A Novel MRI Technique for Enhanced Multi-Parameter Mapping

Markus Zimmermann, Zaheer Abbas, Yannic Sommer, Alexander Lewin, Shukti Ramkiran, Jörg Felder, Wieland A. Worthoff, Ana-Maria Oros-Peusquens, Seong Dae Yun, N. Jon Shah

1st September 2024

INM-4 researchers are pleased to announce the introduction of a new approach for the simultaneous mapping of multiple quantitative MRI parameters at ultrahigh field strength. The method, known as QRAGE, provides detailed insights into water content, T1, T2*, and magnetic susceptibility.

QRAGE utilises the recently developed multi-echo MPnRAGE sequence, enabling the acquisition of 171 distinct contrast images within a short time frame. To achieve this high level of efficiency, the novel MIRAGE2 reconstruction method is employed, leveraging prior knowledge of temporal signal evolution. The result is precise parameter maps derived through advanced postprocessing techniques.

Extensive performance validation was conducted through simulations, phantom studies and in vivo experiments. In vivo brain measurements demonstrated minimal deviations from reference methods, with exceptional precision across all mapped parameters. QRAGE achieves whole-brain coverage at a 1-mm isotropic resolution in just over 7 minutes, on par with existing MRI techniques.

QRAGE introduces an efficient solution for comprehensive multi-parameter mapping at ultrahigh field strength, delivering results in the same time frame as a standard MP2RAGE scan while offering comparable image contrast. With its potential to seamlessly replace the widely used MP2RAGE sequence in neuroscientific research, QRAGE is poised for broad adoption, especially as advancements continue to reduce reconstruction times.

A remaining challenge lies in the high computational demands required for the image reconstruction process. This component is critical, as it involves complex algorithms that process a vast amount of data to ensure the quality of the acquired images. To address this, the team is actively developing a novel AI-based image reconstruction technique, which aims to significantly reduce the computational burden, thereby shortening the reconstruction time and making the QRAGE method even more accessible for widespread use in neuroscientific research.

Original Publication: QRAGE—Simultaneous multiparametric quantitative MRI of water content, T1, T2*, and magnetic susceptibility at ultrahigh field strength

Last Modified: 04.09.2024