Multistep phase difference phase contrast imaging

✍ Scribed by M. J. Reina Lamothe; Brian K. Rutt

• Publisher: John Wiley and Sons
• Year: 1997
• Tongue: English
• Weight: 884 KB
• Volume: 7
• Category: Article
• ISSN: 1053-1807
• DOI: 10.1002/jmri.1880070510

✦ Synopsis

Abstract

A new technique for multistep phase‐contrast image processing is presented. The N‐step method consists of simply forming the linear average of the N — 1 adjacent phase‐difference signals. It has similar noise reduction properties as other multistep techniques, but the simplicity of the noise variance of the N‐step technique allows intuitive insight into phase‐difference phase‐contrast processing and noise reduction, which can aid in the design of efficient and improved phase‐contrast imaging sequences. As well, the computational simplicity of the N‐step phase‐difference technique compared with any other known multistep technique is advantageous. Like other multistep techniques, it has far more efficient noise reduction properties than simple two‐step, multiple average phase‐contrast imaging, even when normalized for total scan time. A three‐step phase‐difference velocity image has 50% less variance than an image acquired with two steps and two scans averaged but is obtained in 25% less scan time. Given its advantages, it should now be the chosen technique for increasing velocity‐to‐noise and contrast‐to‐noise ratios in all phase‐difference phase‐contrast clinical applications.