泌尿系水成像技术参数优化的基础研究

目的：通过调控技术参数进行图像质量的定量分析，达到技术参数优化的目的。方法：对20例健康志愿者分别采用TR=8000ms、TE=250ms和TR：6000ms、TE=150ms两种不同的参数扫描，测量感兴趣区信号的平均值及感兴趣区信号平均值的标准差。计算出上尿路内尿液、肾实质及周围背景组织信噪比，上尿路内尿液与肾实质、上尿路内尿液与周围背景组织及肾实质与周围背景组织对比度和对比噪声比，其计算结果运用配对t检验进行统计分析。结果：图像质量控制指标即组织的信号强度、信噪比、对比度和对比噪声比定量分析结果表明TR=6000ms、TE=150ms优于TR=8000ms、TE=250ms。结论：应用软件为GE5．4．2的GESigna 0．5T超导型扫描机，泌尿系水成像最佳的TR为6000ms，TE为150ms。

Basic study on optimization of technique parameter for magnetic resonance urography

Objective:To optimize technique parameters by adjusting technique parameter and analyzing quantitatively image quality. Methods:Mean signal strength and standard deviation in region of interest were measured in 20 healthy volunteers by using scanning of two different parameters: TR=6000 ms,TE=150 ms and TR=8000 ms,TE=250 ms. Signal-to-noise ratio (SNR) of water in upper urinary tract, renal parenchyma and surrounding background tissue were calculated. Contrast(C) and contrast-to-noise ratio (C/N or CNR) of water in upper urinary tract with renal parenchyma, water in upper urinary tract with surrounding background tissue and renal parenchyma with surrounding background tissue were calculated also. The calculation results were taken statistical analysis. Results:The result of quantitative analysis in image quality control index (signal strength, SNR, C, C/N) demonstrated that technique parameter TR=6000 ms,TE=150 ms was better than the TR=8000 ms,TE=250 ms. Conclusion:TR=6000 ms,TE=150 ms was the best technique parameter in magnetic resonance urography for scanner of GE Signa 0.5T with application software GE 5.4.2.