The effects of SENSE on PROPELLER imaging
Document Type
Article
Abstract
PURPOSE: To study how sensitivity encoding (SENSE) impacts periodically rotated overlapping parallel lines with enhanced reconstruction (PROPELLER) image quality, including signal-to-noise ratio (SNR), robustness to motion, precision of motion estimation, and image quality. METHODS: Five volunteers were imaged by three sets of scans. A rapid method for generating the g-factor map was proposed and validated via Monte Carlo simulations. Sensitivity maps were extrapolated to increase the area over which SENSE can be performed and therefore enhance the robustness to head motion. The precision of motion estimation of PROPELLER blades that are unfolded with these sensitivity maps was investigated. An interleaved R-factor PROPELLER sequence was used to acquire data with similar amounts of motion with and without SENSE acceleration. Two neuroradiologists independently and blindly compared 214 image pairs. RESULTS: The proposed method of g-factor calculation was similar to that provided by the Monte Carlo methods. Extrapolation and rotation of the sensitivity maps allowed for continued robustness of SENSE unfolding in the presence of motion. SENSE-widened blades improved the precision of rotation and translation estimation. PROPELLER images with a SENSE factor of 3 outperformed the traditional PROPELLER images when reconstructing the same number of blades. CONCLUSION: SENSE not only accelerates PROPELLER but can also improve robustness and precision of head motion correction, which improves overall image quality even when SNR is lost due to acceleration. The reduction of SNR, as a penalty of acceleration, is characterized by the proposed g-factor method.
Medical Subject Headings
Adult; Algorithms; Artifacts; Brain (anatomy & histology); Female; Humans; Image Enhancement (methods); Image Interpretation, Computer-Assisted (methods); Magnetic Resonance Imaging (methods); Male; Motion; Reproducibility of Results; Sensitivity and Specificity; Signal Processing, Computer-Assisted; Signal-To-Noise Ratio
Publication Date
12-1-2015
Publication Title
Magnetic resonance in medicine
E-ISSN
1522-2594
Volume
74
Issue
6
First Page
1598
Last Page
608
PubMed ID
25522132
Digital Object Identifier (DOI)
10.1002/mrm.25557
Recommended Citation
Chang, Yuchou; Pipe, James G.; Karis, John P.; Gibbs, Wende N.; Zwart, Nicholas R.; and Schär, Michael, "The effects of SENSE on PROPELLER imaging" (2015). Neuroradiology. 22.
https://scholar.barrowneuro.org/neuroradiology/22