THE ATTEMPT OF THE BLOOD VESSEL CONTRACTIBILITY ESTIMATION ON THE BASIS OF THE COMPUTED TOMOGRAPHY IMAGING 3

Cardiovascular mortality remains a leading health a nd social problem in many countries throughout the world. Its main cause is related to atherosclerosis of cor onary and cerebral vessels with their most severe c onsequences: heart attack and stroke. Therefore, it is obvious that cu rrent preventive measures include early detection o f atherosclerosis process. Multi-detector computed tomography (MDCT) is one of imaging modalities allowing for noninvasi ve detection of atherosclerotic lesion within coronary arteries in subjects with accumulation of risk factors (smok ing, high lipids, hypertension, male gender, family history) or with suspicion of coronary artery disease (CAD). In is very important that the tomographic images are taken in synchroniz ation with cardiac cycle so that, during few heartb eats, an appropriate series of images can be recorded. Commonly, cardiac MDCT is used for visualization of card iac and vessels morphology. Heart function can also be determined, however, this MDCT potential is only rarely applied , as current echocardiographic modalities are sufficient. Functi onal analysis of coronary arteries (flow, reserve) is usually approached by means of invasive procedures. We aimed at finding solution for evaluation of another kin d of functional analysis of coronary arteries, namely vessel’s wall compliance by means of MDCT coronary angiography. Under the proposed procedure, on basis of serial CT images of the vessels over entire cardiac cycles, the internal area of the blood vessel is measured and its change s during various phases of heartbeat (systole, dias tole) are calculated. If the vessel wall has been changed by atherosclero tic plaque, either calcified or non-calcified, then its compliance will be reduced due to its stiffness. Calculation of cor onary artery compliance requires a series of measur ements, which is unreliable and impractical for doing manually. One component of the method described herein involves the images being converted into binary represent ations and the Hough Transform then applied. The overall methodology proposed in this paper assists in the pr eparation of a medical diagnosis.