Abstract
The field of medicine has gone through an immense transformation over the past years to the betterment of the field. In the past couple decades, there have been significant improvements in the patients imaging. There have been some imaging modalities that have been practiced in the medical sectors to help provide the body structures where standard prescriptive methods have proved ineffective. In the recent years, magnetic resonance imaging has been one of the fundamental modalities used in the imaging in the clinical medicine. There are several benefits and structural advantage that it exhibits over other imaging modalities. Among the benefits and competitive advantage it offers to the field is flexibility regarding technicality. It is also important to underline certain facts that surround imaging. Several hazards can be ignited by the imaging processes such as ionization radiation (Fiebach et al. 2004). However, MRI is considered to be free of the said hazards. It has undergone high-paced development in the recent years to offer a broad range of clinical applicability.
Several new ideas have emerged that provide greater potential regarding performance and efficiency in supporting clinical applications. The technique can be credited to the growing benefits of physical science in nurturing technological ideas that help solve various medical problems in clinical applications. As a leading clinical medicine technology, MRI has become indispensable in the modern diagnostic application by offering robust solutions that cannot be provided by other modalities (Fiebach et al. 2004). This paper attempts to uncover the great metamorphosis that patient imaging has undergone from the use of CT and the emergence of MRI diffusion up to the levels it has reached today. It also unearths the technical capabilities of MRI in comparison to the old techniques and what makes it the most appropriate form of imaging for stroke patients today.
Introduction
The development of magnetic resonance imaging has gone through series of developments since the 1940s.In the early times of 20th century; researchers embarked on a problem-solving endeavor to help find a lasting remedy to the existing problems that were experienced by physicians in handling patients that needed imaging to determine their levels of medical attention (Fiebach et al. 2004). With the first development steps coming from the new results by nuclear magnetic resonance often called NMR. The exploration of NMR was thus discovered to have shown possibilities of leading to a scanning technology that could produce images. Great physicians like Raymond Damadian had noted a consistent difference in the NMR signals that had been obtained. He further developed NMR system for imaging and opted to take a test of the system with himself as the guinea pig (Appel et al. 2015). At the conclusion of his test, it was clear that NMR would be developed into a technique that could be used for medical imaging modality (Fiebach et al. 2004). The work received credit for the good curiosity that could lead to better ideas. After that, the idea of using magnetic field gradient to map the signals that emanated from the body followed.
The idea was developed by Paul Lauterbur. Many developments followed the first idea. By 1974, the first image of a finger was produced by Peter Mansfield, and later many developments followed. Then in the 1980s, NMR had been recognized as medical equipment. Several prototypes of the system were installed in various hospitals (Appel et al. 2015). At the time, the cloud of negativity had covered the world about nuclear wars following several years of world wars. The term nuclear was very misconstrued by the public, and the newly developed system had to be installed under the name magnetic resonance imaging to help prevent wrong conceptions. Since then, the medical sector has seen thousands of the equipment installed in several hospitals globally. Additionally, more scanners have been installed and are being installed every year to support various imaging processes. Understanding human brain had become the ultimate goal of doctors. The innovations of technologies such as x-ray brought some hope that it could be examined. Several illustrations that did not materialize were attempted. However, the brain is often made up of soft tissues that make it difficult and almost impossible to conduct conventional radiography. With the dangerous cerebrovascular disease like stroke, there is always a necessity to for proper brain examination because of the deadly nature of the disease (Appel et al. 2015). Despite the advancement in medication and treatments, it remains one of the deadly diseases behind cancer and heart diseases.
In the last couple of decades, MRI and Computed Tomography have been used to improve medical applications. They are currently considered the best imaging modalities that help to illustrate brain pathophysiology thus can be used to evaluate stroke accurately. The presence of CT and MRI has enhanced the accuracy of diagnosis (Appel et al. 2015). It thus enables a better understanding of pathophysiological processes in patients. Additionally, a good imaging modality should always provide the clinician with necessary answers to certain critical questions that arise during the examination. Mostly, there are four key issues that an imaging modality should provide their responses for the clinician to determine proper treatment. The key questions are; if there is hemorrhage, ischemic penumbra, if the artery is occluded, and the size of the irreversibly injured core. In the diagnosis of stroke, Computed Tomography is always preferred to magnetic resonance imaging. There are significant concerns regarding performance, and that is why CT is often preferred. Computed Tomography is always faster, more sensitive, and practical in detecting intracranial hemorrhage than MRI (Appel et al. 2015).
However, there are emerging questions as to whether CT is more effective in providing the answer to the diagnosis questions than RMI. Also, the trustworthy of the information submitted by both modalities are subject to scrutiny. The project attempts to unravel the reasons why Magnetic Resonance Imaging has taken over imaging of stroke patients in recent years despite the availability of computed tomography. The research also tends to find out whether MRI can be dependable as the primary imaging modality. To achieve these, we analyze the information that both the modalities can provide regarding a stroke patient to determine the why MRI has taken over.
The research attempts to find out how RMI has taken over stroke imaging in the recent years.
How has RMI taken over imaging of stroke patients in recent years?
Methodology
The project is a literature review report. The research methodology and resources used to facilitate the findings of the report are based on past publications about the literature. The project also used a review of literature that had been previously published. The evaluation of previous literature incorporated medical journals and books. The strategy for resource searching that was employed included studies and articles regarding RMI and CT electronic database search methodology in medical research that are indexed on Medscape and Pubmed-Medline. The sources are highly regarded biomedical literature sources. The sources were selected based on the area of research that is Magnetic Resonance Imaging for stroke analysis. The articles drew a comparison between RMI and CT on imaging of stroke by analyzing various strengths and advantages regarding sensitivity and accuracy in detecting different types of hemorrhage. The methodology used specific keywords for search engine feeding to find relevant sources. The keywords included; computed tomography, stroke imaging, hemorrhage diagnosis, magnetic resonance imaging, and thrombolysis.
Project structure and scope
The project uses comparative analysis to draw the diagnostic strengths of CT and MRI in a bid to offer an answer to the research question up which the project is based. The procedure uses evaluation techniques, CT-MR perfusion, and MR-CT Angiography to analyze various types of stroke, ischemia, and hemorrhage.
Literature Review
According to Davis et al. (2003) the first step in the diagnosis of stroke is detecting intracranial hemorrhage. The detection helps in differentiating hemorrhage from ischemic stroke. It is from the detection that a treatment path is defined. According to scholars and experts, Computed Tomography is considered the primary modality due to its high sensitivity to in hemorrhage detection (Davis et al. 2003). However, MRI that uses special sequence has been found to provide more accuracy in the detection of hemorrhage. The variation in sensitivity is determined by the type of stroke the patient has suffered. The modalities can provide varied answers depending on whether the patient has a chronic, subacute, and acute hemorrhage. Sometimes the detection levels can be determined by microbleeds or thrombolysis.
In the detection of acute intracranial hemorrhage, non-enhanced computed tomography is always the initial step for imaging. It is due to the high accuracy demonstrated by CT in intracranial hemorrhage. In computed tomography, intracranial blood often appears as a hyperattenuating area because of different x-rays attenuation. However, when the blood mixes with the brain tissue or cerebral blood flow, it can lead to hypoattenuation. According to Davis et al., (2003), computed tomography was tested for accuracy using 1420 patients. The patients underwent NCCT to have subarachnoid and intracerebral detected. The result produced 99.9% accuracy managing to miss only 0.1%. It is also possible that the accuracy if the process depends on the medical expert carrying out the test. In the account of the author, the detection accuracy was achieved by radiologists and neuroradiologists only since the clinicians dealing with emergency could more possibly result in errors (Marler & Leyden. 2010). Concerning hemorrhage detection, when MRI used a GRE T2, it was found to be very sensitive to hemorrhage detection.
When the accuracy of CT and MRI was compared in the detection of intracerebral hemorrhage, MRI proved to be more sensitive and accurate. It was also found to be accurate in detecting acute hemorrhage just as CT. In the study, 200 patients were tested. The outcome showed that RMI was overly sensitive and precise in any of the hemorrhage types. Additionally, only RMI detected acute hemorrhage whereas Computed Tomography did not detect (Davis et al. 2003).
In another examination, 200 patients were registered at both National Institute of Health and UCLA Medical Center for detection of chronic hemorrhage (Donnan et al. 2008). The results revealed that detection was more accurate using MRI. There were 52 chronic cases detected for MRI whereas CT did not detect any. Additionally, MRI even showed the chronic hemorrhage types that the patients had. MRI was able to detect 34 microbleeds, nine patients had a chronic hematoma, and 4 showed the hemorrhagic transformation. It was clearly evident that MRI was more sensitive to detecting chronic hemorrhage than computed tomography.
Conclusion
According to findings of the research that was based on previous medical journals, publications, and studies, MRI was accurate in detecting ischemia and hemorrhage types of stroke. Therefore, it was concluded that it can be for primary stroke imaging in patients who have suffered any stroke. In comparison, CT does not offer detailed information about hemorrhage. Computed Tomography was found not able to detect the types of hemorrhage whereas RMI detected them. The research found that RMI was at par and even exceeded CT in accuracy under special cases proved more specific. Moreover, RMI was proved to be more accurate and sensitive than CT in nearly all types of stroke. The research findings thus justify why MRI has taken over the imaging of stroke in the recent years.
Bibliography
Appel, C., Perry, L., & Jones, F. (2015). Testing a Protocol for a Randomized Controlled
Trial of Therapeutic versus Placebo Shoulder Strapping as an Adjuvant Intervention Early after Stroke. Occup. Ther. Int. Occupational Therapy International, 22(2), 71–84.
Davis S, Marc Fisher, Steven Warach. (2003) Magnetic Resonance
Imaging instroke.
Donnan GA, Fisher M, Macleod M, Davis SM. "Stroke". Lancet 2008
(9624): 1612–23. doi:10.1016/S0140-6736(08)60694-7. (Accessed: 16 April 2010)
Fiebach, J. B., Schellinger, P. D., Geletneky, K., Wilde, P., Hacke, W., Sartor, K., & Meyer, M.
(2004). MRI in acute subarachnoid haemorrhage; findings with a standardised stroke protocol. Neuroradiology, 46(1), 44–48
Marler, J., & Lyden, P. D. (2010). The NINDS t-PA for Acute Stroke Protocol.
Thrombolytic Therapy For Stroke, 297–308.
