Park Jonathan K, Rhee Thomas K, Cashen Ty A, Shin Wanyong, Resnick Scott A, Gehl James A, Schirf Brian E, Wang Dingxin, Larson Andrew C, Carroll Timothy J, Omary Reed A
Department of Radiology, Northwestern University Feinberg School of Medicine, 448 East Ontario Street, Suite 700, Chicago, IL 60611, USA.
J Vasc Interv Radiol. 2007 Nov;18(11):1409-16. doi: 10.1016/j.jvir.2007.08.002.
To prospectively test the hypothesis that magnetic resonance (MR) imaging can detect changes in renal function at the time of renal artery stent placement in a swine model of renal artery stenosis (RAS).
In this animal care and use committee-approved study, hemodynamically significant (>50%) RAS was surgically induced in six pigs. MR imaging was employed for assessment of the anatomic and physiologic changes induced by fluoroscopically guided stent placement. With MR imaging, we assessed changes in renal blood flow (RBF), extraction fraction (EF), and single-kidney glomerular filtration rate (skGFR) during the procedure. Arterial diameter stenosis before and after stent placement was assessed with x-ray digital subtraction angiography (DSA). Mean changes in functional and anatomic parameters were compared with the Wilcoxon matched-pairs test, with an alpha level of 0.05.
There was no significant change in mean RBF after stent deployment (P=.44). Mean EF increased from 0.19+/-0.08 before stent placement to 0.31+/-0.17 after stent placement (P=.16). Mean skGFR measurements were 25 mL/min+/-16 before stent placement and 41 mL/min+/-28 after stent placement (P<.05). According to x-ray DSA measurements, mean stenosis measurements were 60%+/-12% before stent placement and 24%+/-16% after stent placement (P<.02).
In swine, MR imaging can detect immediate changes in renal function after radiographically guided stent placement for unilateral RAS. This functional MR technique may have applications in the setting of hybrid MR/x-ray DSA procedure suites.
前瞻性验证磁共振成像（MR）能够在猪肾动脉狭窄（RAS）模型中肾动脉支架置入时检测肾功能变化这一假设。
在这项经动物护理和使用委员会批准的研究中，通过手术在6头猪身上诱发血流动力学显著（>50%）的RAS。采用MR成像评估在荧光透视引导下支架置入所引起的解剖和生理变化。通过MR成像，我们在操作过程中评估了肾血流量（RBF）、提取分数（EF）和单肾肾小球滤过率（skGFR）的变化。使用X线数字减影血管造影（DSA）评估支架置入前后的动脉直径狭窄情况。功能和解剖参数的平均变化采用Wilcoxon配对检验进行比较，α水平设定为0.05。
支架置入后平均RBF无显著变化（P = 0.44）。平均EF从支架置入前的0.19±0.08增加到支架置入后的0.31±0.17（P = 0.16）。平均skGFR测量值在支架置入前为25 mL/min±16，支架置入后为41 mL/min±28（P<0.05）。根据X线DSA测量，平均狭窄测量值在支架置入前为60%±12%，支架置入后为24%±16%（P<0.02）。
在猪中，MR成像能够检测在影像学引导下对单侧RAS进行支架置入后肾功能的即刻变化。这种功能性MR技术可能在MR/X线DSA混合操作室环境中有应用价值。
