Diffusion tensor imaging of renal ischemia reperfusion injury in an experimental model
Diffusion tensor imaging of renal ischemia reperfusion injury in an experimental model
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DOI：
10.1002/nbm.1486
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发表时间：
2010-06-01
影响因子：
2.9
通讯作者：
Wu, Ed X.
中科院分区：
文献类型：
--
作者：
Cheung, Jerry S.;Fan, Shu Juan;Wu, Ed X.
肾缺血再灌注损伤（IRI）是急性肾功能衰竭的主要原因。它发生在各种临床环境中，如肾移植、休克和血管手术。血清肌酐水平可作为判断肾IRI患者肾功能损害程度的指标。然而，它仅评价整体肾功能。在这项研究中，扩散张量成像（DTI）被用来表征肾脏IRI在实验大鼠模型。对8只单侧肾IRI 60 min的SD大鼠和8只正常SD大鼠进行了b值为300 s/mm（2）、6个扩散梯度方向为71的自旋回波平面DTI。在MI急性期测量表观弥散系数（ADC）、方向弥散系数和各向异性分数（FA）。IR损伤的动物也通过扩散加权成像进行检查，其中7个b值高达1000 s/mm（2），以使用双室模型估计真实扩散系数（D-true）和灌注分数（P-fraction）。损伤肾皮质的ADC值（1.69 +/- 0.24 x 10（-3）mm（2）/s）显著低于对侧完整肾皮质的ADC值（2.03 +/- 0.35 x 10（-3）mm（2）/s）（p < 0.01）。同时，IR损伤延髓的ADC值和FA值（分别为1.37 ± 0.27 × 10（-3）mm（2）/s和0.28 ± 0.04）显著低于对侧完整延髓（分别为2.01 ± 0.38 × 10（-3）mm（2）/s和0.36 ± 0.04）（p < 0.01）。双房室模型分析显示IR损伤肾脏的D-真和P-分数降低。肾脏组织学显示皮质和髓质广泛的细胞肿胀和红细胞充血，髓质细胞坏死/凋亡和管型形成。这些实验结果表明，DTI可以探测肾脏IRI后肾脏的结构和功能信息。版权所有（C）2010约翰威利父子有限公司
Renal ischemia reperfusion injury (IRI) is a major cause of acute renal failure. It occurs in various clinical settings such as renal transplantation, shock and vascular surgery. Serum creatinine level has been used as an index for estimating the degree of renal functional loss in renal IRI. However, it only evaluates the global renal function. In this study, diffusion tensor imaging (DTI) was used to characterize renal IRI in an experimental rat model. Spin-echo echo-planar DTI with b-value of 300 s/mm(2) and 6 diffusion gradient directions was performed at 71 in 8 Sprague-Dawley (SD) with 60-min unilateral renal IRI and 8 normal SD rats. Apparent diffusion coefficient (ADC), directional diffusivities and fractional anisotropy (FA) were measured at the acute stage of MI. The IR-injured animals were also examined by diffusion-weighted imaging with 7 b-values up to 1000 s/mm(2) to estimate true diffusion coefficient (D-true) and perfusion fraction (P-fraction) using a bi-compartmental model. ADC of injured renal cortex (1.69 +/- 0.24 x 10(-3) mm(2)/s) was significantly lower (p < 0.01) than that of contralateral intact cortex (2.03 +/- 0.35 x 10(-3) mm(2)/s). Meanwhile, both ADC and FA of IR-injured medulla (1.37 +/- 0.27 X 10(-3) mm(2)/s and 0.28 +/- 0.04, respectively) were significantly less (p < 0.01) than those of contralateral intact medulla (2.01 +/- 0.38 X 10(-3) mm(2)/s and 0.36 +/- 0.04, respectively). The bi-compartmental model analysis revealed the decrease in D-true and P-fraction in the IR-injured kidneys. Kidney histology showed widespread cell swelling and erythrocyte congestion in both cortex and medulla, and cell necrosis/apoptosis and cast formation in medulla. These experimental findings demonstrated that DTI can probe both structural and functional information of kidneys following renal IRI. Copyright (C) 2010 John Wiley & Sons, Ltd.