基于MRI技术定量测量单侧肾动脉狭窄动物模型肾脏氧摄取分数的初步研究  

Feasibility of non-invasively quantitative measurements of Intrarenal oxygen extraction fraction(OEF) in rabbits with unilateral renal artery stenosis using MRI

作　　者：张晓东[1] 米悦[2] 王晶[3] 孙艳[1] 张锐[4] 吴静云[1] 王成彦[4] 赵凯[1] 罗健[1] 杨学东[1] 张珏[4] 王霄英[1,4] 

机构地区：[1]北京大学第一医院医学影像科,北京100034 [2]北京大学第一医院泌尿外科,北京100034 [3]国家食品药品监督管理总局医疗器械技术评审中心,北京100044 [4]北京大学前沿交叉学科研究院功能成像中心,北京100871

出　　处：《放射学实践》2015年第5期519-524,共6页Radiologic Practice

基　　金：高等学校博士学科点专项科研基金(20110001120053);首都卫生发展科研专项项目(2011-4021-02)资助

摘　　要：目的:验证基于血氧水平依赖(BOLD)的多回波梯度自旋回波(MEGSE)序列无创定量测量肾脏氧摄取分数(OEF)等氧代谢指标参数的可行性。方法:15只健康新西兰大白兔入组研究。对每只兔子施行左肾动脉部分结扎手术以造成单侧肾动脉狭窄(RAS)动物模型。行MRI扫描采集3个不同时刻的MEGSE数据,分别为基础状态、RAS术后30min(RAS-30min)和RAS术后60min(RAS-60min),以获得肾脏动脉狭窄造模前后的肾脏OEF值。结果:15只兔子均造模成功。在RAS术前测得的肾脏基础状态下OEF值为(0.36±0.08)(皮质)和(0.39±0.11)(髓质)。RAS术后30min和60min测得的OEF显著增大分别为(0.46±0.14)(皮质,RAS-30min,P<0.05)、(0.51±0.12)(髓质,RAS-30min,P<0.05)、(0.46±0.13)(皮质,RAS-60min,P<0.05)、(0.56±0.09)(髓质,RAS-60min,P<0.05)。结论:本研究验证了MEGSE序列可以无创、定量测量肾缺血状态下的OEF改变,为将来进一步应用于人类肾脏氧摄取分数的测量奠定了基础。Objective：To demonstrate the feasibility of 2D multi-echo gradient and spin echo （MEGSE） sequence used for non-invasive quantitative measurements of intrarenal oxygen extraction fraction （OEF） in rabbits with unilateral renal artery stenosis （RAS）. Methods：Fifteen New Zealand rabbits with a mean weight of 3.2kg were used in this study. Unilateral partial ligation of left renal artery was performed to create the animal model of acute RAS. Three sequential MEGSE scans were performed pre-RAS operation （baseline： tpl）,30min post-RAS operation （tp2） and 60min post-RAS operation （tp3） respectively,to acquire the OEF before and after the renal artery stenosis. Results： Significant increments of OEF in the renal cortex and medulla were obtained （Cortex, OEF= 0.36 ＋ 0.08 at baseline vs 0.46 ± 0. 14 at post-RAS 30min,0. 46±0. 13 at post-RAS 60min, P〈0.05; Medulla, OEF= 0. 39 ±0. 11 at baseline vs0. 51 ± O. 12 at post-RAS 30rain, 0.56±0.09 at post-RAS 60min, P〈0.05）, suggesting an increase of oxygen consumption in the cortex and medulla region after the renal artery stenosis. Conclusion：Our results demonstrate a consistent and significant increase of renal OEF in rabbits post renal artery stenosis,suggesting that MEGSE technique can be utilized to noninvasively detect pathophysiological changes in intrarenal OEF during an reduction of renal blood flow, which may be potentially applicable in humans in the future.

关 键 词：氧摄取分数 肾动脉狭窄 磁共振成像 

分 类 号：R692[医药卫生—泌尿科学] R-332[医药卫生—外科学] R445.2[医药卫生—临床医学]