Introduction: Due to its complexity, the magnetic resonance imagining (MR) is susceptible to artifacts. They can appear in MR images as different shapes or objects. Some of them can seriously affect diagnostic image quality, while others may simulate or be confused with different pathology. Artifacts are caused by various factors, and most of them can be identified and eliminated quickly and effectively. If elimination is not possible, some methods allow radiographers to reduce negative influence on MR images. Purpose: To describe and systematically classify the most common MR artifacts, to present an overview of mitigation and correction methods, and to determine which method is the most appropriate for remedying each type of artifact. Methods: The thesis presents an overview of the most common MR artifacts based on literature review and descriptive research. We analyzed MR scans, corrupted with already identified artifacts, using a picture archiving and communication system (PACS), used by Ljubljana Medical Center. We reviewed literature, found in DiKUL, Pubmed, Pubmed CENTRAL and ScienceDirect databases. Results: Motion artifacts are usually reduced by fixation with straps, by using series of additional saturation pulses, and by flow compensation technique. Aliasing artifacts can be eliminated by increasing the field of view. Alternatively, they can also be prevented by anti-aliasing techniques, such as no-phase wrap and phase oversampling. Approaches to minimizing susceptibility artifacts include shortening the echo time, the use of faster pulse sequences and the use of thinner slices. Metal artifacts can be avoided by proper patient preparation before the MR procedure. When metallic implants are present in the MR examination, their impact should be minimalized by a metal artifact reduction sequence (MARS). To reduce the slice-overlap artifact, radiographers should ensure that the slices do not overlap in the spinal canal. Alternatively, they could acquire the odd slices first and then the even slices. Chemical shift artifacts can be alleviated by increasing the receiver bandwidth or the field of view, and by fat saturation. Zipper artifact can be avoided by ensuring that the scanner room door is shut during imaging. Gibbs-ringing artifacts are reduced by high pass filter that removes the low spatial frequencies from k-space. Discussion and conclusion: MR artifacts can be alleviated or eliminated by numerous methods of varying success. To optimize clinical image quality, it is crucial that radiographers understand the causes of artifacts, their characteristics, and mitigation and correction methods, so that they opt for the most appropriate method for alleviating each type of artifact.
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