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CT angiography of the vessels of the abdominal cavity is considered one of the most modern methods for determining the state of health of the vascular system in this area. Its main difference is the involvement of a special contrast agent.
Conventional ultrasound is not able to provide a detailed picture of the structure and general condition of the vessels in the abdominal region, which contributed to the development and implementation of angiography technology. Together with the contrast, it turns out to visualize absolutely all parts of the vascular bed. Based on the visualization obtained, the doctor will be able to determine not only the structure of large and small vessels, but also to identify possible anomalies in nearby organs.
A detailed picture helps to detect even the slightest gaps, or to identify internal formations, whether they are oncological tumors or ordinary blood clots. Moreover, the image is so detailed that an experienced radiologist is able to recognize just emerging diseases based on it. The search for ailments at the initial stage of development for oncological diseases is especially relevant.
The main indications for the appointment
Against the background of numerous similar options, the computed tomography technique, adapted for the study of blood vessels, gives a much lower percentage of false information. This allows her to fix even tiny aneurysms that grow rapidly in a short period of time. A similar transformation of the splenic artery is characteristic.
Despite the stereotype, the traditional x-ray is generally not able to provide accurate data even on the state of large arteries and veins, which makes it completely useless for diagnosing abdominal vessels. In addition, the involvement of the X-ray machine exposes the patient’s body to radiation exposure. With angiography, the indicated irradiation parameter is an order of magnitude lower, which practically eliminates contraindications for its use.
There are many indications for attracting such an advanced technique. But almost all of them revolve around tumor-type diseases or the rapid development of inflammatory processes. Doctors also send their patients with congenital pathologies for diagnosis, who need regular health monitoring in order to adjust treatment programs in time.
If the patient was scheduled for a planned operation on the internal organs of the abdominal region, then here, too, one cannot do without passing such an examination. But the main reasons for receiving a referral to the diagnostic room are the following diseases and assumptions:
- aneurysms of varying severity;
- stenosis;
- occlusion caused by neoplasm pressure, adhesions or scarring after surgery;
- thrombosis;
- pain in the abdomen of unknown etiology;
- atherosclerosis not only of the abdominal aorta, but also of its branches;
- metastases from a malignant tumor in the para-aortic lymph nodes or mesentery;
- growth of tumors inside the vessels;
- any anomalies of the vascular network;
- aortic dissection.
Also, before discharge from the hospital after surgery on the abdominal organs, the attending physician may refer the patient for a second examination. This will make sure that the assistance went without complications.
Patients suffering from deviations in the functioning of the liver deserve special attention. If they were previously diagnosed with a tumor lesion, or there is a suspicion of such a diagnosis now, then this is a reason to go for a CT scan. There is also a direct road for those who have found fatty hepatosis, cysts, abscesses of any origin and cirrhosis at different stages.
If an enlarged liver was found in a patient using a classic ultrasound, and there are no significant prerequisites for this, then it is possible to find the cause using a CT scan of the abdominal vessels.
Even pathologies that affect the functionality of the biliary tract are studied through angiography. This also included ailments closely related to interruptions in stable work:
- pancreas;
- kidney;
- ureters;
- spleen;
- adrenal glands.
Any damage and injury to the abdominal organs should also be studied using a modern imaging method. The reason for this is the frequent cases of internal bleeding, which are difficult to recognize without examination.
Sometimes the doctor who sends the patient for this type of CT scan is a vascular surgeon or cardiologist who suspects hypertension, thrombosis of the portal or inferior vena cava. And if damage to the aorta and its nearest branches is detected, an emergency operation is usually immediately prescribed.
When is angiography not recommended?
The most significant contraindication for using CT as a diagnostic tool is pregnancy at any time. The reason for such a categorical ban is radioactive radiation. Despite the fact that its dosage with short manipulation is safe for an adult, this does not apply to the fetus. Ignoring advice can backfire with deviations in the mental and physical development of the unborn baby. Because of this, doctors prefer to prescribe alternative diagnostic options for women in an interesting position.
Things are a little easier with the lactation period. Here you can get by with small losses – just refuse to breastfeed for about two days after the procedure. This is explained not only by the weakening of radioactive radiation, but also by the timing of the complete elimination of the components of the contrast agent.
Just because of the peculiarities of the composition of the contrast agent, the following significant contraindication emerges – individual intolerance or an allergic reaction. Usually, various iodine combinations are used as a contrast agent. If the patient knows for sure that he is allergic to pure iodine or seafood in particular, he should warn the doctor about this in advance.
If the patient has never experienced anything like this before, but doubts that he will be able to tolerate a dose of iodine in the blood without consequences, then he is prescribed an additional allergological test. With a positive result, there are two options:
- replace the base of the solution with other components;
- combine a standard drug with antihistamine drugs.
The choice in favor of one thing is made by the doctor on the spot, taking into account the characteristics of the organism of the subject.
All other contraindications from the list are relative. This means that if the benefit of the analysis outweighs the possible side effects from its use, it will still be prescribed. The list includes:
- Thyroid gland diseases;
- kidney disease;
- diabetes;
- myeloma;
- claustrophobia;
- hyperkinesis and involuntary spasms, convulsive syndrome;
- children up to 5 years;
- weight over 150 kg.
The kidney failure on the list is here due to the fact that in order to quickly remove the contrast components, the kidneys have to work in an enhanced mode. If they cease to cope with the tasks assigned to them, then the elements of the drug will turn into toxins that will be deposited in the tissues.
Claustrophobia, which is the inability to be in an enclosed space, is also a relative contraindication. Some people are ready to step over their fears, since they will only have to spend about ten minutes under the arch with detectors. But if the patient still develops an attack, then he will be given a sedative medicine to stabilize the emotional background.
All the problems here come from the fact that a person cannot move while under the scanner, otherwise they will have to redo everything again. Babies, like people with involuntary convulsions, are unlikely to be able to control themselves. Hence the logical counter-indication. But under emergency circumstances, they can be introduced into the phase of drug-induced sleep.
With regard to weight, here the body weight limit is calculated based on the distinctive features of a particular equipment. Some devices can only withstand weight up to 120 kg, but modern models have extended the figure to 150 and even sometimes up to 200 kg.
Preparatory stage and technology
No one will require significant preparation from the subject. The doctor will only warn that during the scan, the device will emit loud beeps, and you should not be afraid of them. Also, before contrasting, you will need to refrain from eating and drinking approximately four hours before the start of the diagnostic event.
After the patient removes all metal objects and lies down on the medical couch, the X-ray laboratory assistant will start the scanner.
When a contrast agent is injected, people sometimes feel a sensation of heat or cold that spreads through the body along the course of blood flow. This is considered within the norm.
The manipulation itself lasts from ten minutes to half an hour, which depends on the type of apparatus and the characteristics of the action of the contrast. All this time the patient must be in a horizontal position, remaining completely motionless. Since even adults cannot always maintain one position for a long time, auxiliary straps were provided on the couch for the convenience of the subjects. And they put a cushion under their heads.
But if during the study something still went wrong, the patient will be able to contact the medical staff through feedback. Each modern device has a microphone on the patient’s side.
All incoming information is instantly transferred to the computer’s memory, which is necessary for building a visual reconstruction in a three-dimensional form.
As soon as the study comes to an end, the doctor will advise you to start drinking more fluids to speed up the elimination of the harmful components of the contrast agent.
Many patients are pleased with the fact that the examination is absolutely painless. But it is worth preparing for the fact that some of the subjects, due to the contrast, have a feeling of nausea and a headache. These are quite common phenomena, as is a slight redness near the injection site.
What does hagiography provide?
After the contrast agent is injected into the cubital vein, it instantly reaches the heart and then spreads along the aorta, its branches, and later to the capillaries in the peritoneum, revealing a picture of the condition:
- renal vessels;
- splenic vessels;
- intestinal trunk;
- superior mesenteric artery;
- inferior mesenteric artery.
All of them, like capillaries, are responsible for transporting nutrients to the internal organs of the abdominal cavity. As soon as these blood pathways fail, the body ceases to perform its duties properly, which leads to a sharp deterioration in well-being. Careful visualization allows you to find the source of all problems, on the basis of which you can find out the following characteristics:
- anatomical features of the abdominal vessels, regardless of size;
- anomalies of a congenital or acquired type, up to doubling and underdevelopment;
- pathologies at different stages of development, including local atherosclerosis and stratification of the walls;
- the percentage of the degree of vascular constriction;
- indicators of blood flow disorders;
- description of the blood flow, including the rate and level of blood filling.
All this describes radiologist, who, in case of emergency, can give a detailed report to the patient himself approximately half an hour after the test. And the attending physician himself, on the basis of the results obtained, complaints, the results of other examinations, anamnesis data, such as, for example, hereditary predisposition, draws specific conclusions. In addition to determining the final diagnosis, the attending physician also prescribes subsequent therapy, including conservative methods and / or surgical intervention.
If a particularly large area of the lesion is found, which is characteristic of exfoliating aneurysms and vein thrombosis, the operation is prescribed urgently to save the patient’s life.
Some doctors continue to send their patients for routine CT scans the old fashioned way. But only angiography is adapted for measuring the state of blood vessels with moving blood and constant pulsation. Movement inside the body does not prevent it from capturing control sections at all, transmitting high-resolution layered images.