The Goldyne Savad Institute of Gene Therapy, Hadassah Hebrew University Medical Center, Jerusalem, Israel.
Nephrol Dial Transplant. 2013 May;28(5):1150-6. doi: 10.1093/ndt/gfs541. Epub 2013 Jan 4.
The clinical use of iodinated radiocontrast agents or gadolinium for renal perfusion imaging is limited in the presence of renal dysfunction. We have previously demonstrated the feasibility of hemodynamic response imaging (HRI), a functional magnetic resonance imaging (MRI) method combined with hypercapnia and hypercapnic-hyperoxia, for monitoring changes in liver perfusion and hemodynamics. The aim of the present study was to evaluate the utility of HRI for monitoring changes in renal perfusion and hemodynamics.
Renal HRI maps were acquired during graded hypercapnia (95% air + 5% CO2) and hypercapnic-hyperoxia (95% O2 + 5% CO2) in control mice. The utility of HRI for monitoring changes in renal perfusion and oxygenation was evaluated using pharmacological inhibition of nitric oxide synthase and cycloxygenase as well as in rhabdomyolysis-induced acute kidney injury (AKI) in mice. HRI results were further interpreted using Doppler ultrasound (US).
Renal HRI maps revealed pronounced signal-intensity changes in response to both hypercapnia and hypercapnic-hyperoxia, reflecting intense vascular reactivity. These changes were significantly attenuated following the pharmacological intervention and during AKI, corresponding with hampered perfusion dynamics, as confirmed by Doppler US.
The applicability of the non-invasive HRI method suggests its potential use for the evaluation of renal perfusion and vascular reactivity, excluding the need for contrast-agent administration.
在肾功能不全的情况下，临床使用碘造影剂或钆进行肾灌注成像受到限制。我们之前已经证明了血流动力学反应成像（HRI）的可行性，这是一种结合高碳酸血症和高碳酸血症-高氧的磁共振成像（MRI）方法，可用于监测肝灌注和血液动力学的变化。本研究的目的是评估 HRI 在监测肾灌注和血液动力学变化中的应用。
在对照小鼠中，在逐渐升高的高碳酸血症（95%空气+5% CO2）和高碳酸血症-高氧（95% O2+5% CO2）期间采集肾 HRI 图。使用一氧化氮合酶和环氧化酶的药理学抑制以及肌红蛋白尿诱导的急性肾损伤（AKI）来评估 HRI 监测肾灌注和氧合变化的效用。使用多普勒超声（US）进一步解释 HRI 结果。
肾 HRI 图显示出对高碳酸血症和高碳酸血症-高氧的强烈信号强度变化，反映了强烈的血管反应性。这些变化在药理学干预后和 AKI 期间明显减弱，与灌注动力学受阻相对应，这与多普勒 US 确认的情况一致。
非侵入性 HRI 方法的适用性表明其可能用于评估肾灌注和血管反应性，无需使用造影剂。
