Mason R P, Nunnally R L, Antich P P
Department of Radiology, University of Texas Southwestern Medical Center, Dallas 75235.
Magn Reson Med. 1991 Mar;18(1):71-9. doi: 10.1002/mrm.1910180109.
This work examines the variation with oxygen tension (pO2) of the individual spin-lattice relaxation times (T1) of the 19F resonances of the perfluorocarbon emulsion Oxypherol-ET (FC-43). A linear relationship between 1/T1 and pO2 has been confirmed for all four resonances at any specific temperature. Using a saturation recovery sequence, T1 has been successfully measured using surface coil NMR spectroscopy. This has facilitated measurement of T1 in vivo in a subcutaneous murine tumor. Mice were predosed with Oxypherol-ET emulsion: following complete vascular clearance of the perfluorocarbon, 19F signal was observed specifically from material sequestered in tissue, thus avoiding flow artifacts. Comparison of the pO2 estimated from each of the 19F resonances provided an internal consistency check. A pO2 = 0.1 +/- 2.2% was determined in a Meth-A murine tumor. When the mouse breathed carbogen (95% O2, 5% CO2) no significant change in tumor pO2 was detected, whereas the pO2 in the liver showed a distinct increase.
这项工作研究了全氟碳乳剂氧磷醇 - ET(FC - 43)的19F共振的各个自旋 - 晶格弛豫时间(T1)随氧分压(pO2)的变化。在任何特定温度下,已证实所有四个共振的1/T1与pO2之间存在线性关系。使用饱和恢复序列,已通过表面线圈核磁共振光谱成功测量了T1。这有助于在皮下小鼠肿瘤中进行体内T1测量。给小鼠预先注射氧磷醇 - ET乳剂:在全氟碳完全从血管清除后,专门从组织中隔离的物质中观察到19F信号,从而避免了流动伪影。比较从每个19F共振估计的pO2提供了内部一致性检查。在Meth - A小鼠肿瘤中测定的pO2为0.1±2.2%。当小鼠呼吸混合气(95% O2,5% CO2)时,未检测到肿瘤pO2有显著变化,而肝脏中的pO2则有明显增加。