Department of Diagnostic Radiology, Research Institute of Radiological Science, Yonsei University College of Medicine, Seoul, Korea.
J Magn Reson Imaging. 2012 Aug;36(2):405-10. doi: 10.1002/jmri.23620. Epub 2012 Mar 5.
To quantify liver T1 relaxation times before and after oxygen inhalation in patients with and without liver cirrhosis using a 3 Tesla (T) MRI.
Institutional Review Board approval and written informed consent were obtained. Ninety-two noncirrhotic patients and 87 patients with hepatitis B viral liver cirrhosis (72 Child-Pugh class A and 15 Child-Pugh class B or C) underwent MRI with a 3.0T system before and after the supply of 100% oxygen at a rate of 15 L/min by means of a nonrebreather ventilation mask for 3 min. T1 maps were acquired using three-dimensional spoiled gradient echo sequences with two different flip angles (2° and 14°) and a fixed TR/TE (2.54 ms/0.95 ms). Liver T1 values were obtained using a T1 processing tool (MapIT software). The mean baseline T1 values of three groups (control, Child-Pugh class A, and Child-Pugh class B/C) were compared using an analysis of variance test. Liver T1 value before and after oxygenation was compared using a paired t-test for each group.
The baseline liver T1 value was significantly higher in the control group (941 ± 136 ms) than in Child-Pugh A (858 ± 143 ms) and Child-Pugh B/C (783 ± 164 ms) group (P < 0.001 and P < 0.0001). The reduction in the liver T1 value after oxygen inhalation was significant in the control group (P = 0.012) but not significant in Child-Pugh class A (P = 0.079) and Child-Pugh class B/C (P = 0.752).
The baseline liver T1 relaxation time was significantly different between the patients with and without liver cirrhosis. The shortening effect of oxygen on the liver T1 value was significant in the control group but not in the cirrhotic patients.
利用 3 特斯拉（T）磁共振成像（MRI）在有和无肝硬化的患者中定量测量吸氧前后肝脏 T1 弛豫时间。
本研究获得了机构审查委员会的批准和书面知情同意。92 例非肝硬化患者和 87 例乙型肝炎病毒肝硬化患者（72 例 Child-Pugh 分级 A 和 15 例 Child-Pugh 分级 B 或 C）在使用非再呼吸通气面罩以 15 L/min 的速率供应 100%氧气 3 分钟前后，在 3.0T 系统上进行 MRI 检查。使用三维扰相梯度回波序列采集 T1 图谱，具有两个不同的翻转角（2°和 14°）和固定的 TR/TE（2.54 ms/0.95 ms）。使用 T1 处理工具（MapIT 软件）获得肝脏 T1 值。使用方差分析检验比较三组（对照组、Child-Pugh 分级 A 和 Child-Pugh 分级 B/C）的平均基线 T1 值。使用配对 t 检验比较每组吸氧前后的肝脏 T1 值。
对照组（941±136 ms）的基线肝脏 T1 值明显高于 Child-Pugh A 组（858±143 ms）和 Child-Pugh B/C 组（783±164 ms）（P<0.001 和 P<0.0001）。对照组吸氧后肝脏 T1 值降低有统计学意义（P=0.012），而 Child-Pugh 分级 A 组（P=0.079）和 Child-Pugh 分级 B/C 组（P=0.752）无统计学意义。
有和无肝硬化患者的基线肝脏 T1 弛豫时间有显著差异。氧对肝脏 T1 值的缩短作用在对照组中显著，但在肝硬化患者中不显著。
