IVIM-DWI评价静脉水化对碘对比剂所致家兔肾损伤的预防效果

Effect of venous hydration in preventing renal impairment after injection of iodinated contrast medium using IVIM-DWI

目的:采用IVIM-DWI评价注射碘对比剂前后静脉水化对碘对比剂所致肾脏损伤的预防效果。方法:36只健康雄性家兔,随机分成4组(每组9只)。A组:注射等量生理盐水;B组:碘对比剂注射前3h水化;C组:碘对比剂注射后3h水化;D组:注射等量碘对比剂。碘对比剂注射剂量为1 g I/kg,在注射后3 h、24 h、72 h对家兔进行肾脏IVIM-DWI检查。同时在对应时间点每组分别随机处死3只家兔,取右肾制作病理标本。结果:与A组相比,B、C、D三组在注射对比剂3 h肾脏皮、髓质D值、D~*值、f值均下降,B组皮质D值(5.91±0.66)×10^(-4)mm^2/s和髓质D值(5.35±0.82)×10^(-4)mm^2/s与对应C组皮质D值(4.90±0.93)×10^(-4)mm^2/s和髓质D值(4.29±0.73)×10^(-4)mm^2/s存在统计学差异(P<0.05),在24 h肾脏皮质D值、D~*值、f值降至最低,B组皮质D值(5.62±0.65)×10^(-4)mm^2/s、D~*值(7.86±0.48)×10^(-3)mm^2/s、f值(40.20±4.47)%与C组皮质D值(4.55±0.68)×10^(-4)mm^2/s、D~*值(6.82±0.40)×10^(-3)mm^2/s、f值(30.30±4.34)%存在统计学差异(P<0.05),72 h肾脏皮质D值、D~*值、f值呈现回升趋势,髓质D值、D~*值、f值下降至最低,B组髓质D值(5.09±0.21)×10^(-4)mm^2/s、D~*值(7.37±0.77)×10^(-3)mm^2/s、f值(34.10±5.14)%与C组髓质D值(4.01±0.58)×10^(-4)mm^2/s、D~*值(6.27±0.47)×10^(-3)mm^2/s、f值(25.70±3.35)%值存在统计学差异(P<0.05)。显微镜下观察病理切片,可见不同程度的肾小球和肾小管细胞混浊、肿胀、变性,集合管管型,间质充血,以D组病理损伤最重,B组病理损伤最轻。同时免疫组化水通道蛋白1(APQ1),D组表达增加最多,B组表达增加最少。结论:IVIM-DWI可有效评估注射碘对比剂前后静脉水化对碘对比剂所致的家兔肾损伤的保护作用,在注射碘对比剂前静脉水化、效果更好。

Objective:To investigate IVIM-DWI on evaluation of the effect of venous hydration before and after the injection of iodinated contrast medium in preventing renal impairment. Methods:36 healthy male rabbits were randomly and equally divided into four groups (n=9 each).Rabbits in group A were injected with equal amount of saline.Rabbits in group B were hydrated 3 hours before injecting iodinated contrast medium.Rabbits in group C were hydrated 3 hours after injecting iodinated contrast medium.Rabbits in group D were injected with equal amount of iodinated contrast medium without hydration before or after.MRI IVIM-DWI was performed on the rabbit kidneys 3 hours,24 hours and 72 hours after the injection of iodinated contrast mediumat a dose of 1g I/kg.Upon the completion of each corresponding scan,3 rabbits in each group were randomly killed and their right kidneys were harvested and made into specimen. Results:The D value,D^* value and f value of renal cortex in the renal cortex decreased 3h after the injection of contrast agent,and the D value (5.91±0.66)×10^-4mm^2/s and medulla D value (5.35±0.82)×10^-4mm^2/s of the B group and the corresponding C group.Cortical D value (4.90±0.93)×10^-4mm^2/s and medullary D value (4.29±0.73)×10^-4mm^2/s were statistically different ( P <0.05),at 24h,renal cortex D value,D^* value,f value decreased to the lowest,group B cortical D value (5.62±0.65)×10^-4mm^2/s,D^* value (7.86±0.48)×10^-4mm^2/s,f value (40.20± 4.47)% and group C cortical D value (4.55±0.68)×10^-3mm^2/s,D^* value (6.82±0.40)× 10^-3mm^2/s, f value (30.30±4.34)%.There was a statistical difference ( P <0.05),72h,renal cortex D value,D^* value,f showed a rising trend,medulla D value,D^* value,f value decreased to the lowest,group B medulla D value (5.09±0.21)×10^-4mm^2/s,D^* value (7.37±0.77)×10^-3mm^2/s,f value (34.10±5.14)% and group C medullary D value (4.01±0.58)×10^-4mm^2/s,D^* value (6.27± 0.47)× 10^-3mm^2/s,f value (25.70±3.35)% value statistics Learning differences ( P <0.05).Different pathological changes were revealed by microscopy in each group,such as muddy,swelling,and degeneration in glomerulus and renal tubules with cast in collection tubes and interstitial hyperemia,with the most serious damage in group D and the minimal in group B.Membrane staining of APQ1 could be identified with immunohistochemistry,with the highest expression in group D and the lowest expression in group B. Conclusion:IVIM-DWI can effectively evaluate the protective effect of hydration before and after injection of contrast mediumon rabbit kidneys from injury induced by iodinated contrast agent.Venous hydration before injection has the best effect.