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Multisensor Data Inversion and Fusion Based on Shared Image Structure
Published in Rick S. Blum, Zheng Liu, Multi-Sensor Image Fusion and Its Applications, 2018
Robert A. Weisenseel, William C. Karl, Raymond C. Chan
An example application for which information fusion plays an important role is the characterization of atherosclerotic plaques from multimodality vascular imagery. This is an area of active biomedical research interest since high-risk plaques are vulnerable to rupture, resulting in heart attacks or strokes which are the major causes of death and morbidity in the U.S. No single modality can currently provide unambiguous assessment of such vulnerable plaques. As a result, many research groups have turned to multimodality sensing for plaque imaging both ex vivo and in vivo as a means of interrogating different physicochemical properties of atherosclerotic lesions, and there is interest in evaluating the relative strengths of new vascular imaging techniques that are available. Information fusion allows for complementary measurements from each sensor to be combined, integrating the strengths of each modality to improve our ability to characterize the properties of vulnerable plaques and ultimately to improve clinical diagnosis and treatment.
Cardiovascular Health Informatics Computing Powered by Unobtrusive Sensing Computing, Medical Image Computing, and Information Fusion Analysis
Published in Ayman El-Baz, Jasjit S. Suri, Cardiovascular Imaging and Image Analysis, 2018
Chengjin Yu, Xiuquan Du, Yanping Zhang, Heye Zhang
Developing high resolution biomedical imaging is crucial for early prevention of CVD. Atherosclerosis is the main cause of acute cardiovascular disease [60]. The development of atherosclerosis will lead to unstable atherosclerotic plaques or vulnerable plaque, which is characterized as active inflammation, a thin fibrous cap with a large lipid core, erosion or fissure of the plaque surface, intra-plaque hemorrhage, and superficial calcified nodules [60][61]. Vulnerable plaque will narrow blood vessels or even occlude the vessel, resulting in the block of blood flow to vital organs, such as the heart and the brain. If the treatment of atherosclerosis is delayed, subsequently the rupture of vulnerable plaque will cause acute coronary death or stroke [60]. In addition, other kinds of cardiac diseases, such as myocarditis, electrophysiological disorders, valvular heart disease, and other cardiomyopathies (hypertrophic, dilated, or restrictive) are often related to vulnerable myocardium, and vulnerable plaques, which have a high likelihood of thrombotic complications and rapid progression, and so should be diagnosed and treated as early as possible [25][10].
The Mechanical Changes Associated with Aging in the Cardiovascular System
Published in Michel R. Labrosse, Cardiovascular Mechanics, 2018
Arteriosclerosis predominantly affects the medial layer of an artery, while, as discussed in more detail in Chapter 7, atherosclerosis is a focal disease of the intimal layer and manifests itself by lesions that accumulate lipids, inflammatory cells, and fibrous tissue (Figure 11.3a vs. b and c vs. d). The lesions develop to form calcified plaque, which obstructs blood flow and may result in clinically significant ischemia. However, the most dangerous situation occurs when the so-called vulnerable plaque ruptures. The mechanical failure of the thin fibrous cap of the plaque results in the formation of thrombus, which may suddenly block an artery. Myocardial infarction frequently arises from this mechanism.
Computational fluid dynamic simulation of two-fluid non-Newtonian nanohemodynamics through a diseased artery with a stenosis and aneurysm
Published in Computer Methods in Biomechanics and Biomedical Engineering, 2020
Ankita Dubey, B. Vasu, O. Anwar Bég, Rama S. R. Gorla, Ali Kadir
Interesting examples of the deployment of nanofluids in medicine include blood purification systems (Anwar Bég et al. 2014), smart bio-nano-polymer coatings for medical devices (Uddin et al. 2018), nano-drug delivery (pharmacological systems) in cardiovascular treatment (da Costa Santos 2015; Rizvi and Saleh 2018), biodegradable nanoliquids for cerebral pharmaco-dynamics (Akbar et al. 2017), membrane oxygenator bioreactors (Anwar Bég 2018), orthopedic lubrication with nano-films (superlubricated poly (3‐sulfopropyl methacrylate potassium salt)‐grafted mesoporous silica nanoparticles suspended in starch base liquids) (Yan et al. 2019), pulsed laser ablation (PLA) ultra-pure silicon nanofluid fabrication for cancer therapy (Raj Sha et al. 2018), smart biomimetic electro-osmotic nanofluid pumps in ocular diagnosis (Tripathi et al. 2017), cryopreservation, bone reinforcement via super-paramagnetic nanofluids etc. In hemodynamic therapies, the base liquid is clearly blood and can be doped with a variety of nanoparticles, including gold. To prevent in-stent restenosis and to improve the performance of current stents, different nanomaterial coatings, and controlled-release nano-carriers are used (Karimi et al. 2016). Nano-carriers have the potential for delivery of imaging and diagnostic agents to precisely targeted destinations. Current therapies focus on decreasing the burden of atherosclerotic plaque and stabilizing vulnerable plaques defined as those plaques, which tend to rupture and cause thrombosis (Rhee and Wu 2013). A new type of stent has been designed in recent years and is known as the drug-eluting stent (DES), which reduces the risk of in-stent thrombosis and restenosis caused by bare-metal stents. Different classes with a wide range of drugs have been tested with DES to prevent smooth muscle cell (SMC) growth and proliferation, anti-cancer, and anti-inflammatory agents. Giljohann et al. (2010), and Kumar et al. (2007), investigated the effect of gold nanoparticles suspension in blood. Ali et al. (2018) presented a comprehensive computational model for studied unsteady heat and mass transfer in nanoparticle doped streaming blood flow via a tapered stenotic artery using the Buongiorno model.
Effects of magnetohydrodynamic unsteady fluid flow over a narrow channel in the axial and radial directions
Published in International Journal of Ambient Energy, 2022
S. Ganesh, V.W.J. Anand, P. Chandrasekar, M. Anish
One of the reasons for major causes of deaths throughout the world today is due to the diseases related to heart. These occur due to sudden deficiency of oxygen or less supply of blood to the heart. This may occur because of a constriction or obstruction in the blood supply to that part and due to the deposit of very fatty substances of cholesterol, cellular waste product, calcium, etc. This they call it as stenosis. Rupture of plaque surface along with thrombosis superimposed and luminal blockage is considered as reason for heart attacks. The risk of plaque rupture depends on plaque type (composition) rather than plaque size (volume) because only plaques rich in soft extracellular lipids are vulnerable (rupture-prone). In conditions like this, coronary arteries can be occluded with fatty deposits which causes vulnerable plaque (VP) that may generally trigger rapid thrombosis upon rupture which results in heart attack. The important objective of this paper is to find the ways of reducing severe effects of hemodynamic which leads to VPs ruptured by the development of a mathematical model based on the principles of Biomagnetic Fluid Dynamics. One question that could be raised is whether a magnetic field could really influence the flow at the stenotic region as blood contains iron. A biofluid which is generally a Newtonian, homogeneous, incompressible and electrically conducting fluid where the flow is considered laminar. Blood is considered as one of the most characteristic biofluids, which exhibits electrical conductivity. Flow which are biofluid in nature are generally under the influence of an applied magnetic field which are always consistent with magnetohydrodynamic (MHD) and ferrohydrodynamic (FHD) principles (Akbarzadeh 2016). Pulsatile magnetohydrodynamic blood flows through porous blood vessels using a third-grade non-Newtonian fluids model Computer Methods and Programs in Biomedicine. Hayat et al. (2017) studied entropy generation analysis for peristaltic flow of nanoparticles in a rotating frame. Chakravarty and Mandal (2000) discussed two-dimensional blood flow through tapered arteries under stenotic conditions. When the magnetic field which is uniform and steady is applied, MHD principles cannot be ignored either locally or globally and this plays a very important role in the flow field formation. This model beyond doubt proved to be very useful in knowing the magnetic field influence in the study of MHD physical problems by Akbarzadeh (2016), Hayat et al. (2017) and Chakravarty and Mandal (2000).