Investigation of vibration-induced artifact in clinical diffusion-weighted imaging of pediatric subjects.
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.
Division of Pediatric Neuropsychology, Washington, District of Columbia, Children's Research Institute, Children's National Health System, Washington, DC.
Madison M
MM
Berl
Program on Pediatric Imaging and Tissue Sciences, Eunice Kennedy Shriver National Institute of Child Health and Human Development, Bethesda, MD.
Lindsay
L
Walker
Program on Pediatric Imaging and Tissue Sciences, Eunice Kennedy Shriver National Institute of Child Health and Human Development, Bethesda, MD.
Pooja
P
Modi
Program on Pediatric Imaging and Tissue Sciences, Eunice Kennedy Shriver National Institute of Child Health and Human Development, Bethesda, MD.|Henry Jackson Foundation, Bethesda, Maryland.
M Okan
MO
Irfanoglu
NMRF, NINDS, National Institutes of Health, Bethesda, Maryland.
Joelle E
JE
Sarlls
Program on Pediatric Imaging and Tissue Sciences, Eunice Kennedy Shriver National Institute of Child Health and Human Development, Bethesda, MD.|Henry Jackson Foundation, Bethesda, Maryland.
Amritha
A
Nayak
Program on Pediatric Imaging and Tissue Sciences, Eunice Kennedy Shriver National Institute of Child Health and Human Development, Bethesda, MD.|Center for Neuroscience and Regenerative Medicine, Uniformed Services University of the Health Sciences, Bethesda, Maryland.
Carlo
C
Pierpaoli
D000293:Adolescent; D000328:Adult; D000704:Analysis of Variance; D016880:Anisotropy; D016477:Artifacts; D001921:Brain / Q000473:pathology*; D001931:Brain Mapping; D016009:Chi-Square Distribution; D002648:Child; D016208:Databases, Factual / Q000706:statistics & numerical data; D038524:Diffusion Magnetic Resonance Imaging; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008297:Male; D010372:Pediatrics; D012189:Retrospective Studies; D014732:Vibration / Q000009:adverse effects*
diffusion tensor imaging; position; quality; regrowth; weight