Department of Medical Imaging, Jinling Hospital, School of Medicine, Nanjing University, Nanjing 210002, China.
Department of National Clinical Research Center of Kidney Diseases, Jinling Hospital, School of Medicine, Nanjing University, Nanjing 210002, China.
Korean J Radiol. 2018 Mar-Apr;19(2):201-208. doi: 10.3348/kjr.2018.19.2.201. Epub 2018 Feb 22.
To determine the feasibility of reduced field-of-view diffusion-weighted imaging (rFOV DWI) with multi-b values to detect functional variability in transplanted kidneys.
Using a 3T MRI scanner, multi-b rFOV DWI of transplanted kidney or native kidney was performed in 40 renal transplantation recipients and 18 healthy volunteers. The patients were stratified, according to an estimated glomerular filtration rate (eGFR): Group 1, eGFR ≥ 60 mL/min/1.73 m; Group 2, eGFR ≥ 30 mL/min/1.73 m and < 60 mL/min/1.73 m; Group 3, eGFR < 30 mL/min/1.73 m. Total apparent diffusion coefficient (ADC), perfusion-free ADC (ADC) and perfusion fraction (F) of kidneys were calculated and compared among the four groups. Correlations between the imaging results and eGFR were assessed.
All volunteers had eGFR ≥ 60 mL/min/1.73 m, while 16, 16, and 8 patients were included in Groups 1, 2, and 3, respectively. In the renal cortex, ADCT was higher in Group 1 ([1.65 ± 0.13] × 10 mm/s) than Group 3 ([1.44 ± 0.11] × 10 mm/s) ( < 0.05), and the inter-group differences of F values were significant (all < 0.05) (0.330 ± 0.024, 0.309 ± 0.019, 0.278 ± 0.033, and 0.250 ± 0.028 for control group, Groups 1, 2, and 3, respectively). Renal cortical ADC, ADC, F, and renal medullary ADC and F correlated positively with eGFR ( = 0.596, 0.403, 0.711, 0.341, and 0.323, respectively; all < 0.05). When using 0.278 as the cutoff value, renal cortical F had a sensitivity of 97.1% and a specificity of 66.7% for predicting decreased renal function.
Multi-b rFOV DWI presents transplanted kidneys with high resolution, which is a promising functional tool for non-invasively monitoring function of transplanted kidneys.
确定使用多 b 值减少视野弥散加权成像（rFOV DWI）检测移植肾功能变异性的可行性。
使用 3T MRI 扫描仪对 40 例肾移植受者和 18 例健康志愿者的移植肾或正常肾进行多 b 值 rFOV DWI。根据估算肾小球滤过率（eGFR）对患者进行分层：组 1，eGFR≥60mL/min/1.73m2；组 2，eGFR≥30mL/min/1.73m2 且＜60mL/min/1.73m2；组 3，eGFR＜30mL/min/1.73m2。计算并比较各组肾脏的总表观弥散系数（ADC）、无灌注 ADC（ADC）和灌注分数（F）。评估成像结果与 eGFR 的相关性。
所有志愿者的 eGFR≥60mL/min/1.73m2，而组 1、组 2 和组 3 分别纳入 16、16 和 8 例患者。在肾皮质中，组 1 的 ADCT[1.65±0.13]×10mm/s 高于组 3[1.44±0.11]×10mm/s（<0.05），各组间 F 值的差异具有统计学意义（均<0.05）（对照组、组 1、组 2 和组 3 的 F 值分别为 0.330±0.024、0.309±0.019、0.278±0.033 和 0.250±0.028）。肾皮质 ADC、ADC、F 值与 eGFR 呈正相关（=0.596、0.403、0.711、0.341 和 0.323，均<0.05）。当使用 0.278 作为截断值时，肾皮质 F 值预测肾功能下降的敏感性为 97.1%，特异性为 66.7%。
多 b 值 rFOV DWI 可提供高分辨率的移植肾图像，有望成为一种非侵入性监测移植肾功能的功能性工具。
