins difficult to locate and visualize during the scan.

• Patients with congestive heart failure (a condition in which heart muscles do not pump the blood well) and pulmonary hypertension (a condition in which high blood pressure in the arteries carries blood to the lungs).

What Are the Risks of Venography?

The venography procedure involves some level of risk. The common risks are as follows:

• Swelling and infection at the injection site.

• Fever.

• Allergic reactions to contrast material. They are:

  • Headache.

  • Itching.

  • Nausea (urge to vomit) and vomiting.

  • Skin rashes.

Some of the severe symptoms of contrast materials are :

• Difficulty in breathing.

• Rapid heart rate.

• Low blood pressure.

• Swelling of the body parts.

What Are the Treatment Options for Venous Compression?

When the area of compression is found in the venogram, it may be treated by the following treatment procedures:

• Venoplasty - A medical procedure used to treat narrow veins. In this procedure, under local anesthesia, a special tube called a catheter with a balloon at the end is inserted into the veins. Once the balloon is placed near the narrowed position, the doctors will inflate the balloon, which stretches the narrowed veins. This procedure improves venous blood flow.

• Venous Stent - Under the guidance of the imaging technique, the stent (tiny, expandable tube) is placed in the narrowed veins through the catheter.

Conclusion:

A venogram is the gold-standard diagnostic tool for deep venous thrombosis. It is an effective imaging technique that can distinguish the blood clot in veins from venous obstruction. A venogram is a minimally invasive procedure in which radiation exposure is minimal. This procedure does not require hospitalization.