Computerized tomography: coronary angiography and cardiac imaging

Patients presenting with chronic and acute chest pain constitute a common and important diagnostic challenge. This has increased interest in using computerized tomography for non-invasive visualization of coronary artery disease in patients presenting with acute chest pain to the emergency department, particularly the subset of patients who are suspected of having an acute coronary syndrome, but without typical electrocardiographic changes and with normal troponin levels at presentation. As a result of rapid developments in coronary computerized tomography angiography technology, high diagnostic accuracies for excluding coronary artery disease can be obtained. It has been shown that these patients can be discharged safely. The accuracy for detecting a significant coronary artery stenosis is also high, but the presence of coronary artery atherosclerosis or stenosis does not imply necessarily that the cause of the chest pain is related to coronary artery disease. Moreover, non-invasive detection of coronary artery disease by computerized tomography has been shown to be related with an increased use of subsequent invasive coronary angiography and revascularization, and further studies are needed to define which patients benefit from invasive evaluation following coronary computerized tomography angiography. Conversely, implementation of coronary computerized tomography angiography can significantly reduce the length of hospital stay, with a significant cost reduction. Additionally, computerized tomography is an excellent modality in patients whose symptoms suggest other causes of acute chest pain such as aortic aneurysm, aortic dissection, or pulmonary embolism. Furthermore, acquisition of the coronary arteries, thoracic aorta, and pulmonary arteries in a single computerized tomography examination is feasible, allowing ‘triple rule-out’ (exclusion of aortic dissection, pulmonary embolism, and coronary artery disease). Finally, other applications, such as evaluation of coronary artery plaque composition, myocardial function and perfusion, and non-invasive assessment of fractional flow reserve from coronary computerized tomography angiography, are currently being developed and may also become valuable in the setting of chronic and acute chest pain in the future.

The Supraclavicular Artery Perforator Flap: A Comparative Study of Imaging Techniques Used in Preoperative Mapping

Background The supraclavicular artery flap is an excellent flap for head and neck reconstruction. The aim of this study is to assess imaging techniques to define the precise vascular boundaries of this flap. Methods Six imaging techniques were used for supraclavicular artery mapping in 65 cases; handheld Doppler, triplex ultrasound, computed tomography angiography, magnetic resonance angiography, digital subtraction angiography, and indocyanine green angiography. We checked the site of the perforators, the course of a supraclavicular artery, and anatomical mapping of the supraclavicular artery. Results Handheld Doppler identified perforators' sites in 80% of the cases but showed no results for the course of the vessel. Triplex ultrasound identified the site of perforators in 52.9%, and partial mapping of the course of a supraclavicular artery in 64.7% of the cases. Computerized tomography angiography showed the site of perforators in 60%, and the course of supraclavicular artery completely in 45%, and partially in an additional 30%of the cases examined. Magnetic resonance angiography showed negative results for all parameters. Digital subtraction angiography showed the partial course of a supraclavicular artery in 62.5%, but showed no perforators. Indocyanine green angiography showed the site of perforators in 60% and a partial course of supraclavicular artery distal to perforators in 60%.Anatomical mapping of the vessel was possible with computerized tomography angiogram completely in 45%, and partially in 30%, and was also possible with indocyanine green angiography partially in 60%. Conclusion Computerized tomography angiography showed best results in the mapping of the supraclavicular artery, but with an inability to define the perforator perfusion territories, and also with risks of irradiation, while indocyanine green angiography is a good alternative as it could precisely map the superficial course of the artery and angiosomes, with no radiation exposure.