Investigation of vibration‐induced artifact in clinical diffusion‐weighted imaging of pediatric subjects. Issue 12 (9th September 2015)

• Record Type: Journal Article
• Authors: Berl, Madison M.; Walker, Lindsay; Modi, Pooja; Irfanoglu, M. Okan; Sarlls, Joelle E.; Nayak, Amritha; Pierpaoli, Carlo
• Is Part Of: Human brain mapping. Volume 36:Issue 12(2015:Dec.)
• Page Start: 4745
• Page End: 4757
• Publication Date: 2015-09-09
• Subjects: diffusion tensor imaging -- weight -- position -- quality -- regrowth; Brain mapping -- Periodicals; 611.81
• DOI: 10.1002/hbm.22846
• Languages: English
• ISSNs: 1065-9471

Abstract

Abstract: It has been reported that mechanical vibrations of the magnetic resonance imaging scanner could produce spurious signal dropouts in diffusion‐weighted images resulting in artifactual anisotropy in certain regions of the brain with red appearance in the Directionally Encoded Color maps. We performed a review of the frequency of this artifact across pediatric studies, noting differences by scanner manufacturer, acquisition protocol, as well as weight and position of the subject. We also evaluated the ability of automated and quantitative methods to detect this artifact. We found that the artifact may be present in over 50% of data in certain protocols and is not limited to one scanner manufacturer. While a specific scanner had the highest incidence, low body weight and positioning were also associated with appearance of the artifact for both scanner types evaluated, making children potentially more susceptible than adults. Visual inspection remains the best method for artifact identification. Software for automated detection showed very low sensitivity (10%). The artifact may present inconsistently in longitudinal studies. We discuss a published case report that has been widely cited and used as evidence to set policy about diagnostic criteria for determining vegetative state. That report attributed longitudinal changes in anisotropy to white matter plasticity without considering the possibility that the changes were caused by this artifact. Our study underscores the need to check for the presence of this artifact in clinical studies, analyzes circumstances for when it may be more likely to occur, and suggests simple strategies to identify and potentially avoid its effects. Hum Brain Mapp 36:4745–4757, 2015 . © 2015 Wiley Periodicals, Inc.