In 21st century medicine, increasing attention is being paid to visualization methods of internal organs, including blood vessels. X-ray methods also lend themselves to constant changes and improvements, images of organs become more detailed and clear. And the beginning of the use of contrast made it possible to see the shape and size of blood vessels and tubular organs. One of these methods is phlebography, or venography.
Phlebography - what is it?
Phlebography is an X-ray method for examining veins by introducing contrast, the passage of which through the vessel is accompanied by constant monitoring by a radiologist. Contrast is a special solution that is injected into the patient’s peripheral vein. It is thanks to him that you can see the location, shape of the vessels, the presence of blood flow in them.
Types of phlebography
Depending on the method, the venography of the veins of the lower extremities is divided into two main types: ascending and retrograde. Ascending is used to determine the shape, size, location of venous vessels.
Retrograde venography is used to examine the valves that are in the venous vessels. The peculiarity is that it is held with a breath hold. At the same time, valves that do not have defects in their work delay the contrast, and those that have any violations pass the contrast in the opposite direction.
Indications for
Phlebography is a research method that is used for venous disease. It is mainly used in the pathology of veins of the lower extremities, pelvic organs. The main diseases requiring radiopaque phlebography include:
- varicose veins with mixed results of functional tests, which are carried out primarily in the diagnosis of varicose veins;
- postthrombophlebitis syndrome;
- recurrent varicose veins of the lower extremities;
- acromegaly (an increase in limbs due to increased production of growth hormone of the pituitary gland) in order to visualize the venous system of the legs;
- trophic ulcers as a result of varicose veins;
- as a control for sclerotherapy.
Contraindications
Since phlebography is a radiopaque and invasive research method, there are a number of contraindications to its use. Moreover, a person may encounter conditions that prohibit the introduction of contrast, and those that exclude the use of x-rays in principle.
The main contraindications include:
- An allergic reaction to contrast. In most cases, an iodine-containing contrast agent is used, and if the patient is allergic to iodine, the contrast can be replaced by gadolinium.
- Chronic diseases in the stage of decompensation.
- Acute infectious diseases.
- Renal or liver failure in a severe stage. With these pathologies, it is difficult to remove the contrast agent from the body.
- Pregnancy is a contraindication to any x-ray examination, since x-rays adversely affect the fetus.
- Conditions in which bleeding with the introduction of contrast is possible: hemophilia, thrombocytopenic purpura.
- The presence of inflammation in the area of trophic disorders.
- Senile age (relative contraindication).
The essence of the method
The presence of contrast, which fills the veins and is visible under the action of x-rays, allows the radiologist to see the shape and location of the veins, the presence of a defect in them, a violation of blood flow, which the specialist will describe as a “defect in filling of the contrast."
What can be seen with phlebography of the veins of the lower extremities and the pelvis? It allows you to diagnose:
- the presence of an embolus in the veins;
- clotted veins;
- anomalies in the structure of blood vessels of both congenital and acquired origin;
- violations in the work of venous valves, their patency, diameter;
- quantity and structure of communication veins.
In most cases, phlebography is not a diagnostic method of choice, it is carried out after unclear and doubtful results of non-invasive examination methods. It is used not only for diagnostics, but also as one of the preparatory methods before surgery. For example, to visualize a vein before shunting it.
To reduce the radiation load on the patient, it is possible to use a large-frame fluorograph, which allows you to reduce the procedure to one minute, making up to 9 images during this time.
Examination preparation
Since the method is invasive (using x-ray irradiation), phlebography of the lower extremities requires careful preparation. The main activities are as follows:
- Refusal of food at least 4 hours before phlebography; drink only water.
- Before the administration of the contrast agent, an allergic test is carried out for 1-2 days by subcutaneous administration of 0.1 ml of contrast and followed by monitoring the skin reaction. The presence of any signs of allergies (itching, rashes, redness) is a contraindication to the introduction of iodine-containing contrast medium.
- A few days before the examination, a coagulogram (determination of blood coagulation), a general analysis of blood and urine, an electrocardiogram are performed.
- Right before the procedure, the patient should empty the bladder, completely undress and put on a hospital gown.
- With a strong fear of the procedure and patient anxiety, the doctor may prescribe sedatives to him.
- If pain occurs during the procedure, the patient is given sedatives or analgesics.
Methodology
How do phlebography? Location of the patient in the X-ray room: horizontal, on the back, on a hard surface. Nothing should be under your feet, they should lie flat and motionless. Next put a tourniquet on the ankle for better introduction of contrast.
After applying the tourniquet, an injection of novocaine solution is performed to relieve vasospasm. Next, the X-ray table is installed in a vertical position and the physiological solution is injected into the dorsal artery of the foot, followed by the slow introduction of contrast for 1-1.5 minutes. If it is not possible to puncture a vein, then make a small incision (venesection). The doctor should warn the patient about possible reactions to the introduction of contrast: nausea, burning, dizziness, etc. If they occur, the patient should immediately inform the doctor.
When contrast is introduced, the radiologist monitors the spread of the contrast medium through the veins and takes the necessary pictures. When the result is obtained, a special solution is introduced to remove the contrast. Only when the fluoroscopy shows that the contrast is completely removed, the observation is stopped and the needle is removed.
At the end, it is necessary to apply a pressure bandage on the limb at the site of contrast injection and wrap the leg with an elastic bandage. The doctor should warn the patient that he should not move his limb over the next couple of hours.
Possible complications
As a rule, venography of the veins of the lower extremities is successful. However, sometimes undesirable side reactions and complications may occur:
- inflammatory diseases at the injection site (abscess, skin phlegmon);
- inflammation of the venous vessels (phlebitis);
- allergic reactions to the administration of a contrast agent - from the lungs (urticaria, redness of the skin, itching) to severe (anaphylactic shock, Quincke's edema);
- development of renal failure;
- bleeding disorders (the formation of blood clots and blockage of blood vessels);
- a patient with acute viral diseases may worsen.
Pelvic vein venography
Although the majority of phlebography is associated only with the diagnosis of pathology of the veins of the lower extremities, it is also used to detect blood flow disorders in the veins of the small pelvis. Most often it is used in gynecology. It allows you to evaluate the veins of not only the pelvis, but also the venous channel of the uterus. The method allows you to diagnose the expansion of veins of the first degree, a characteristic feature of which is a corkscrew course of blood vessels.
Pelvic dilatation is an early sign of valve failure long before any symptoms appear. If you do not diagnose the expansion or ectasia of the veins in time, then varicose disease or the expansion and inflammation of hemorrhoidal veins may develop.
Modern methods of phlebography
Medicine is improving every day, including phlebography. One of such modern methods is CT phlebography. Although this method also applies to radiological, it is more perfect. The main advantages of CT venography:
- It is carried out using a special apparatus - a tomograph, which makes it possible to more accurately visualize blood vessels and immediately take a large number of images from different angles;
- three-dimensional image allows you to view vein in detail from different angles;
- less radiation exposure due to a more advanced computed tomography mechanism;
- does not require hospitalization of the patient in a hospital and further observation.
CT venography does not allow you to see the change in veins in the dynamics, however, it helps in the diagnosis of damage to the veins of the pelvis, retroperitoneal space, chest. Another highly effective method for visualizing veins is MRI phlebography.
MRI venography: features
The main advantage of this method of examining veins is the possibility of conducting it in patients with an allergy to iodine-containing contrast agents, since it is possible to conduct MRI venography without using contrast.
Also, this research method excludes radiation, as it is not radiological. The essence of MRI is the reaction of the electromagnetic field to the concentration of hydrogen ions in the tissues. Since different tissues contain different amounts of hydrogen ions, they will also be visible on MRI with different colors. The main contraindication is the presence in the body of any metal objects (pacemaker, prosthetic joints, clips on the vessels).
Venography Results
With the normal structure of the vessels and the absence of their pathology, phlebography of the veins of the lower extremities shows that the dye quickly and uniformly fills the lumen of the vessel. If filling with contrast slows down or stops altogether, or if a filling defect is observed, then the patient may have an obstruction of blood flow through the venous vessels (thrombosis, embolism).
Currently, traditional radiopaque venography is being used less and less, giving way to more modern examination methods: CT, MRI, and ultrasound examination of blood vessels. However, phlebography is a method that is still widely used in many medical and diagnostic centers due to its accessibility and low cost.