Two-parametric prescan calibration of gradient-induced sampling errors for rosette MRI

• Published in: Magnetic resonance in medicine 2024-10
• Main Authors: Latta, Peter, Jiřík, Radovan, Vitouš, Jiří, Macíček, Ondřej, Vojtíšek, Lubomír, Rektor, Ivan, Standara, Michal, Křístek, Jan, Starčuk, Jr, Zenon
• Format: Article
• Language: English
• ISSN: 0740-3194; 1522-2594; 1522-2594
• DOI: 10.1002/mrm.30355

The aim of this study was to develop a simple, robust, and easy-to-use calibration procedure for correcting misalignments in rosette MRI k-space sampling, with the objective of producing images with minimal artifacts. Quick automatic calibration scans were proposed for the beginning of the measurement to collect information on the time course of the rosette acquisition trajectory. A two-parameter model was devised to match the measured time-varying readout gradient delays and approximate the actual rosette sampling trajectory. The proposed calibration approach was implemented, and performance assessment was conducted on both phantoms and human subjects. The fidelity of phantom and in vivo images exhibited significant improvement compared with uncorrected rosette data. The two-parameter calibration approach also demonstrated enhanced precision and reliability, as evidenced by quantitative relaxometry analyses. Adequate correction of data sampling is a crucial step in rosette MRI. The presented experimental results underscore the robustness, ease of implementation, and suitability for routine experimental use of the proposed two-parameter rosette trajectory calibration approach.