Year: 2023
Type: preprint
Abstract: Magnetic resonance imaging (MRI) generates a radiofrequency field (B1) to frequency encode the object being imaged. Deviations from the nominal B1 field produce artifactual intensity nonuniformity (INU) across the image, which is problematic, especially for automated analyses that assume a tissue is represented by voxels of similar intensity throughout the image (Belaroussi et al. 2006). These artifacts are particularly exacerbated by receiver coil failures. Such events are difficult to capture as they tend to be short-lived and sporadic. In brain blood-oxygen-level-dependent (BOLD) functional MRI (fMRI), B1 field dynamics is usually visualized with a video of the scan to spot signal intensity changes, but this method is time-consuming and error-prone, as the human observer needs to keep focus during the whole video. Here, we showcase a visualization tool to assess B1 field dynamics and a derived summary metric to efficiently detect low spatial-frequency artifacts, such as transient INU.
Language: English
Subfield: Radiology, Nuclear Medicine and Imaging
Field: Medicine
Domain: Health Sciences
Open Access status: green
OpenAlex ID: W4316669479