1. Explain what ultrasound contrast agents (USCA) are.
2- Use Chicago Curtin style 16th edition as references style, I uploads on PDF file to help you in references style.
3- You are required to answer the questions and you are also expected to include illustrations (diagrams, pictures, etc) with references for picture and diagram
4- At least 5 journals articles of 10 references published in the last 5 years.
5- Avoid plagiarism.
6- Write text citation with page number for each paragraph or new information.
7- Add table of contents.
TABLE OF CONTENTS
According to the Work Health and Safety Act and Regulations 2011, Ultrasound Contrast Agents (USCAs) has the responsibility to manage threats that transpire at USCA in terms identifying foreseeable threats, reviewing the threats, monitoring and managing the threats. Based on studies, contrast agents can be employed safely on the sick in offering optimal imaging. This essay sets out to discuss the risk factor relating to USCAs and their general safety.
2. RISK ASSOCIATED WITH USCAs
USCAs are synthesized from different kinds of biocolloid particles such as gas-liquid emulsions (Microbubbles), liquid-liquid emulsions (nanodrops), and liposomes (Borden et al. 2011) (Figure 1). Microbubbles are vascular contrast substances that used in ultrasound; air is stabilized in a membrane like small soap bubbles that provides marked reflections at a high frequency and operates effectively in ultrasound frequency of 2-10 Hz (Seidel & Meairs. 2009).
Microbubble can contribute to leakage of microvascular, rupture of the capillary, inflammation among others. This is associated with high blood pressure in capillary leading to bleeding and poor function of the nephron (Wheatley & Cochran 2013). Rupture of the capillary may be short-term as well as reversible, however in about 50 percent of affected nephron can cause permanent inability to function. Thus, microbubble can potentially contribute damage to human body, particularly in high ultrasound frequencies, increased imaging period and higher micro-bubble concentration (Paradossi et al. 2010). Micro-bubbles are formed by proteins and surfactant. The average size range between 33.6 to 51.1 μm, and cv values of less than 10 percent. The formation characteristics are compared with droplet development. In addition, formation based on natural conversion caused via surface tension (Seidel & Meairs. 2009).
There are marked improvements in echocardiography diostic capabilities that have resulted from the introduction of the ultrasound contrast agents, such as; Definity®, BY 963, CARDIOsphere®, EchoGen, and Albunex among others. During the preclinical development stage there were no serious adverse effects which were recorded. This led to the ultrasound being considered safe, but recently there have been some fatal cases that have been reported .This has led to the addition on the use of several contra indications in the use of ultrasound agents. It is clear there has been established a strong relationship between the cases that are non-fatal the sonovue administration. Therefore, the adverse risk associated with the use of these agents should be carefully judged putting into consideration that the adverse effects prevalence on the other contrast media used in cardiology (Dijkmans et al. 2005).
USCAs such as; Definity®, BY 963, CARDIOsphere®, EchoGen, and Albunex are the main causes of certain issues, which have also enhanced the safety alert. The case in point is related to patients diagnosed with heart disease, diabetes and myocardial infraction (Mulvana et al. 2010). Evidence based practices indicate that these patients were associated with life threatening conditions that required some intervention before an ultrasound contrast agent. By and large, these patients suffered from a heart attack in a span of 30 minutes after UCA was administered (Hoskins et al. 2010). Nonetheless, death was caused by unrelated scenarios to contrast delivery by respective medical experts.
USCAs can enhance image quality by minimizing reflectivity of undesired regions or even maximizing backscattered echoes form preferred sections (Figure 2). In the former technique, agents are taken orally and latter approach the contrast agent is vascular introduced (Figure 3).
Figure 2: An enhanced imaged after use of USCA (Krix et al. 2011)
Figure 3: An image showing where the USCA should be injected depending on the targeted area of drug delivery (Correas et al., 2008).
USCAs are a composition of stabilized shell that summarizes a gas bubble. Once these agents are introduced in the body they help to increase the scattering of the acoustic. This scattering moment is passes into tissue mostly from the vasculature. There is a lot of potential from the microbubbles that helps them act like acoustic captivation activity. This makes it important to consider the safety on their use from an acoustic perspective. (Kusnetzky, et al. 2008 ). To determine the performance of ultrasound contrast agents, echocardiogram imaging has been contrasted with images from patients that hardly require services rendered by contrast agents. What has been established is the fact that both images are ok. In this regard, best possible echocardiography images make it necessary for physicians to identify and remedy deadly coronary heart complication (Kusnetzky, et al. 2008 ). This capacity is what makes ultrasound contrast agents pertinent. However, to determine this benefit, scholars looked at long-term survival rate of patients that got services from contrast agents, and were able to note identical death rates between the two clusters. It is clear that the MI (Mechanical Index) display in the US has been made mandatory for all practicing ultrasound contrast agent, such as; Definity®, BY 963, CARDIOsphere®, EchoGen, and Albunex among others to act as a safety measure in the estimation processes of the tissue effects of exposure in ultrasound to be prepared. This move also has some reflection on the mechanical effects that ultrasound has on the contrast bubble. As a result, the process has shown some usefulness in developing a machine setting for ultrasound contrast agents (Hoskins et al. 2010). In 1997 FDA (Food and Drug Administration) has enhanced a black box alarm that would then be embedded on ultrasound contrast agents USCAs, perflutren monographs. This prompted various healthcare systems to follow suit by generating a security awareness including analogous considerations. This prevented the use of USCA would include terminal cardiac signs, terminal myocardial infarction as well as medically unstable heart malfunction Borden, et al. 2011).
From the research, it is therefore apparent that the use of USCA is safe to be used apart from the few discussed safety case that are not so frequent. The implementation of USCAs into the clinical practice will lead into a diagnostic power of Echocardiography. Contrast agents have also proved to be nontoxic and the only problem in existence is the development of numerous methods to help in the imaging process of agents such as; Definity®, BY 963, CARDIOsphere®, EchoGen, and Albunex. However, the challenge is to come up with better agents that can have greater stability. Although there are a few cases of safety issue concerning ultrasound contrast agents, there are no effects that are adverse to the human beings that has been reported to date. It can therefore be concluded that even though normal ultrasound method has noninvasive feature as well as easy modality the use of these ultrasound contrast agents can result in better results in a medical environment.
Borden, M., S. Qin, and K. Ferrara. 2011. “Ultrasound Contrast Agents”. Molecular Imaging: Principles and Practice. Chapter 12: 425-444. http://www.pmph-usa.com/assets/media/9781607950059/Chapter28_FINAL_NOV_2_2011.pdf (access date 25 October 2013).
Correas, Jean-Michel, Lori Bridal, Amélie Lesavre, Arnaud Méjean, Michel Claudon, and Olivier Hélénon. 2008. “Ultrasound contrast agents: properties, principles of action, tolerance, and artifacts.” European radiology. 11(8): 1316-1328.
Dijkmans PA, Visser CA, Kamp O (2005) Adverse reactions to ultrasound contrast agents: is the risk worth the benefit? Eur J Echocardiogr 6:363–366.
Hoskins, Peter, Kevin Martin, and Abigail Thrush. 2010. “Diagnostic ultrasound: physics and equipment”. Cambridge, UK; New York: Cambridge University Press.
Krix, Martin, Christian Plathow, Fabian Kiessling, Felix Herth, Andreas Karcher, Marco Essig, Harry Schmitteckert, Hans-Ulrich Kauczor, and Stefan Delorme. 2011. “Quantification of perfusion of liver tissue and metastases using a multivessel model for replenishment kinetics of ultrasound contrast agents.” Ultrasound in medicine & biology. 30(10): 1355-1363.
Kusnetzky L.L., Khalid A., Khumri T.M., Moe T.G., Jones P.G., Main M.L.(2008). Acute mortality in hospitalized patients undergoing echocardiography with and without an ultrasound contrast agent: results in 18,671 consecutive studies. J Am Coll Cardiol. 51 2008:1704-1706.
Mulvana H, E Stride, JV Hajnal, and RJ Eckersley. 2010. “Temperature dependent behavior of ultrasound contrast agents”. Ultrasound in Medicine & Biology. 36 (6): 925-34.
Paradossi, Gaio, Paolo Pellegretti, and Andrea Trucco. 2010. Ultrasound contrast agents: targeting and processing methods for theranostics. Dordrecht: Springer Verlag.
Seidel, Günter, and Stephen Meairs. 2009. “Ultrasound Contrast Agents in Ischemic Stroke”. Cerebrovascular Diseases. 27 (Supplement): 25-39.
Wheatley M.A., and Cochran M. 2013. “Ultrasound contrast agents”. Journal of Drug Delivery Science and Technology. 23 (1): 57-72.