摘要
目的：探讨肾脏及本底兴趣区ROI的勾画方式对Gates法测定肾小球滤过率（GFR）的影响。方法：对41例患者行肾动态显像，并按不同ROI勾画法计算GFR。改变本底ROI位置、大小、本底与肾脏ROI距离及肾脏ROI大小、局部偏离，观察GFR变化；将各GFR与标准Gates法GFR比较，观察结果偏离程度及导致结果偏离的因素。结果：①logistic多因素分析表明，本底ROI位置、大小、本底与肾脏ROI间距离以及“肾脏ROI大小、局部偏离”均是影响GFR的重要因素（x^2分别为250．9，73．9，53．5，215．8，P=0．000）；②本底位于肾脏正下方较大范围内或肾脏ROI在外下方局部外偏时GFR与标准Gates法十分接近；本底ROI、肾脏ROI的其它各种改变均可对GFR产生较大程度的影响。结论：①Gates法GFR测定时，ROI勾画须注意多种影响因素的作用。②本底ROI设置于肾脏正下方（20～160）象素大小、（0～16）象素距离范围内可减少本底大小、距离对GFR影响。
Objective：To investigate the influence of different kidney and background region of interest （ROI） extraction methods to the measurement of glomerular filtration rate （GFR） in Gates＇method. Methods： Dynamic renal imaging was performed in forty-one patients; GFR was obtained using different ROI extraction met, hods. After changing the position, size of background ROI, the distance between background ROI and kidney ROI, the magnitude and local deviation of kidney ROI, the variation of GFR were studied. Each of the GFR variation was compared with standardized GFR in Gates＇ method, to learn the degree of variation and factors leading to these variations. Results： （1） Study by logistic regression, it was demonstrated that the position and size of background ROI,distance between background ROI and that of kidney, magnitude and local deviation of kidney ROt were all important factors in influencing GFR （x^2 was 250.9,73.9,53.5,215.8 respectively, P：0. 000）. （2）Measured GFR was very much similar to the standardized one in Gates＇ method when background ROI was put just beneath the kidney in a large dimension or the kidney ROI was deviated to the outer-inferior direction. A relative obvious influence was showed in the other changes of background ROI and kidney ROI. Conclusion：（1） Various factors must be considered when ROI is extracted in Gates＇ method;（2） The influence of the size,distance of back ground ROI can be reduced by drawing background ROI just beneath the kidney in a pixel size of 20-160 and in a pixel distance of 0-16.
出处
《放射学实践》
2007年第1期92-95,共4页
Radiologic Practice
