DWI Research Of Different Age Groups Normal Kidney

Objectives: The paper aims to measure the ADC values of renal cortex andmedulla among different age groups of volunteers by means of magneticresonance diffusion weighted imaging, observing weather there are differencesin the ADC values of renal cortex and medulla among different age groups aswell as among the same age groups.Methodology: Have the kidney magnetic resonance imaging scanning on120kidneys of60healthy volunteers from May to January in2010. And thesubjects are divided into three age groups, namely, the young group less than45years old, the middle-aged group between45t060years old, and the oldgroup more than60years old. The average age of the young group is32.3, themiddle-aged group is49.6and the old group is63.5.Use GE1.5T Signa Twin Speed magnetic resonance scanner, Tor so PAphased array coil and SE-EPI sequence. Bilateral renal coronal T1WI imagingare as follows: TR180.0ms, TE2ms,8mm in thickness,1mm in layer spacing,(NEX)2times of collection, FOV cm32cm x24cm and128x128in matrix;bilateral renal coronal DWI imaging are as follows: TR3000ms, TE57.1MS,8mm in thickness,1mm in layer spacing,(NEX)2times of collection, FOVcm32cm x24cm and128x128in matrix, the value of b is600s/mm~2、1000s/mm~22,and scanning time is17s,34S.Do the post processing on DWI images by using the software at theworkstation. Adjust threshold by the standard of the entire kidney, and that ofexcluding the renal sinus and the fat and fiber structure around the kidneys,select the b value of image processing, and automatically generate the ADCimages at the workstation. Select the T1weighted images to fuse with the ADCcorresponding images, and get new fused images, and choose the largestdimension to measure the ADC values. Then deal with the data by adopting SPSS17.0statistical software, including inferring statistically the data andexamining the t inspection and single effect analysis of variance on technicalinformation. If the P value is less than or equals to0.05, the tested differenceswill be considered to be statistically significant.Results：The results showed that when the b value is600s/mm~2, there existdifferences in renal cortex and medulla among the young group, themiddle-aged group and the old group. The ADC values of renal cortex andmedulla of the young groups are higher that those of the old group, P <0.05,which are statistically significant; the ADC values of renal cortex and medullaof the middle-aged group are higher than those of the old group, P＜0.05,which are statistically significant; the ADC values of renal cortex and medullaof the middle-aged group are higher than those of the young group, P>0.05,which are not statistically significant. When the value of b is1000s/mm~2, thereare remarkable differences in renal cortex among the three groups. The ADCvalues of the young group and the middle-aged group are higher that of theolder age group, P <0.05, which are statistically significant; there are noremarkable differences in the ADC values of renal cortex and medulla betweenthe young group and the old group, P＞0.05，which are not statisticallysignificant. There are no remarkable differences in the ADC values of medullaamong the three groups, P>0.05, which are not statistically significant.There exist no significant differences in the renal cortex and medullaamong the three groups, whether the b value is600s/mm~2or1000s/mm~2not,which are not statistically significant.Conclusion:1. The DWI can be adopted to observe the physiological changes of normalkidney.2. When the b value is600s/mm~2, there are differences in the ADC values of both the renal cortex and the medulla among the young group, themiddle-aged and the old group,which are statistically significant. When the bvalue is1000s/mm~2, there are differences in the ADC value of the renal cortexamong the three groups, which are statistically significant.