Department of Radiology University of Pennsylvania Health System 3400 Civic Center Blvd, Penn Tower Lobby Level Philadelphia, PA 19104, USA.
Radiology. 2012 Feb;262(2):375-7. doi: 10.1148/radiol.11112449.
As initially reported by Ogawa et al (1), the magnetic resonance (MR) imaging T2* blood oxygen level–dependent (BOLD) signal is sensitive to blood oxygen concentration; however, this signal is also sensitive to a number of other normal and abnormal tissue features. As a result, T2* imaging alone cannot be used to accurately measure vascular oxygenation, much less tissue oxygenation. However, with separate MR imaging measurements of other tissue factors influencing T2*, it might be possible to noninvasively image local tissue oxygen. Such a capability could be of great clinical importance, not only in patients with hypoxic or ischemic disease states, but also in patients with other pathologic conditions that have abnormal respiratory metabolism, such as cancer.
正如 Ogawa 等人最初报道的（1），磁共振（MR）成像 T2血氧水平依赖（BOLD）信号对血氧浓度敏感；然而，这个信号也对许多其他正常和异常的组织特征敏感。因此，仅凭 T2成像不能准确测量血管氧合，更不能测量组织氧合。然而，通过对影响 T2*的其他组织因素进行单独的 MR 成像测量，可能可以无创性地成像局部组织氧。这种能力具有重要的临床意义，不仅在缺氧或缺血性疾病状态的患者中，而且在其他具有异常呼吸代谢的病理状况（如癌症）的患者中也是如此。
