Comparison of CT and MR imaging in ischemic stroke

Document Type:Thesis

Subject Area:Management

Document 1

Although both methods are effective in the determination of the presence and subtype of stroke, there has been continued debate on which method is the superior in the detection of acute stroke. Some researchers argue that MRI is better while others argue in favor of CT yet others feel that none of the two is superior over the other and that the technique used should depend on its availability and local clinical configuration. This study compares the two imaging techniques in the detection of ischemic stroke. The study first reviews the existing literature on the subject to get some important insights into the topic. Further, the researcher plans to conduct a study through a review of peer-reviewed articles from medical databases including AHRQ, CINAHL, Cochrane Review, and PubMed. Most importantly, the study makes use of PICO method in formulating the research question that is to be explored. The data collected will be presented using descriptive statistics for better visualization. Background According to Vymazal (619), cerebrovascular disease or stroke represents a major cause of global mortality with more than six million deaths being documented on an annual basis in all income groups. It has become the second largest cause of death only behind ischemic heart disease. Furthermore, cerebrovascular disease is a major source of morbidity. This is because “as many as 50 % of stroke survivors do not regain functional independence, and 20 % require institutional care 3 months after stroke onset” (Vymazal 619). The onset of stroke may be sudden or may be discovered after the arousal and may be accompanied by vomiting, headache, loss of consciousness or vertigo and can generally be classified into two; ischemic or hemorrhagic stroke.

Sign up to view the full document!

The treatment methods employed in these two types of stroke are different thus the early diagnosis, as well as the determination of the type of the stroke, is critical in early stage for better stroke management. Over years, a considerable number of tests have been developed to help in the determination of the presence and subtype of stroke. Despite the effectiveness of these tests, imagining has remained the preferred choice among physicians due to the sensitivity and specificity that it offers over the other methods. In addition, there is no other test that can be used to accurately differentiate between ischemic and hemorrhagic stroke (Vymazal 619). Two imaging techniques exist; Computed Tomography (CT) and Magnetic Resonance Imaging (MRI) (Audebert and Fiebach 1). Although both methods are effective in the determination of the presence and subtype of stroke, there has been continued debate on which method is the better in the detection of acute stroke.

Sign up to view the full document!

Some researchers such as Barber et al. and Audebert and Fiebach (1) argue that CT is better than MR while others such as Chalela et al. Audebert and Fiebach (1), study supports the use of CT over MR in acute stroke. The reveals that plain CT was the first one to be applied in clinical tests and formed the imaging backbone for the systemic thrombolysis. CT worked by excluding intracranial hemorrhage in the acute ischemic stroke patients. Subsequently, new modalities of CT including CT perfusion, CT angiography, and postcontrast CT were developed and are even more accurate than plain CT. Audebert and Fiebach (1), acknowledges MRI technology has opened new window of opportunities in determination of ischemic stroke because “MR provides better resolution of brain parenchyma, fewer artefacts particularly in the infratentorial brain region, earlier and more specific detection of ischemic brain damage via diffusion-weighted imaging (DWI) as well as a higher diagnostic accuracy for a variety of brain pathologies.

Sign up to view the full document!

further argues that gradient echo sequences are also available and can be used for the detection of hemorrhagic transformation with greater sensitivity than CT. However, the study further argues that with the current stroke guidelines used for thrombolysis administration both CT and MRI show great promise. However, neither of the techniques shows to be more efficacious than the other. Barber et al. further explains that the decision of which imaging technique to use in cases of acute stroke depend on the availability and feasibility of the technique. In the current times, CT has become the most commonly used method patients suspected of stroke. This is because CT is widely available, easy, fast, and less expensive when compared to MRI. However, Chela et al. states that CT is only sensitive to acute intracranial hemorrhage and not in acute ischemic stroke.

Sign up to view the full document!

Therefore, “CT is insufficiently sensitive for the diagnosis of acute ischemia, is subject to substantial inter-rater variability in interpretation, and might not be better than MRI for detection of acute intracranial hemorrhage” (Chela et al. study compared the use of MRI and CT in the detection of ischemic stroke and found both advantages and disadvantages for both methods as shown in table 1 below. Vymazal et al. argues that when ultrafast CT scanners that cover nearly the entire brain are used, the ability to diagnose ischemia as well as the salvageable tissues is more or less the same with both methods (ether Ct or MRI). The main disadvantage of CT is that it produces high radiation while MRI is complicated and a time-consuming method. Vymazal et al. A number of filters will be also be applied.

Sign up to view the full document!

The articles used will be limited to “scholarly/peer-reviewed” and will be also limited to the “2008-2010” (within the last ten years). Peer-reviewed sources will be used because they are more authoritative and promise more accurate information than articles that are not peer-reviewed. In addition, the study will be limited to the last 10 years due to fast-paced advancement in the CT and MR imaging technology. Older articles may give irrelevant information because it might be based on outdated technology that is not being employed anymore and thus resulting in inaccurate conclusions by the researcher. Finally, “detecting ischemic stroke” represents the desired outcome of the intervention and its comparison. The use of PICO in this study is therefore critical because it will help the researcher to evaluate all the relevant information required to make an accurate conclusion.

Sign up to view the full document!

Since the study is interested in comparing CT and MRI in detecting ischemic stroke, articles that only talk about one method without comparing it to the other techniques will be excluded from the study. In addition, studies that use patients whom neither CT nor MRI was done as subjects will be excluded from the study. Therefore, the inclusion criteria is that the article must compare both CT and MRI. et al. Imaging of the brain in acute ischaemic stroke: comparison of computed tomography and magnetic resonance diffusion-weighted imaging.  Journal of Neurology, Neurosurgery & Psychiatry 76. Chalela, Julio A. et al.

Sign up to view the full document!

From $10 to earn access

Only on Studyloop

Original template

Downloadable