CT scan of the aorta: emergency and planned
With aortic dissection, hours are counted - CT angiography in minutes shows the detached intima, true and false lumen, length and involvement of branches, which determines emergency surgery. Routinely, the study measures the diameter of the aneurysm (operation for 5–5.5 cm and growth more than 0.5 cm per year), the condition of the valve and aortic root, and after prosthetics or stent grafts, the tightness and position of the prosthesis. If necessary, expands to panorathography with the abdominal aorta. Creatinine and no allergy to iodine are required.
Indications
- aneurysm and aortic dissection, chest and back pain with suspected vascular accident;
- coronary heart disease - non-invasive assessment of coronary arteries, calcium index;
- pulmonary embolism (PE) with shortness of breath and chest pain;
- stenosis of the carotid and cerebral arteries, cerebral aneurysms, stroke;
- obliterating atherosclerosis and intermittent claudication - arteries of the legs before surgery;
- planning of stenting, bypass surgery, aortic endoprosthetics, monitoring after them.
What is MSCT
Multislice computed tomography is a layer-by-layer X-ray study in which detectors receive dozens of sections up to 0.5–1 mm thick in one revolution of the tube, and a computer builds a three-dimensional image of the organ. MSCT is performed in 5-15 minutes, accurately shows bones, lungs, stones, hemorrhages, tumors and vessels (with contrast), and is often the method of choice for trauma and acute conditions when MRI is too long or contraindicated.
Preparation and contrast
Non-contrast MSCT does not require preparation. Before a study with intravenous contrast, a test for creatinine (kidney function) and the absence of an allergy to iodine are required; 4–6 hours without eating; When taking metformin, agree on a break with your doctor. Contrast (Unigexol) is administered using an automatic injector; a feeling of warmth for 1–2 minutes is normal. To examine the abdominal and pelvic organs, oral contrast is used, which is drunk 30–60 minutes before the scan. Remove metal objects from the examination area. The radiologist’s conclusion is completed within 1–2 hours, the images are issued on film and disk.
Radiation exposure and safety
Modern devices use low-dose protocols; the dose for one study is comparable to several months of natural background and does not accumulate dangerously when prescribed appropriately. MSCT is not performed on pregnant women (except for vital indications); for children - according to strict indications with a minimum dose. Iodine contrast is contraindicated in severe renal failure, iodine allergy and uncontrolled hyperthyroidism. Pacemaker and metal implants are not a contraindication, unlike MRI.
