Department of Radiology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599-7510, USA.
J Magn Reson Imaging. 2011 Jun;33(6):1482-90. doi: 10.1002/jmri.22572.
To compare in-phase (IP)/out-of-phase (OP) single shot magnetization-prepared gradient-recalled-echo (MP-GRE) with a standard two-dimensional gradient-recalled-echo (2D-GRE), and to compare image quality of MP-GRE in cooperative and noncooperative subjects.
Ninety-six consecutive subjects (52 males, 44 females; mean age, 53.2 ± 16.7 years), both cooperative (n = 73) and noncooperative (n = 23) subjects who had MRI examinations including precontrast T1-weighted IP/OP MP-GRE with or without IP/OP 2D-GRE were included in the study. The sequences were independently qualitatively evaluated by two radiologists. Quantitative analysis of liver fat index, signal-to-noise ratio (SNR) and liver-lesion contrast-to-noise ratio (CNR) was also performed. Data were subjected to statistical analysis.
The visual detection of the presence or absence of liver steatosis showed no differences between 2D-GRE and MP-GRE imaging (k = 1). Minor differences were observed on image quality between MP-GRE and 2D-GRE in cooperative subjects, and between MP-GRE sequences performed in cooperative and noncooperative subjects. Liver fat index results were strongly positively correlated (r = .98; 95% confidence interval [CI] 0.97 to 0.98; P < .0001). Intercept (.14; 95% CI .13 to .15; P < .0001) and slope (.83; 95% CI .79 to .86; P < .0001) were statistically significant.
IP/OP MP-GRE and 2D-GRE comparably demonstrate the presence or absence of hepatic steatosis. Image quality of MP-GRE was also comparable to 2D-GRE, and was not substantially adversely affected if subjects were unable to cooperate with breathholding instructions.
比较同相位(IP)/反相位(OP)单次激发磁化准备梯度回波(MP-GRE)与标准二维梯度回波(2D-GRE),并比较合作和非合作受试者中 MP-GRE 的图像质量。
本研究纳入了 96 例连续受试者(52 名男性,44 名女性;平均年龄 53.2 ± 16.7 岁),包括有 MRI 检查的合作(n = 73)和非合作(n = 23)受试者,这些检查包括对比前 T1 加权 IP/OP MP-GRE 联合或不联合 IP/OP 2D-GRE。两位放射科医生对序列进行了独立的定性评估。还对肝脂肪指数、信噪比(SNR)和肝病变对比噪声比(CNR)进行了定量分析。数据进行了统计学分析。
2D-GRE 和 MP-GRE 成像在视觉检测肝脂肪变性的存在或不存在方面无差异(k = 1)。在合作受试者中,MP-GRE 和 2D-GRE 之间的图像质量存在轻微差异,在合作和非合作受试者中进行的 MP-GRE 序列之间也存在差异。肝脂肪指数结果呈强正相关(r =.98;95%置信区间 [CI] 0.97 至 0.98;P <.0001)。截距(0.14;95% CI 0.13 至 0.15;P <.0001)和斜率(0.83;95% CI 0.79 至 0.86;P <.0001)均具有统计学意义。
IP/OP MP-GRE 和 2D-GRE 均可显示肝脂肪变性的存在或不存在。MP-GRE 的图像质量也与 2D-GRE 相当,如果受试者无法配合屏气指令,其图像质量也不会受到实质性的不利影响。