Abstract #1218

Improved Time-Resolved, 3D Phase Contrast Imaging through Variable Poisson Sampling & Partial Respiratory Triggering

Marcus T. Alley¹, Mark J. Murphy², Kurt Keutzer², Michael Lustig², Shreyas S. Vasanawala¹

¹Radiology, Stanford University, Stanford, CA, United States; ²Electrical Engineering & Computer Science, University of California, Berkeley, CA, United States

Time-resolved 3-dimensional phase-contrast MR imaging (4D-PC MRI) has become more clinically viable with the advent of parallel imaging. However, undersampling patterns suitable for GRAPPA-like reconstructions often result in coherent artifacts in the final images. Here we demonstrate the use of variable density Poisson-disc/ellipse pseudorandom sampling in conjunction with the L1-SPIRiT compressed sensing reconstruction implemented on general-purpose graphics processors (GPGPU). The combined approach provides improved image quality, better artifact reduction in clinically viable acquisition and reconstruction times. In addition, we have implemented a partial respiratory triggering approach to reduce breathing artifacts with a minimal increase in scan-time.