Phlebography
Phlebography is a radiological test used to obtain images of the veins in a specific area of the body in order to diagnose vascular diseases.
General Description
Phlebography is a diagnostic test used to obtain images of the veins. It is a radiological technique that uses X-rays and iodinated contrast to visualize blood flow within the vessels, as veins are not visible on a conventional radiograph.
Depending on how the contrast medium is administered to opacify the veins and make them visible on imaging, phlebography is divided into two types:
- Indirect phlebography: the contrast is injected into the artery supplying blood to the area whose veins are to be studied.
- Direct phlebography: the contrast is administered directly into the veins. There are two techniques:
- Ascending: the substance is injected in the same direction as blood flow (on the dorsum of the hand or foot). This is commonly used in studies of both lower and upper extremities.
- Descending: the catheter delivering the contrast is positioned against the direction of blood flow (in the groin).
When is it indicated?
Phlebography is typically performed to diagnose venous diseases, particularly in cases where Doppler ultrasound has not provided conclusive findings.
This procedure is especially useful for obtaining information about the deep veins of the legs or those located in the pelvis. It is used to diagnose varicose veins, thrombosis, congenital defects, or phlebitis.
Phlebography is contraindicated in pregnant women, as radiation may harm the fetus, and in individuals with allergies to contrast material.
How is it performed?
Once the patient is positioned on the examination table, typically in the supine position (lying on their back), local anesthesia is administered. A catheter is then inserted into a superficial vein or an artery to inject the contrast medium.
Finally, the patient is placed between the X-ray source and a special plate that captures the images. The specialist ensures that the images are not blurred and that all venous details are clearly visible before concluding the procedure.
Risks
Although phlebography is a safe technique, some patients may experience side effects caused by the contrast medium:
- Dizziness
- Nausea
- Vomiting
- Itching
- Cough
- Headache
In rare cases, an allergic reaction to the contrast material may occur, potentially leading to respiratory difficulties, arrhythmia, or anaphylactic shock.
The radiation received during phlebography is minimal and does not have significant health effects (although it may affect the unborn).
What to expect from phlebography
Phlebography is an outpatient procedure after which patients can return home following approximately six hours of rest in the observation area. As it is a radiological test, patients must enter the room without metallic objects and wear the gown provided by the medical center. Informed consent must be signed beforehand.
Once in the radiology department, the patient is positioned on the table to allow optimal access to the veins being studied. Restraint systems may be used to secure the patient to the table and prevent movement, especially if tilting is required to obtain images from different angles. A catheter is then placed, either in a vein or an artery, through which the contrast will be administered. In some cases, local anesthesia may be necessary to minimize discomfort, particularly if an incision is required for catheter insertion.
The patient must remain still throughout the procedure, which involves the controlled emission of X-rays that pass through the body and are recorded as images on a plate. At the end of the procedure, the catheter is removed and a bandage is applied over the incision, which can be removed the following day.
Once at home, it is recommended to rest the limb where the puncture was performed. The incision site should be monitored to prevent bleeding. If pain, warmth, numbness, or redness of the skin in the area is observed, the patient should seek emergency care to rule out thrombosis. Drinking plenty of water is recommended to help eliminate the contrast medium more quickly.
Phlebography typically lasts between 15 and 30 minutes, and results are usually available within a few days during a follow-up consultation.
Specialties in which phlebography is requested
Phlebography is a test used in the specialty of Angiology and Vascular surgery and in the Cardiovascular risk unit.
How to prepare
Patients must fast for at least six hours prior to the procedure. Additionally, certain treatments may need to be temporarily discontinued, particularly anticoagulant medications.
