Department of Radiology, Duke University Medical Center, Erwin Rd, Durham, NC 27710, USA.
Eur J Radiol. 2011 Nov;80(2):e1-7. doi: 10.1016/j.ejrad.2010.05.019. Epub 2010 Jun 20.
To retrospectively test the null hypotheses that the qualitative appearance of DWI and the signal intensity values in DWI and corresponding ADC values of the liver, spleen, pancreas and kidneys are identical before and after the administration of gadolinium.
Following IRB approval, DWI was acquired in 50 patients (25 male; mean age 54.9 years) prior to and after contrast administration, using single-shot echo planar imaging with b-values of 50 s/mm2 and 800 s/mm2 at 3 T. Binomial analysis was used to determine which image set was more significantly preferred in conveying the diffusion information. Pre- and post-gadolinium DWI and ADC values of corresponding regions of each organ were analyzed using standardized signal intensity measurements.
Pre-contrast DWI images of the liver, spleen, and pancreas were preferred 52%, 49%, and 58%, respectively, with none of the differences being statistically significant. DWI of the kidneys was preferred on pre-contrast images in 83% (p<0.001). In the liver and spleen, contrast caused a significant increase in the post-contrast DWI signal intensity values at b=50 (p<0.02) and b=800 (p<0.05) but had no statistically significant effect on the ADC value (p>0.40). Pancreatic DWI signal intensity and ADC values pre- and post-contrast were also not significantly different (p=0.489). In the renal parenchyma, significant decrease in the values of DWI at b=50 (p<0.01) and b=800 (p<0.01) as well as ADC (p<0.02) was demonstrated following gadolinium administration.
Intravenous gadolinium administration does not make a statistically significant difference in the qualitative appearance or ADC measurements of the liver, spleen, or pancreas when comparing pre-contrast to post-contrast DWI. In the kidneys, however, ADC values are significantly lower post-contrast with the pre-contrast diffusion weighted images also being qualitatively preferred.
回顾性检验以下两个零假设，即：肝脏、脾脏、胰腺和肾脏的 DWI 定性外观以及 DWI 中的信号强度值和相应 ADC 值在钆剂给药前后是相同的。
本研究经机构审查委员会批准，在 3T 扫描仪上使用单次激发平面回波成像采集 50 例患者（25 例男性；平均年龄 54.9 岁）的 DWI 数据，b 值分别为 50s/mm2 和 800s/mm2。采用二项式分析来确定哪组图像更能显著传递扩散信息。使用标准化信号强度测量分析各器官相应区域的钆剂给药前后 DWI 和 ADC 值。
肝脏、脾脏和胰腺的平扫 DWI 图像分别有 52%、49%和 58%被优先选择，且差异均无统计学意义。肾脏的平扫 DWI 图像有 83%（p<0.001）被优先选择。在肝脏和脾脏中，b=50（p<0.02）和 b=800（p<0.05）时，对比剂给药后 DWI 信号强度显著增加，但 ADC 值无统计学意义（p>0.40）。肝、脾的平扫和增强 DWI 信号强度及 ADC 值无显著差异（p=0.489）。在肾实质中，b=50（p<0.01）和 b=800（p<0.01）时 DWI 值以及 ADC 值（p<0.02）显著降低。
与平扫 DWI 相比，静脉注射钆剂后，肝脏、脾脏或胰腺的定性外观或 ADC 值无统计学意义的差异。然而，在肾脏中，增强后 ADC 值显著降低，且平扫扩散加权图像的定性结果也更优。
