Institute of Clinical Radiology and Nuclear Medicine, University Medical Center Mannheim, University of Heidelberg, Heidelberg, Germany.
Kidney Int. 2012 Apr;81(7):684-9. doi: 10.1038/ki.2011.455. Epub 2012 Jan 11.
Renal blood oxygen level-dependent magnetic resonance imaging (BOLD-MRI) is a noninvasive fast technique to characterize renal function. Here we evaluated the impact of renal function on the relaxation rate (R2()) in the cortex and medulla to provide baseline data for further use of renal BOLD-MRI. This parameter was evaluated in 400 patients scheduled for abdominal imaging who underwent transversal blood oxygen level-dependent measurements with a multi-echo gradient-echo sequence with 12 echo times. The loss of phase coherence (T2()) maps were generated in which kidney regions of interest were selected to differentiate the medulla and cortex, and R2() was equated to 1/T2(). Individual R2() values were, in turn, correlated to the eGFR (MDRD formula of 280 patients with available serum creatinine measurements), age, and gender each for 1.5 and 3.0 T field-strength scans of 342 patients. At both the field strengths, no significant differences in R2() of the cortex and medulla were found between patient gender, age, eGFR, or between different stages of chronic kidney disease determined using the KDOQI system. Thus, BOLD-MRI of a non-specific patient population failed to discriminate between the patients with various stages of chronic kidney disease.
肾脏血氧水平依赖磁共振成像（BOLD-MRI）是一种非侵入性的快速技术，可用于描述肾功能。在这里，我们评估了肾功能对皮质和髓质弛豫率（R2(））的影响，为进一步使用肾脏 BOLD-MRI 提供了基线数据。该参数在 400 名接受腹部成像的患者中进行了评估，这些患者接受了多回波梯度回波序列的横断面血氧水平依赖测量，该序列具有 12 个回波时间。生成了相位相干性丧失（T2(））图，其中选择了肾脏感兴趣区域以区分髓质和皮质，并将 R2() 等同于 1/T2(）。依次将个体 R2() 值与 eGFR（280 名具有可用血清肌酐测量值的 MDRD 公式）、年龄和性别相关联，对于 342 名患者的 1.5 和 3.0 T 场强扫描。在两种场强下，患者性别、年龄、eGFR 或使用 KDOQI 系统确定的慢性肾脏病不同阶段之间，皮质和髓质的 R2() 均无显著差异。因此，对非特定患者人群进行 BOLD-MRI 无法区分慢性肾脏病不同阶段的患者。
