Comparison between CT scan and MRI in Detection of Transient Ischemic Attack

Background 4 2. Pathophysiology 4 2. Modalities to diagnose TIA 5 3. PICO question 6 4. Methodology 6 5. In order to ensure that the research was reliable and valid, a quality methodology was established which included the following, Journal of the Royal Society of Medicine J Neural Neurosurg Psychiatry, Journal of the Royal Society of Medicine (Eur Neurol) and Journal of the Royal Society of Medicine (Cerebrovascular Diseases: Eur Neurol). All these articles were the most recent journals which were relating to the research topic. In order to know the comparison of MRI imaging and CT Scan in TIA patients the results which were obtained from the four articles was as follows, The number of those who had MRI was between 40% and 60%, those who had CT scan done on them was between 65%-85%, those patients who had repeated imaging were between 5% and 8% and those who were diagnosed with TIA clinically during examination were between 10% to 35%.

Proper taking of history and physical examination of the patient who presents with symptoms of TIA is considered in decreasing the transition to stroke. In detection of ischemic lesions, MRI is more sensitive than CT scans. The ischemia or the shortage of the blood supply can be due to several reasons. For example, in cardiac arrest patients, people may experience ischemic stroke due to oxygen shortage only. Whereas some people may have ischemic stroke due to glucose shortage only like in patients who take overdose of insulin injection. The neuronal cells damage that happened usually may affect the functional area that involve in the brain stroke and then patient complains of signs and symptoms related to that functional part like loss of vision, difficulty in speaking and weakness in moving of legs or arms.

The transient ischemic attack has almost same way of occurring but the flow of blood can return normal within several minutes and the signs and symptoms are the same for a short period of time. Also acknowledges MRI technology has opened new window of opportunities in determination and subtype ischemic attack because “MRI 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. ” However, Audebert and Fiebach (2015) further argue that despite the clear advances in MRI, MRI is time-consuming and that in a typical ischemic stroke patient, the fasted imaging method is mandatory so as to avoid a delay in treatment.

Therefore CT has continued to remain the go-to method of ischemic stroke in most health facilities because it is much faster and inexpensive when compared to MRI. PICO question The research question for this study is written in the PICO format. The research question is thus presented as; “In patients with transient ischemic attack-like symptoms (P), how effective is CT (I) versus MRI (C) at detecting transient ischemic attack (O)? From the above question “patients with transient ischemic attack-like symptoms” represents the population of the study, and CT presents the intervention available. The databases used will include but not limited to Agency for Healthcare Research and Quality (AHRQ), Cumulative Index of Nursing and Allied Health Literature (CINAHL), Cochrane Review, PubMed. Only medical databases would be used because they promise to give more accurate, relevant, and authoritative information than other nonmedical or general databases.

The researcher will employ the advanced search technique by the use of keywords in searching for the articles to be used in the study. The key words to be used will include; “magnetic resonance imaging” or “MRI” or “computed tomography” or CT and “transient” or “ischemic” and “attack”. A number of filters will be also be applied. 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. Another inclusion relates to transient ischemic stroke. Therefore, the article should focus on the ability of the technique to detect transient ischemic stroke and not any other stroke. Therefore, in summary, the inclusion criteria include; the article must be published within the last 10 years (2008 to 2017), must compare CT and MRI, and finally, the comparison should be in relation to ischemic stroke.

patients had MRI scans and approximately 14 patients were followed up for several weeks later after the scan was performed on them. Those cases which were classified as mimics of the strokes were 36, 27 patients had CT scans and those patients who had Doppler carotid were 31. Out of the 65 patients, only 3 who had their diagnoses changed after MRI imaging. They also conduct another study where they had a larger number of 100 patients who were attending the TIA clinic between 1-2 months during the study, with the same collection of data they found out that 38% of those patients had dual cerebral imaging, CT scan, MRI which followed 59% of these patients were followed up in the TIA clinic (Marshall 2014). When adding up the database, those patients who had imaging repeated were 34% and 53% were give a follow-up schedule in the TIA clinic.

Another study which was conducted by Francois et al (2013), magnetic resonance imaging versus computed tomography in TIA and minor stroke they preferred MRI as the primary modality to be used when investigating TIA. Those patients who were included in the study were 347. In DWI 193 patients out of 347 which was 56%, acute ischemic lesions were very common than 41 patients out of 347, 12% who were on CT scan. They also observed that there was 51% (155 out of 306) CT negative patients when the MRI was performed on them the results were positive. When considering using MRI as the primary modality when investigating TIA patients, in terms of sensitivity there were 38 cases which were CT positive versus 193 MRI cases which were positive. The effectiveness of all these modalities was based on the periods of time.

At the start time, the baseline was very poor for both CT and DWI. However, when the time reached 24 hours it was excellent (Albers et al 2016 p. In this study, the results showed that when detecting and establishing signs of TIA, DWI and CT are comparable. But this does not imply that these two investigations are the same. The CT scan did not identify any pathology in 154 patients, for those which it detected having lesions were 6 patients which were in the anterior and one in the posterior. For the DWI it was able to establish in the CT scan in only 2 patients in the 7, where one was in the anterior and 1 in the posterior (Prichard et all 2014 p 52). In this study, CT scan is always used as baseline or initial imaging.

However, it does not provide important clinical results in relation to those patients who have been suspected to have ischemic lesions. The major difference which exit between MRI and the CT scan is on the basis of ability of identifying very small lesions in TIA. The research was carried out in a population which have different people; this makes it suitable for implementation in the healthcare field. For the interpretation and analysis of results for data collected in the research, there are many limitations which were to be considered. The first limitation is that there was big challenge in accessing some articles. Secondly, some articles were written in other languages other than English. Recommendations for further research This research paper focused on the comparison of computed tomography and magnetic resonance in detection of transient ischemic attack.

Alberta Stroke Programme Early CT Score. Lancet 2016;355:360–4. Barber PA, Darby DG, Desmond PM, et al. Identification of major ischemic change. Diffusion-weighted imaging versus computed tomography. Jeban G and I Harri J: Should MRI or CT can be used as the primary modality in Transient Ischemic Attack. Q J Med 2011; 33: 309–324. Marshall J: The natural history of transient ischaemic cerebrovascular attacks. Q J Med 2014; 33: 309–324. Moreau F, Modi J, Almekhlafi M, et al. New NICE guideline on acute stroke and TIA: need for major changes in delivery of stroke treatment. Heart 2009; 95: 841–843. Appendix 1: Search strategy Database Keywords No of articles found Articles selected Journal of the Royal Society of Medicine Should MRI or CT scan be used as the primary modality in TIA >3 articles Randomly one J Neural Neurosurg Psychiatry Imaging of the brain in acute ischaemic stroke: A comparison of MRI and CT scan >1articles one Journal of the Royal Society of Medicine (Eur Neurol) Brain imaging in patients with TIA: A comparison of CT scan and MRI >5 articles Randomly one Journal of the Royal Society of Medicine (Cerebrovascular Diseases: Eur Neurol) MRI versus CT scan in TIA and Minor stroke 1 article one Appendix 2 Evidence table Title of article Authors/ Year Of publication Type Of study Summary (relevant to the research) Should MRI or CT scan be used as the primary modality in TIA Jeban and Harri (2011) Retrospective cohort study - The four articles which I selected showed high relevance to my aims and broad objectives of the research paper.

In all articles, my focus aimed in fulfilling the inclusion criteria (All those patients who were suffering from TIA who were alive and willing to participate in the study,). All evidences which were gathered were analyzed critically using CASP tool for the corresponding study type.