目的 探讨肝胆特异性对比剂 钆塞酸二钠(Gd-EOB-DTPA)对正常家兔 肝脏磁共振扩散加权成像(Diffusion weighted imaging,DWI)的影响。方 法 六只健康新西兰家兔(体重2.13- 2.78kg)，于左侧耳缘静脉建立静脉通 道，麻醉后在3.0-TMR扫描仪上进行肝脏 磁共振DWI检查，静脉注射Gd-EOB-DTPA 20分钟后再次行DWI检查，成像参数保持 一致。工作站上观察DWI和ADC图像，测 量并比较增强前后家兔肝脏右外叶的表 观扩散系数(ADC)值和不同b值的DWI图肝 脏信噪比(SNR)的变化，组间比较采用配 对样本t检验。结果 家兔肝脏ADC值在静 脉注射Gd-EOB-DTPA 20分钟时较增强前 略下降((0.613±0.274)×10-3mm/s vs (0.637±0.302)×10-3mm/s))，两者差异 无统计学意义(t=0.680，P=0.501)。不 同b值的DWI图上，肝脏SNR在增强扫描前 后差异无统计学意义P值均＞0.05)。结 论 正常家兔肝脏的ADC值和SNR在静脉注 射Gd-EOB-DTPA 20分钟后无显著变化。

Objective To prospectively evaluate the effect of intravenous administration of gadoxetic acid disodium (Gd-EOB-DTPA) on diffusion weighted imaging (DWI) of normal rabbit's liver on 3.0-Tesla system. Methods Six health New Zealand rabbits were performed DWI on 3.0-Tesla system before and 20 minutes after injecting Gd-EOBDTPA (0.2ml/kg) through the left ear marginal vein with the same protocol. DWI with b values of 50, 400 and 800s/mm2 , and ADC values of right lateral lobe of liver were analyzed on MR Workstation. The Signal-to-noise ratio (SNR) on DWI and ADC values of the normal liver were measured and compared between these two group data by using the paired-samples t-test. Results ADC values of liver decreased slightly on 20 minutes post-contrast DWI than those of pre-contrast, (0.613±0.274)×10-3mm/ s vs (0.637±0.302)×10-3mm/s), but there was no significant difference (t=0.680, P=0.501) between them. SNRs of the liver parenchyma on DWI with different b values also showed no significant differences between 20 minutes post- and pre-contrast agent administration (P＞0.05). Conclusion ADC values and SNR of normal rabbit's liver on 20 minutes DWI after intravenously injecting Gd-EOB-DTPA had no significant changes compared with pre-contrast DWI.