MRI of the Musculoskeletal System: Advanced Applications using High and Ultrahigh Field MRI
MRI of the Musculoskeletal System: Advanced Applications using High and Ultrahigh Field MRI
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DOI：
10.1055/s-0035-1563735
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发表时间：
2015-09-01
影响因子：
1.4
通讯作者：
Regatte, Ravinder R.
中科院分区：
文献类型：
--
作者：
Alizai, Hamza;Chang, Gregory;Regatte, Ravinder R.
在过去的30年里，体内MRI彻底改变了肌肉骨骼疾病的诊断和治疗。传统上在1.5 T下进行，与较低场强相比，较高场强下的MRI具有几个优势，包括信噪比增加、空间分辨率更高、光谱学的光谱分辨率提高、X核成像的灵敏度提高以及图像采集时间缩短。然而，在更高场强下成像的物理学也提出了技术挑战。这些包括Bo和B1+场的不均匀性、用于高场的专用射频（RE）线圈的设计和构造、增加的化学位移和磁化率伪影、增加的RE能量沉积（比吸收率）、增加的金属伪影以及与较低场扫描仪相比弛豫时间的变化。十多年前，在优化高场（HF）（3 T）MRI时克服了这些挑战。HF MRI系统已获得临床肌肉骨骼成像的普遍认可，并已广泛用于肌肉骨骼解剖学和生理学研究。最近，人们对超高频（UHF）（7T）系统在肌肉骨骼中的应用越来越感兴趣。然而，必须克服与从1.5 T移动到3 T时遇到的技术挑战类似的技术挑战，以优化7 T肌肉骨骼成像。在这篇叙述性综述中，我们讨论了高频和超高频MRI系统带来的许多潜在机遇和技术挑战。我们强调最近的事态发展，在体内成像mnusculoskeletal组织，受益最大的高频成像，包括软骨，骨骼肌和骨。
In vivo MRI has revolutionized the diagnosis and treatment of musculoskeletal disorders over the past 3 decades. Traditionally performed at 1.5 T, MRI at higher field strengths offers several advantages over lower field strengths including increased signal-to-noise ratio, higher spatial resolution, improved spectral resolution for spectroscopy, improved sensitivity for X-nucleus imaging, and decreased image acquisition times. However, the physics of imaging at higher field strengths also presents technical challenges. These include Bo and B1+ field inhomogeneity, design and construction of dedicated radiofrequency (RE) coils for use at high field, increased chemical shift and susceptibility artifacts, increased RE energy deposition (specific absorption rate), increased metal artifacts, and changes in relaxation times compared with the lower field scanners. These challenges were overcome in optimizing high-field (HF) (3 T) MRI over a decade ago. HF MRI systems have since gained universal acceptance for clinical musculoskeletal imaging and have also been widely utilized for the study of musculoskeletal anatomy and physiology. Recently there has been an increasing interest in exploring musculoskeletal applications of ultrahigh field (UHF) (7 T) systems. However, technical challenges similar to those encountered when moving from 1.5 T to 3 T have to be overcome to optimize 7 T musculoskeletal imaging. In this narrative review, we discuss the many potential opportunities and technical challenges presented by the HF and UHF MRI systems. We highlight recent developments in in vivo imaging of rnusculoskeletal tissues that benefit most from HF imaging including cartilage, skeletal muscle, and bone.