Magnetic Resonance Imaging and Ultrasound Scans - Coursework Example

PREGNANCY RISKS & SCANNING METHODS: A CRITICAL REVIEW OF COMPUTED TOMOGRAPHY, MAGNETIC RESONANCE IMAGING & ULTRASOUND SCANS Contents Contents 2 Introduction 3 Computed Tomography (CT) 3 Magnetic Resonance Imagining (MRI) 5 Ultrasound 7 Conclusion & Risk Reduction 9 Bibliography 11 Introduction There are some modern methods and approaches for examining foetuses as they develop within the gestation period of a patient. These methods include Computed Tomography (CT), Magnetic Resonance Imaging (MRI) and Ultrasound (US) and they are all utilised to examine and evaluate pregnant women’s statuses and the impacts of their pregnancies. The purpose of this paper is to examine the possible biological risks and hazards that are associated with these three methods when imaging a pregnant patient. This will be done by the examination of the scientific principles and modalities that will aid comparisons and contrasts that will show the main risks. In the process recommendations of how to reduce and ameliorate these risks are critiqued and examined Computed Tomography (CT) A computed tomography (CT) scan utilises x-rays to provide detailed pictures of structured inside the body of pregnant women (WebMD, 2013). The process is done by getting a pregnant woman to lie on a table that is attached to a CT scanner which is round with an inner-hollow (Romans, 2010; Prokop & Galanski, 2013). The scanner sends x-rays throughout the body and the pictures are studied appropriately (Kalender, 2011). The rotation comes with pictures that are captured and saved on a computer that can be retrieved or printed. CT Scans present more detailed and thorough pictures and images of the area of interest in a medical study or examination (Patient UK, 2014). The system uses conventional radiology and as such, it opens a patient up to the risks of other x-ray systems and processes (DeMaio, 2010; Buzug, 2008). CT Scans opens up a pregnant woman to various risks of radiation during the process, however, the amount of radiation that a pregnant woman will be exposed to varies. Some authorities identify that a patient taking a pregnancy related scan will be exposed to 6.6mSv of radiation which is approximately three years’ worth of background radiation (NHS Choices, 2013). This is obviously very high and could expose a pregnant woman and a foetus to some dangerous levels of radiation. There are various levels of risks that foetuses are directly exposed to during CT scans. The level is examined in a study by Marx et al on the Uterine Radiation Dose (MRAD). The head is exposed to under 50 MRAD, the Thorax is exposed to 10-590 MRADs, the Abdomen, 2800 – 4,600 MRADs whilst the Pelvis is exposed to 1,940-5,000 MRADs (Marx, Lockberger, Walls, & Adams, 2013). However, the inherent benefit is that it is quick and accurate and it is often the best way to check a patient in lieu of an all-out surgery which may take time and effort that is detrimental (NHS Choices, 2013). Thus, it allows medical professionals to get enough information and background to a given problem in order to provide important insights. Due to the nature of CT Scans, it is not recommended for pregnant women as it is likely to harm the baby in the womb and increase the probability of giving birth to a child with serious deformities that would last a lifetime. However, in very serious cases where the pregnant woman needs to take such a scan, it might be the only option that could potentially deduce a life-threatening situation, it could be carried out (Davies, Wathen, & Gleeson, 2011). The position above is very general because it can be inferred from logic and provides important ideas. Authorities in medical practice and pregnancy care however assert that clinicians are not well informed of the facts related to the use of diagnostic radiological studies in pregnancy (Augustin, 2014). The lack of understanding also aids anxiety and this might also be seen to be a cause of viewing CT scan examinations as an issue related to the termination of pregnancies (Augustin, 2014). The move from the traditional CT systems and structures has led to the creation of low-dose CT scan protocols that can be used for the detection of renal calculi during pregnancy (Preminger, Badlani, & Kavoussi, 2013). This provides a mean exposure of 705.5 MRADs which is within a range of 244-1372MRADs. This makes it less likely to cause harm to a pregnant mother. Thus, the Research Ethics Board has approved a study whereby the authors conclude that the use of very low-dose CT scans can help in studying women who have reported flank pains that have not been sufficiently detected by ultrasound scans (Preminger, Badlani, & Kavoussi, 2013). This leads to better decision-making and the analysis of a situation. Therefore, there is the need for the balance of the circumstances in order to achieve best results and findings. Magnetic Resonance Imagining (MRI) MRI utilizes radiology to investigate the anatomy and physiology by examining radio waves of the human body in order to identify important trends and formations within the bones and tissues of a pregnant woman (Powell, Worthington, & Symonds, 2012). There are certain classes of patients who are at risks of exposure to MRI levels. This includes the extremely low frequency and magnetic fields this is because the patients are susceptible to the heating and their thermoregulation might be seen to be at risk when MRI is used (Sundgren & Leander, 2011; Edlow, Caplan, OBrien, & Tibbles, 2013). Early studies by the British Nuclear Regulatory Policy Bureau in 1983 recommended that women in their first three months of gestation should be excluded from MRI scans (Shellock, 2002). In 1989, another study by the US Food & Drugs Administration (FDA) indicated that the safety of MRI in the imagining of foetuses and infants had not been established (Shellock, 2002). Therefore, many authorities identified that there were similarities between MRI and other non-ionizing forms of diagnostic images like CT, hence it should not be used in pregnant women. However, Powell et al go on to state that there is no good evidence that human embryos are sensitive to magnetic fields encountered in MRI scans (2012 p15). Therefore, it is a prudential ethical practice to exclude women who are in the first three months of their pregnancy. Therefore, MRI is considered where the only real alternative to the scan is an x-ray oriented scan like CT (Mullins, Semins, Hymans, Bohlman, & Matlaga, 2012). Many authorities assert that there is no evidence that shows that MRI is harmful to pregnant patients or their foetuses (Bushong & Clarke, 2012). However, there is a general consensus that the heat of MRI usage in pregnancy is a direct threat to the health of a pregnant woman who undergoes the test (Shields & Candib, 2010). This is because the heat causes the woman to suffer some kind of discomfort and it is logical to assert that it could cause various levels of medical issues and problems. Some authorities like Bushong and Clarke (2012) argue that the use of these MRI systems is the same as exposing a pregnant woman to a steam or any other hot environment like a hot tub. There have been clinical evidence that shows that the study of pregnant pigs culminated in the changes in the temperature of amniotic fluids, foetal brain and foetal abdomen when MRI was used (Nyberg, 2003). This was the result of over 10 years of studies and evaluation of the pregnancies and the evaluation of the mammalian foetuses of the study. However, unlike other indications in the use of CT, these symptoms do not cause any biological deformities and challenges that are significant enough (Han, Gziri, Calsteren, & Amant, 2013). Hence, there is a general view that MRI scans are somewhat safe. “According to the Safety Committee of the Society for Magnetic Resonance Imaging, magnetic resonance procedures are indicated for use in pregnant women if other non-ionizing forms of diagnostic imaging are inadequate, or if the examination provides important information that would otherwise require exposure to ionizing radiation (ie, x-ray computed tomography)” (Nyberg, 2003, p. 989). Therefore, there is the view that MRI is a generally safer option when compared to CT. This implies that in cases where MRI and CT can achieve the same functions in a pregnant woman, there is the need for MRI to be utilised ahead of CT. Ultrasound Over time, different measures like ultrasound that were developed ionizing radiation were developed and this provides better and more improved systems and processes of doing thing in order to view the foetuses and identify trends and processes going on with the foetus (Levy, et al., 2012; Brandao, Mottola, Gratton, & Maloni, 2011). Prenatal ultrasound scan utilises high-frequency sound waves that are transmitted through the abdomen through a device known as a transducer which looks into the abdomen of a pregnant woman (WebMD, 2014). The Ultrasound technology is different from the other methods of checking and evaluating foetuses because it involves the examination of the waves that bounces off the baby in the womb (BabyCentre, 2014). This process involves the utilisation of important techniques to accurately predict important elements and features of the baby and his or her features that can be documented in order to provide important patterns about the formation and the features of the baby (Kurjak, 1994). The echoes and imaging indicates that the amniotic fluids appear as black on the computer screen whilst the sonographer interprets and provides meanings of the trends and processes (Wladimiroff & Eik-Nes, 2009). Most authorities identify that ultrasound scans of foetuses have little or no connection to any known sicknesses and deformities in children (Rosene-Montella, 2009). However, some research works conducted show a possible connection between some deformities and defects in the development of babies with ultrasound scans. In her critical study conducted over 8 years ago, Caroline Rodgers drew several links and connections between ultrasound scans and many issues and deformities. She asserts that “...although proponents point out that ultrasound has been used in obstetrics for 50 years and early studies indicated it was safe for both mother and child, enough research has implicated it in neuro-developmental disorders to warrant serious attention.” (Rodgers, 2006, p. 235). This indicates that there are various neurotic issues and matters that could potentially be connected or linked to ultrasound scans. This includes development in the brain that gives rise to major problems like left-handedness in boys and speech delays (Rodgers, 2006). However, most of these risks are identified to be highly remote and there is limited scientific basis to prove this in the real and absolute sense. Like MRI, ultrasound scans come with major problems and issues that relate to the increase in temperature (Bluth, 2000). This is because the whole process includes important issues that utilises energy. And as more energy is generated and used, the temperature of the regions studies increases and this could have an impact on the formation and growth of the foetuses (Berghella, 2007). Conclusion & Risk Reduction From the discussions above, it is apparent that CT provides a system of scanning and reviewing important trends and features in the body of a pregnant woman. This provides more thorough and deep information about the patient. This includes showing information about hidden medical issues that cannot be found. In spite of this, CT comes with a high level of radiation. Therefore, it seem the only way around this is to utilise it if and only if it is important in helping to deduce and deal with a given situation. This is because the radiations make it an undesirable option and it has to be used when it is needed. On the other hand, MRI uses important techniques and systems that increases the temperature of the foetus. Though the evidence is not established, it appears that MRI must also be used when needed. However, a practitioner could be more liberal in utilising MRI than CT because it does not have such fatal and obviously dangerous radiation levels as CT. Thus, MRI could be used in non-lethal situations. From all indications, US is not dangerous in any way or form. Therefore Ultrasound Scan is the safest and the least risky system of checking pregnant women. It is therefore the most recommended system for checking things in pregnant women. MRI is a middle-class system and procedure with less risks. However, CT poses the most risks to pregnant women who go through medical scans. This is because it uses a technology that does not support radiation. This makes it ideal for personal uses and uses that are not mandatory or induced by serious medical conditions. Therefore, US could be used by parents who want to find out about the gender or features of their babies for the pleasure of it. The risks related to MRI and US vary slightly. This is because MRI’s risks can be inferred with a high level of logic. However, the direct biological risks are not proven. On the other hand, US’s risks are very remote and up till now, they are just circumstantial and have not been established very accurately. Bibliography Augustin, G. (2014). Acute Abdomen During Pregnancy. London: Springer. BabyCentre. (2014, April 4). Pregnancy ultrasound scans: an overview. Retrieved from Baby Centre UK: http://www.babycentre.co.uk/a329/pregnancy-ultrasound-scans-an-overview Berghella, V. (2007). Maternal-Fetal Evidence-Based Guidelines. New York: CRC Press. Bluth, E. I. (2000). Ultrasound: A Practical Approach to Clinical Problems. London: Thieme. Brandao, K. L., Mottola, P. L., Gratton, R., & Maloni, J. (2011). Bone Status in Activity-Restricted Pregnant Women Assessed Using Calcaneal Quantitative Ultrasound. Biological Research on Nursing. Bushong, S. C., & Clarke, G. (2012). Magnetic Resonance Imaging: Physical and Biological Principles. London: Elsevier Health Sciences. Buzug, T. M. (2008). Computed Tomography: From Photon Statistics to Modern Cone-Beam CT. London: Springer. Davies, H. E., Wathen, C. G., & Gleeson, F. V. (2011). Risk of Exposure to Radiology Imaging and How to Minimise them. Clinical Review, 581-589. DeMaio, D. N. (2010). Mosby’s Exam Review for Computed Tomography. London: Wolters Kluwer Publishing. Edlow, J. A., Caplan, L. R., OBrien, K., & Tibbles, C. D. (2013). Diagnosis of acute neurological emergencies in pregnant and post-partum women. The LANCET Neurology, 175-185. Han, S. N., Gziri, M. M., Calsteren, K. V., & Amant, K. (2013). Cervical cancer in pregnant women: treat, wait or interrupt? Assessment of current clinical guidelines, innovations and controversies. Therapeutic Advances in Medical Oncology, 211-219. Kalender, W. A. (2011). Computed Tomography: Fundamentals, System Technology, Image Quality. 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C., & Leander, P. (2011). Is administration of gadolinium-based contrast media to pregnant women and small children justified? Journal of Magnetic Resonance Imaging, 750-757. WebMD. (2013, November 9). Computed Tomography (CT) Scan of the Body. Retrieved from WebMD: http://www.webmd.com/a-to-z-guides/computed-tomography-ct-scan-of-the-body WebMD. (2014). Prenatal Ultrasound . Retrieved from WebMD: http://www.webmd.com/baby/ultrasound Wladimiroff, J. W., & Eik-Nes, S. (2009). Ultrasound in Obstetrics and Gynaecology. London: Elsevier Health. Read More