In Vivo Meso‐Scale Whole‐Brain Quantitative Imaging With Tailored MRF on the NexGen 7T Scanner

作者：Xiaozhi Cao, Alexander Beckett, Congyu Liao, Erica Walker, Zheren Zhu, Yurui Qian, Mengze Gao, Nan Wang, Yimeng Lin, Lisong Gong, Matthew A. McCready, Zhixing Wang, Zhitao Li, An T. Vu, Samantha Ma, Gabriel Ramos‐Llordén, Qiyuan Tian, Adam Kerr, Yang Yang, David A. Feinberg, Kawin Setsompop · 发表于：Magnetic Resonance in Medicine · 年份：2025 · DOI：10.1002/mrm.70234 · 被引用次数：1 · 研究领域：Advanced MRI Techniques and Applications、Medical Imaging Techniques and Applications、Neurological disorders and treatments

ABSTRACT Purpose To push the speed and resolution limit of in vivo quantitative imaging and enable estimation of quantitative tissue parameters of subtle brain structures that were previously difficult to assess. Methods This study implemented an efficient quantitative imaging approach, 3D‐SPI MRF, on the NexGen 7T scanner equipped with a high‐performance head‐only gradient and 96‐channel receiver array. To address challenges associated with performing rapid mesoscale MRF on this system, acquisition and reconstruction mitigation methods were developed and incorporated into the MRF framework, including: (i) flip‐angle‐aware dictionary fitting to account for both B 1 + inhomogeneity and voxel‐specific RF frequency response, (ii) gradient imperfection corrections via Skope measurements that incorporates a new per‐TR trajectory rewinder compensation, (iii) incorporation of rapid B 1 + and B 0 mappings into the MRF sequence, and (iv) high‐temporal motion navigation. Results Whole‐brain T 1 and T 2 maps were obtained at 560‐μm isotropic resolution within 4 min, where ablation studies demonstrated the necessity of the various mitigation methods implemented in removing bias and artifacts. For comparison, MRF data were acquired using current state‐of‐the‐art method but limited to typical whole‐body gradient specifications to demonstrate that the proposed developments resulted in ∼3× shorter scan time while producing more accurate parameter maps. Data were also acquired at ∼3.8× smalle...