Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, Missouri, USA.
Magn Reson Med. 2014 Jan;71(1):318-25. doi: 10.1002/mrm.24669. Epub 2013 Feb 19.
The objective of this study was to develop a new noncontrast method to directly quantify regional skeletal muscle oxygenation.
The feasibility of the method was examined in five healthy volunteers using a 3 T clinical MRI scanner, at rest and during a sustained isometric contraction. The perfusion of skeletal muscle of the calf was measured using an arterial spin labeling method, whereas the oxygen extraction fraction of the muscle was measured using a susceptibility-based MRI technique.
In all volunteers, the perfusion in soleus muscle increased significantly from 6.5 ± 2.0 mL (100 g min)(-1) at rest to 47.9 ± 7.7 mL (100 g min)(-1) during exercise (P < 0.05). Although the corresponding oxygen extraction fraction did not change significantly, the rate of oxygen consumption increased from 0.43 ± 0.13 to 4.2 ± 1.5 mL (100 g min)(-1) (P < 0.05). Similar results were observed in gastrocnemius muscle but with greater oxygen extraction fraction increase than the soleus muscle.
This is the first MR oximetry developed for quantification of regional skeletal muscle oxygenation. A broad range of medical conditions could benefit from these techniques, including cardiology, gerontology, kinesiology, and physical therapy.
本研究旨在开发一种新的非对比方法，直接定量区域性骨骼肌氧合。
本研究在 5 名健康志愿者中使用 3T 临床 MRI 扫描仪进行了该方法的可行性研究，分别在休息和持续等长收缩时进行检测。利用动脉自旋标记法测量小腿骨骼肌的灌注，利用基于磁化率的 MRI 技术测量肌肉的氧提取分数。
在所有志愿者中，比目鱼肌的灌注在休息时从 6.5±2.0 mL(100gmin)增加到运动时的 47.9±7.7 mL(100gmin)(P<0.05)。尽管相应的氧提取分数没有显著变化，但耗氧量从 0.43±0.13 增加到 4.2±1.5 mL(100gmin)(P<0.05)。在比目鱼肌中观察到类似的结果，但氧提取分数的增加大于比目鱼肌。
这是第一个用于定量区域性骨骼肌氧合的磁共振血氧定量法。这项技术可能会在许多医学领域受益，包括心脏病学、老年医学、运动科学和物理治疗。
