Savelli Sara, Di Maurizio Marco, Perrone Anna, Tesei Jacopo, Francioso Antonella, Angeletti Marco, La Barbera Laura, Ballesio Laura, de Felice Carlo, Porfiri Lucio Maria, Manganaro Lucia
UMBERTO I hospital-LA SAPIENZA University of Rome, Radiological Sciences, Italy.
Prenat Diagn. 2007 Dec;27(12):1104-11. doi: 10.1002/pd.1839.
To investigate apparent diffusion coefficient (ADC) mapping with the measurement of renal tissue ADC value of normal and pathological fetal kidneys at various gestational ages (GAs).
Fifty pregnant women underwent magnetic resonance images (MRI) after ultrasound (US) for suspected fetal genitourinary disorders (16) or for suspected disorders in other organs (34). A multiplanar study of urinary system was obtained by using conventional T2-weighted sequences and echo planar imaging (EPI); Diffusion-weighted images and ADC maps were evaluated. The renal tissue ADC value was measured for all normal and abnormal fetuses and related to GA.
MRI confirmed urinary anomalies in 15 fetuses [2 renal developmental variants, 2 nephropathies, 4 multicystic dysplastic kidneys (MCDK), 7 renal tract dilatations] and detected normal kidneys in the remaining 35 fetuses. Normal renal parenchyma showed bright signal on diffusion-weighted images with ADC values ranging from 1,065 to 1,327 microm(2)/s with a tendency to decrease over GA. A pathological ADC was detected in cases of bilateral MCDK, huge dilatations and in cases of nephropathies.
Diffusion-weighted imaging (DWI) with ADC mapping can be used in the evaluation of fetal renal parenchyma and may become a tool of assessing function of the fetal kidney by means of measurement of renal tissue ADC values.
通过测量不同孕周（GA）正常和病理状态下胎儿肾脏的表观扩散系数（ADC）值，研究ADC成像。
50例孕妇在超声（US）检查后因怀疑胎儿泌尿生殖系统疾病（16例）或其他器官疾病（34例）接受了磁共振成像（MRI）检查。采用常规T2加权序列和回波平面成像（EPI）对泌尿系统进行多平面研究；评估扩散加权图像和ADC图。测量所有正常和异常胎儿的肾组织ADC值，并与孕周相关联。
MRI证实15例胎儿存在泌尿系统异常[2例肾脏发育变异、2例肾病、4例多囊性发育不良肾（MCDK）、7例肾盏扩张]，其余35例胎儿肾脏正常。正常肾实质在扩散加权图像上表现为高信号，ADC值范围为1065至1327μm²/s，且有随孕周增加而降低的趋势。在双侧MCDK、巨大扩张和肾病病例中检测到病理性ADC。
具有ADC成像的扩散加权成像（DWI）可用于评估胎儿肾实质，并且可能通过测量肾组织ADC值成为评估胎儿肾功能的一种工具。
