Hocaoglu Elif, Inci Ercan, Aydin Sibel, Cesme Dilek Hacer, Kalfazade Nadir
Department of Radiology, Bakirkoy Dr. Sadi Konuk Research and Training Hospital, Istanbul, Turkey.
Department of Radiology, Haydarpasa Numune Research and Training Hospital, Istanbul, Turkey.
Int Braz J Urol. 2015 Jan-Feb;41(1):139-46. doi: 10.1590/S1677-5538.IBJU.2015.01.19.
The aim of this study was to evaluate the capability and the reliability of diffusion-weighted imaging (DWI) in the changes of kidneys occurring after extracorporeal shock wave lithotripsy (ESWL) treatment for renal stones.
A total of 32 patients who underwent ESWL treatment for renal stone disease between June and December 2011 were enrolled in this prospective study. Color Doppler ultrasonography (CDUS) and DWI were performed before and within 24 hours after ESWL. DWI was obtained with b factors of 0, 500 and 1000 s/ mm2 at 1.5 T MRI. Each of Resistive index (RI) and ADC values were calculated from the three regions of renal upper, middle and lower zones for both of the affected and contralateral kidneys. Paired sample t test was used for statistical analyses.
After ESWL, the treated kidneys had statistically significant lower ADC values in all different regions compared with previous renal images. The best discriminative parameter was signal intensity with a b value of 1000 s/mm2. The changes of DWI after ESWL were noteworthy in the middle of the treated kidney (p < 0.01). There were no significant difference between RI values in all regions of treated and contralateral kidneys before and after treatment with ESWL (p>0.05).
DWI is a valuable technique enables the detection of changes in DWI after ESWL treatment that may provide useful information in prediction of renal damage by shock waves, even CDUS is normal.
本研究旨在评估弥散加权成像（DWI）在体外冲击波碎石术（ESWL）治疗肾结石后肾脏变化中的能力及可靠性。
本前瞻性研究纳入了2011年6月至12月间因肾结石疾病接受ESWL治疗的32例患者。在ESWL治疗前及治疗后24小时内进行彩色多普勒超声（CDUS）和DWI检查。在1.5T磁共振成像（MRI）上，分别以b值为0、500和1000s/mm²获取DWI图像。分别计算患侧和对侧肾脏上、中、下三个区域的阻力指数（RI）和表观扩散系数（ADC）值。采用配对样本t检验进行统计学分析。
ESWL治疗后，与治疗前肾脏图像相比，治疗侧肾脏在所有不同区域的ADC值均有统计学意义的降低。最佳鉴别参数是b值为1000s/mm²时的信号强度。ESWL治疗后，治疗侧肾脏中部的DWI变化值得关注（p<0.01）。ESWL治疗前后，治疗侧和对侧肾脏所有区域的RI值均无显著差异（p>0.05）。
DWI是一项有价值的技术，即使在CDUS正常的情况下，它也能检测到ESWL治疗后DWI的变化，这可能为预测冲击波对肾脏的损伤提供有用信息。
