Steer-PROP: a GRASE-PROPELLER sequence with interecho steering gradient pulses
| Autor: | Novena Rangwala, Xiaohong Joe Zhou, Girish Srinivasan |
|---|---|
| Rok vydání: | 2017 |
| Předmět: |
Adult
Computer science Image quality Parallel Article 030218 nuclear medicine & medical imaging 03 medical and health sciences 0302 clinical medicine Robustness (computer science) Image Interpretation Computer-Assisted medicine Humans Radiology Nuclear Medicine and imaging Simulation medicine.diagnostic_test Phase correction Echo-Planar Imaging Phantoms Imaging Brain Pulse sequence Magnetic resonance imaging Repetition Time Spin echo Female Algorithm 030217 neurology & neurosurgery Algorithms |
| Zdroj: | Magnetic resonance in medicine. 79(5) |
| ISSN: | 1522-2594 |
| Popis: | PURPOSE This study demonstrates a novel PROPELLER (periodically rotated overlapping parallel lines with enhanced reconstruction) pulse sequence, termed Steer-PROP, based on gradient and spin echo (GRASE), to reduce the imaging times and address phase errors inherent to GRASE. The study also illustrates the feasibility of using Steer-PROP as an alternative to single-shot echo planar imaging (SS-EPI) to produce distortion-free diffusion images in all imaging planes. METHODS Steer-PROP uses a series of blip gradient pulses to produce N (N = 3-5) adjacent k-space blades in each repetition time, where N is the number of gradient echoes in a GRASE sequence. This sampling strategy enables a phase correction algorithm to systematically address the GRASE phase errors as well as the motion-induced phase inconsistency. Steer-PROP was evaluated on phantoms and healthy human subjects at both 1.5T and 3.0T for T2 - and diffusion-weighted imaging. RESULTS Steer-PROP produced similar image quality as conventional PROPELLER based on fast spin echo (FSE), while taking only a fraction (e.g., 1/3) of the scan time. The robustness against motion in Steer-PROP was comparable to that of FSE-based PROPELLER. Using Steer-PROP, high quality and distortion-free diffusion images were obtained from human subjects in all imaging planes, demonstrating a considerable advantage over SS-EPI. CONCLUSION The proposed Steer-PROP sequence can substantially reduce the scan times compared with FSE-based PROPELLER while achieving adequate image quality. The novel k-space sampling strategy in Steer-PROP not only enables an integrated phase correction method that addresses various sources of phase errors, but also minimizes the echo spacing compared with alternative sampling strategies. Steer-PROP can also be a viable alternative to SS-EPI to decrease image distortion in all imaging planes. Magn Reson Med 79:2533-2541, 2018. © 2017 International Society for Magnetic Resonance in Medicine. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|
Plný text