LAB TEST
Renal venogram
A renal venogram is a test to look at the veins in the kidney. It uses x-rays and a special dye (called contrast). X-rays are a form of electromagnetic radiation like light, but of higher energy, so they can move through the body to form an image. Structures that are dense (such as bone) will appear white and air will be black. Other structures will be shades of gray. Veins are not normally seen in an x-ray. That is why the special dye is needed. The dye highlights the veins so they show up better on x-rays.
How the Test is Performed
This test is done in a health care facility with special equipment. You will lie on an x-ray table. Local anesthetic is used to numb the area where the dye is injected. You may ask for a calming medicine (sedative) if you are anxious about the test. The health care provider places a needle into a vein, most often in…
How to Prepare for the Test
You will be told to avoid food and drinks for about 6 hours before the test. Your provider may tell you to stop taking aspirin or other blood thinners before the test. DO NOT stop taking any medicine without first talking to your provider. You will be asked to wear hospital clothing and to sign a consent form for the…
How the Test will Feel
You will lie flat on the x-ray table. There is often a cushion, but it is not as comfortable as a bed. You may feel a sting when the local anesthesia medicine is given. You will not feel the dye. You may feel some pressure and discomfort as the catheter is positioned. You may feel symptoms, such as flushing, when the…
Why the Test is Performed
This test is not done very often anymore except in the treatment of varicose veins of the testicles or ovaries. Otherwise, it has largely been replaced by CT scan and MRI. In the past, the test was used to measure levels of kidney hormones. Rarely, the test may be used to detect blood clots , tumors , and vein…
Normal Results
There should not be any clots or tumors in the kidney vein. The dye should flow quickly through the vein and not back up to the testes or ovaries.
What Abnormal Results Mean
Abnormal results may be due to: Blood clot that partially or completely blocks the vein Kidney tumor Vein problem
Risks
Risks from this test may include: Allergic reaction to the contrast dye Bleeding Blood clots Injury to a vein There is low-level radiation exposure. However, most experts feel that the risk of most x-rays is smaller than other risks we take every day. Pregnant women and children are more sensitive to the risks of the…
References
Bechara CF. Venography. In: Sidawy AN, Perler BA, eds. Rutherford's Vascular Surgery and Endovascular Therapy . 10th ed. Philadelphia, PA: Elsevier; 2023:chap 28. Perico N, Remuzzi A, Remuzzi G. Pathophysiology of proteinuria. In: Yu ASL, Chertow GM, Luyckx VA, Marsden PA, Skorecki K, Taal MW, eds. Brenner and…
This is a summary. Read the full article at www.ucsfbenioffchildrens.org (reviewed 29/01/2024).
This page is general information and is not medical advice. It does not replace a registered doctor, and it is not a prescription or a recommendation to use any medicine or test. Prices are listed prices and may change. Always follow the advice of your doctor or pharmacist.