Computed tomography of cerebral vessels
Imaging of the brain vessels is carried out for the study of blood, if necessary – and venous blood flow.
To better study small segments of the vascular bed, estimates of the parameters of blood flow, and cerebral blood flow should be used CT scan with contrast. For this purpose, iodine-containing means, which are administered intravenously (e.g., omnipak).
Computed angiography of the head is assigned in the following cases:
- frequent headaches of unspecified nature;
- if you suspect a stroke (and there are objective clinical manifestations of the disease);
- the suspected anomaly of cerebral vessels;
- in the presence of inflammatory processes in the vasculature;
- depression of consciousness (due to severe traumatic brain injury);
- for the differential diagnosis of volume processes in the brain (to determine the benign or malignant nature of the tumor);
- if you suspect compression of blood vessels by brain tumors;
- germination of walls of blood vessels malignant tumors (glial tumors of the brain, e.g., glioblastoma);
- before the planned surgery on the blood vessels (arteries or veins), for example, a stent;
- control in the postoperative period;
- to assess the effectiveness of treatment of malignant tumors (after radiation, chemotherapy or combination of methods);
- in cases where there are contraindications to performance of magnetic resonance angiography (e.g., pacemakers, or metal fragments in the patient’s body).
Computer contrast angiography of the vascular system of the head identifies:
- fresh ischemic lesions (within 2 to 24 hours after stroke);
- protrusion of the vessel wall (saccular aneurysm, and others);
- vascular malformations (congenital vascular abnormalities – arteriovenous malformation, venous angioma);
- the lumen of the vessels (e.g., narrowing due to atherosclerosis);
- pathological excesses, looping vessels;
- the germination of the vascular wall malignant;
- the ousting of the arteries and veins of the brain volumetric formations;
- build options for arterial and venous of the head;
- bleeding resulting from aneurysm rupture in the brain;
- thrombosis of the vessels of the head that caused a stroke.
It should be noted that case study can be evaluated: the structure of the vessel, the quality of the arterial and venous wall, the anatomical structure of the tissues surrounding the vessel, the presence of atherosclerotic plaques on the vessel walls and blood clots, the speed of propagation of a contrast agent.
Contraindications to CT, including in the study of cerebral vessels, associated with the use of ionizing x-ray radiation and the introduction of intravenous iodinated contrast.
In some cases, contraindicated performing CT of the vasculature with contrast agent:
- pregnancy (the study can be conducted for health reasons);
- it is not desirable to use in children (under 14 years);
- persons with intolerance to iodine;
- when kidney failure;
- if the patient is diagnosed with thyroid disease (e.g., thyrotoxicosis);
- in case of multiple myeloma and leukemia.
As practice shows, it is not necessary to conduct a CT scan to people who have located some metal objects in the study area. Patients whose body weight is greater than that which can withstand the tripod for the study (more than 140-150 kg).
Patient preparation for CT of the vascular system
Some special training is not required to be surveyed. It is recommended that at least 4 hours prior to the proposed study, not to drink and eat.
Don’t forget to warn medical staff if you have an allergic reaction to the iodine.
If the research is conducted nursing mother, in two days you cannot produce breast-feeding (should the milk pump).
Diabetes at the time you need to stop taking antidiabetic drugs (1 day before and day after the study).
If the patient has allergies to medicines, computed angiography should be carried out in the presence of an anesthesiologist, after preliminary examination.
The angiography of the vascular bed head
The statement briefly explains the essence of the procedure, warns that it is necessary to remove themselves jewelry (pins, earrings, bracelets, etc.). Helps in the correct position on the tripod for the study. Communication with nurses is carried out using a microphone.
Caution! If the introduction (I. V.) contrast agent have you had the following symptoms: nausea, fever, a metallic taste in the mouth, headache, immediately notify staff of the CT Cabinet.
Within half an hour after injection of contrast can also occur: skin rash, itching, shortness of breath, cough. These are all manifestations of an allergic reaction to iodine-containing drug. In this case, the medical staff immediately should give the patient first aid.
After a CT with contrast of the subject can quickly return to their usual business.
Computed tomography may be performed to children and pregnant women for health reasons, in cases where it is impossible to have magnetic resonance study. In this case the survey should be conducted on a multislice computed tomography without contrast enhancement, to cover the protective lead apron the pelvic area.
Quality computer tomograms can be bad if:
- the patient in the research process, moving head or torso;
- in the scanning area located metal objects, from which artifacts can appear;
- there is bleeding, however, as experience shows, the blood will obscure the adjacent organs, which prevents their visualization.
In conclusion, I want to emphasize the crucial role of multi-detector contrast CT in the evaluation of cerebral circulation in the first hours after the onset of clinical symptoms, detection of anomalies and malformations of the vascular system of the brain, as well as the detection of thrombi and atherosclerotic changes of the vessel walls.