China
Africa
Explore chapters and articles related to this topic
Automated Diagnosis and Prediction in Cardiovascular Diseases Using Tomographic Imaging
Published in Ayman El-Baz, Jasjit S. Suri, Big Data in Multimodal Medical Imaging, 2019
Lisa Duff, Charalampos Tsoumpas
In summary, there are multiple approaches to cardiac imaging, and the more suitable depends on the patient’s condition and situation and the availability of the technique. CTA provides anatomical information such as detecting narrowing of the blood vessels. It requires a contrast agent to make the vessels easier to observe and does expose the patient to some radiation. CMR or MRA also record anatomical information but are better suited to soft tissues. They can be optimised by altering the pulse sequence but sometimes still require a contrast agent. Radionuclide imaging is more suitable to functional assessments of body processes such as perfusion or inflammation. Echocardiography uses ultrasound to image the heart, and it is cheap and accessible. The choice of modality depends on the clinical situation and protocols.
Hypertension and Correlation to Cerebrovascular Change: A Brief Overview
Published in Ayman El-Baz, Jasjit S. Suri, Cardiovascular Imaging and Image Analysis, 2018
Heba Kandil, Dawn Sosnin, Ali Mahmoud, Ahmed Shalaby, Ahmed Soliman, Adel Elmaghraby, Jasjit S. Suri, Guruprasad Giridharan, Ayman El-Baz
Computed tomography angiography (CTA) is an imaging technique that uses an intravenously administered iodine-rich contrast agent to capture X-ray images of blood and vasculature. A sample of a CTA image is shown in Figure 16.2. It can be used to assess arterial sizes, evaluate blood flows to diagnose vascular conditions such as stenosis (narrowing of the blood vessel), embolism (blockage), atherosclerosis, etc. Ley et al. used CTA of pulmonary arteries to diagnose patients with chronic thromboembolic pulmonary hypertension [25]. CT perfusion imaging enables evaluation of cerebral blood flow and perfusion. Multi-detector computed tomography (MDCT) utilizes a two-dimensional array of detector elements instead of a linear array of detector elements used in typical and helical CT scanners [26], which allows for high imaging acquisition speed, high spatial resolution, and more coverage of the patient [27]. Flat panel CT (FPCT) offers z-axis imaging in one rotation, which offers high spatial resolution images of entire organ systems (e.g., the cerebrovasculature) [28], [29].
Perfusion Brain Mapping in the Treatment of Acute Stroke
Published in Yu Chen, Babak Kateb, Neurophotonics and Brain Mapping, 2017
Michael J. Alexander, Paula Eboli
Computed tomography angiography (CTA) evaluates cerebral vasculature and aids in diagnosing vessel occlusion due to the presence of thrombus or stenosis, while CTP allows the identification of infarcted and/or ischemic tissue.
Identifying and addressing the limitations of EVAR technology
Published in Expert Review of Medical Devices, 2018
Viony M Belvroy, Ignas B Houben, Santi Trimarchi, Himanshu J Patel, Frans L Moll, Joost A. Van Herwaarden
CTA is more accurate than US in estimating the aortic diameter, the longitudinal distance, such as the neck length of the aneurysm and gives a clear view of the anatomy without possibly influencing the measurements with external pressure. This accuracy is very important for surgical planning, especially regarding the landing zones and graft sizing in EVAR [19]. CTA is superior as imaging modality in work-up for intervention (Figure 2) [18]*. The cardiac cycle influence is estimated to have a profound effect on stent-graft selection and design [20]. This difference between systole and diastole is accounted for using high-resolution electrocardiography-gated (ECG-gated) CTA. This is a dynamic CTA method, which can detect significant changes in the aortic pulsatility, by synchronizing the CT scan and the cardiac cycle [21].