Ultrasound of head and neck vessels is a non-invasive diagnostic method that visualizes the carotid and vertebral arteries, neck veins, and the main arteries of the brain. It is used in the diagnosis of vascular atherosclerosis, stroke, stenosis, thrombosis, embolism. Ultrasound of the vessels of the head and neck consists of several procedures: transcranial dopplerography, ultrasound of the vessels of the head, ultrasound and ultrasound of the vessels of the neck.
Special preparation for ultrasound of the vessels of the head and neck is not required. General recommendations before scanning are as follows:
- The day before the examination, you should give up coffee, strong tea, alcoholic and energy drinks.
- Do not smoke two hours before the procedure.
- Warn the doctor about taking medications that affect vascular tone (hypotensive, vasoconstrictive).
Ultrasound of head and neck vessels visualizes the state of the arteries and veins located outside and inside the skull, along the course of the brain stem and the cervical spinal cord. Transcranial Dopplerography determines the patency of the veins and arteries of the head. Duplex examination of the vessels of the head reveals the speed of blood flow, the cause of vascular patency disorders. Ultrasound Dopplerography of the neck vessels provides information about the blood flow of the basilar, vertebral and carotid arteries. The structure of the arterial and venous chains is visualized with the ultrasound of the cervical vessels, the rate of venous outflow and blood flow along the basilar artery is determined.
Normally, the thickness of the walls of the arteries is 0.9-1.1 mm, the diameter of the vertebral artery is not more than 2 mm, the lumen of the vessels is free, there is no turbulent blood flow and vascular branching, the blood flow rate in the veins is 0.3 m / s (small deviations are acceptable). With the help of ultrasound , the following pathologies are detected:
- Atherosclerosis. With non-stenosing atherosclerosis of the artery, an increase in the walls, uneven echogenicity, narrowing of the lumen by 20% or less is detected. Another characteristic sign of atherosclerotic lesion is the wrong course of blood vessels, the presence of tortuosity and kinks.
- Vascular stenosis. The key manifestation of vascular stenosis is a decrease in the diameter of veins, arteries, narrowing of the lumen.
- The presence of blood clots. The ultrasound method determines the presence of plaques, blood clots. With complete obturation of the vessel, there is no lumen, with partial – it narrows (the doctor assesses the degree of narrowing).
- Abnormalities of vascular development. With congenital anomalies of the cerebral vessels, a change in their course is determined, the presence of pathological tortuosity, branches of small vessels in the pathological area.
- Vasculitis. Vasculitis is characterized by a violation of the differentiation of the wall layers, a change in echogenicity.
The results of vascular ultrasound diagnostics are not used in isolation when making a diagnosis. Their interpretation is carried out taking into account anamnesis, clinical picture and laboratory data. Ultrasound examination is often the primary stage of visualization and requires the addition of MRA results.
Ultrasound remains the optimal diagnostic method in terms of the ratio of information content and cost of the procedure. It has practically no contraindications, is safe and painless, can be used to examine all categories of patients: newborns, pregnant women, the elderly, somatically weakened people. In comparison with MRA, REG or CT sonography has a lower cost, but it does not always allow you to get a complete image of the vessel and determine the factors of patency disorders. The informative value of the study is negatively affected by the presence of an obstacle to ultrasound waves in the form of bone tissue.