الفهرس | Only 14 pages are availabe for public view |
Abstract Coronary artery disease (CAD) is the leading cause of death and disability worldwide, and its prevalence is expected to increase in the coming years. Although catheter angiography remains the gold standard for coronary lumen evaluation. It is an expensive examination, accompanied by the risk of major complications . Therefore, a non-invasive test for the assessment of the coronary arteries is highly desirable. Coronary CT angiography has emerged as an alternative to conventional coronary angiography with high spatial resolution , sensitivity and specificity . Noninvasive coronary angiography by MDCT has shown a high degree of accuracy for the detection of significantly obstructive coronary artery lesions in the arteries where the degree of obstruction of lesions can be assessed. It is also able to give information on the arterial wall itself and on the extent and components of atherosclerotic plaques . A milestone in the development of CT technology was the advent of dual-source CT, which has been described in many articles since its introduction in 2005. Dual-source computed tomography (DSCT) has a considerable impact in the diagnosis of the coronary artery disease. It has a faster imaging technique with a temporal resolution of 83 milliseconds compared to 165 milliseconds of 64-slice single-source multidetector CT. UAdvantages of DSCTA: UIn comparison with CCA, DSCTA has several advantagesU. High spatial resolution of DSCT can help to display the coronary vessel wall, especially to identify the plaque components, such as how much calcified and non calcified plaque are present . Higher temporal resolution has been shown to improve the image quality and thus leads to a broader clinical application. The high negative predictive value suggests an important role of multi-detector coronary CTA for reliably excluding CAD. In addition, DSCT offers the possibility for simultaneous data acquisition with different X-ray energies. As tissues interact differently with the two different X-ray energies, this technology can improve tissue differentiation. In cardiac imaging, it has the potential to ‘remove’ calcification, thus permitting a clearer view of the lumen. In conclusion, our study show that dual source CT coronary angiography is a reliable technique to detect coronary stenosis in patients presenting with chest pain ,especially with arrhythmia or high degree of calcification. It represents a significant advance for coronary CT angiography. It has made CTA more robust and provided reliable assessment of stenosis & vessel wall irregularities. |