3.0T MR反转时间对流入反转恢复序列门静脉成像质量的影响

目的 探讨3.0T MR 反转时间（TI）对流入反转恢复序列（IFIR）门静脉系统非对比增强图像质量的影响。方法 对健康志愿者 31名（正常组）、门静脉高压患者12例（门静脉高压组）采用不同的TI行冠状位IFIR序列扫描。评估采用不同TI所得的IFIR图像的门静脉主干SNR、主动脉SNR、肝脏组织SNR、门静脉主干CNR，根据门静脉及其分支显示清晰程度进行评分。对上述指标的比较采用单因素方差分析或配对t检验。结果 两组受检者不同TI图像的门静脉主干SNR和CNR差异均无统计学意义（P均>0.05）。正常组肝脏组织SNR、主动脉SNR差异有统计学意义（P均<0.05），不同TI门静脉图像分支评分差异无统计学意义（P>0.05）。门静脉高压组不同TI图像的肝内分支评分构成比差异有统计学意义（P=0.012）；选择900 ms TI时，门静脉高压组门静脉主干SNR和CNR、图像评分均低于正常组，TI为1100 ms时，两组图像评分的差异无统计学意义（P>0.05）。结论 对于正常受检者，TI为700 ms时既能得到较好的背景压制的图像，又能保证显示门静脉远端细支血管；而对于门静脉高压患者，选择TI为1100 ms更有利于门静脉分支血管的显示。

Effect of inversion time on 3.0T MR inflow inversion recovery imaging of portal vein

Objective To evaluate the effect of inversion time (TI) on 3.0T MR inflow inversion recovery (IFIR) imaging of portal vein. Methods Totally 31 healthy volunteers (normal group) and 12 patients with portal hypertension (portal hypertension group) underwent coronal IFIR sequence with various TI. The SNR of the main portal vein, aorta and liver, CNR of the main portal vein were analyzed. Visualization scores of portal venous branches in different TI were also evaluated. ANOVA and paired t test were applied for statistical analysis. Results In the two groups, SNR and CNR of the main portal vein had no significant differences under different TI (all P>0.05). The SNR of aorta and liver had significant differences in normal group (P<0.05). The difference of visualization score with various TI was not statistically significant (P>0.05), while it was statistically significant in portal hypertension group (P=0.012). When TI was set to 900 ms, the SNR and CNR of the main portal vein, visualization score in portal hypertension group were lower than those in normal group, however, when TI was set to 1100 ms, visualization score between the two groups had no significant differences (P<0.05). Conclusion TI set to 1100 ms is helpful to display of portal vein branch vessels for portal hypertension patients, while 700 ms can be considered as the best choice for healthy persons.