Advanced Knee ASL Imaging at 7T

7T 先进膝关节 ASL 成像

• 批准号: 10658674
• 负责人: Xiufeng Li
• 金额: $ 36.92万
• 依托单位: UNIVERSITY OF MINNESOTA
• 依托单位国家: 美国
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-06-01 至 2027-05-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10658674
• 关键词: Address; Adipocytes; Adolescent; Adult; Affect; Algorithms; Blood; Blood capillaries; Blood flow; Bone Development; Bone Marrow; Brain; Clinical; Clinical Research; Communities; Degenerative polyarthritis; Development; Diagnostic; Disease; Disease Progression; Echo-Planar Imaging; Etiology; Family; Functional disorder; Goals; Healthcare; Image; Knee; Knowledge; Lesion; Libraries; Logistic Regressions; Magnetic Resonance Imaging; Measures; Methodology; Methods; Modeling; Monitor; Noise; Nomograms; Osteochondritis Dissecans; Patients; Performance; Perfusion; Physiologic pulse; Physiological; Physiology; Play; Population; RF coil; ROC Curve; Research; Role; Safety; Signal Transduction; Slice; Speed; System; Technology; Therapy Evaluation; Time; Tissue Viability; Tissues; Uncertainty; arterial spin labeling; bone; bone repair; cohort; design; experience; healing; human model; imaging modality; imaging platform; imaging study; improved; insight; magnetic field; new technology; next generation; novel; prognostic performance; research study; response; safety assessment; skeletal disorder; software systems; tool; transmission process; treatment response; virtual; virtual model

Abstract Bone marrow perfusion can provide essential knowledge about bone physiology, improve our understanding of disease etiology and pathophysiology, assist the differentiation between normal and abnormal bone marrow, and assess the response to prescribed therapies. Arterial spin labeling (ASL) magnetic resonance imaging (MRI), as a noninvasive and non-contrast-enhanced approach, is well suited for longitudinal monitoring of disease progression and routine evaluation of therapy response. But as revealed by our recent studies, there exist technical challenges (e.g., low signal-to-noise (SNR) ratio due to significantly low perfusion in epiphyseal yellow bone marrow mainly consisting of fat cells with a sparse network of capillaries), and methodological limitations (e.g., single slice coverage and impractically long acquisition time for multi-slice imaging at 3T), hampering routine application of ASL imaging in the knee. Ultrahigh (≥7T) magnetic field can specifically benefit ASL imaging and overcome these challenges by increasing SNR, prolonging blood and tissue T1, and improving parallel imaging performance. However, the current clinically approved single-transmit MRI system and associated imaging methods are incapable of managing the transmit B1 (B1+) fields needed to realize the promised improvement in imaging quality, reliability, and robustness of 7T while existing RF coils are unable to provide adequate B1+ coverage for optimal ASL imaging. Our long-term goal is to develop and improve UHF imaging methods to better facilitate scientific research and clinical studies to improve the management of skeletal diseases and patient healthcare. The rationale is that the existing technical challenges for UHF imaging, including ASL, can be overcome or mitigated, ultimately to realize UHF potentials with promised benefits and superior imaging ability. The objective of this proposal is to develop an optimized, safe, and efficient pTx platform for knee ASL imaging (Aim 1), to develop and optimize pTx-integrated knee ASL imaging methods (Aim 2) and to explore their clinical potentials via studies with a cohort of JOCD patients, an ideal testbed for the developed methodologies. Accomplishing these aims will enable us to fully explore and utilize pTx potentials to overcome the existing technical challenges for knee ASL imaging at 7T. Once developed and optimized, the ASL methods, along with the pTx knee imaging platform, will provide clinicians and research community a powerful tool to enrich our insights into disease etiology and pathophysiology and improve the management of not only JOCD but also various impactful common knee diseases (e.g., osteoarthritis). Novel knowledge and experience from our pioneering development will speed up the maturity of new technology toward early approval of the next generation of clinical UHF MRI systems.

摘要 骨髓灌注可以提供有关骨生理学的基本知识，提高我们对 疾病病因学和病理生理学，帮助区分正常和异常骨髓， 并评估对处方治疗的反应。动脉自旋标记（ASL）磁共振成像 (MRI)作为一种非侵入性和非对比增强的方法，非常适合于纵向监测 疾病进展和治疗反应的常规评价。但根据我们最近的研究， 存在技术挑战（例如，由于骨骺灌注显著低，信噪比（SNR）低 黄色骨髓，主要由具有稀疏毛细血管网络的脂肪细胞组成），以及方法学 限制（例如，单层覆盖和在3T下用于多层成像不切实际的长采集时间）， 妨碍膝关节ASL成像的常规应用。超高（≥ 7T）磁场可特别受益 ASL成像，并通过增加SNR，延长血液和组织T1，以及改善 并行成像性能。然而，目前临床批准的单发射MRI系统和 相关联的成像方法不能管理实现成像所需的发射B1（B1+）场。 承诺改善7T的成像质量、可靠性和稳健性，而现有的RF线圈无法 为最佳ASL成像提供足够的B1+覆盖。我们的长期目标是发展和改善超高频 成像方法，以更好地促进科学研究和临床研究，以改善骨骼的管理 疾病和病人的医疗保健。其理由是，现有的技术挑战，超高频成像， 包括ASL，可以克服或减轻，最终实现具有承诺效益的UHF潜力， 上级成像能力。本提案的目标是开发一个优化、安全、高效的pTx平台 对于膝关节ASL成像（目标1），开发和优化pTx集成的膝关节ASL成像方法（目标2），以及 通过对JOCD患者队列的研究探索其临床潜力，这是开发 方法论。实现这些目标将使我们能够充分探索和利用pTx潜力， 7T下膝关节ASL成像的现有技术挑战。一旦开发和优化，ASL方法， 沿着pTx膝关节成像平台，将为临床医生和研究界提供一个强大的工具， 丰富我们对疾病病因学和病理生理学的见解，不仅改善JOCD的管理， 而且还包括各种影响性常见膝关节疾病（例如，骨关节炎）。新的知识和经验， 我们的开拓性发展将加速新技术的成熟， 临床UHF MRI系统的一代。