正常前列腺外周带的MR测量研究

Magnetic Resonance Imaging Measure on Prostate Peripheral Zone

目的测量正常前列腺外周带宽径及T2信号强度并探讨其与年龄、体重及身高的变化关系。资料与方法选取217例无泌尿系统症状(临床表现为无尿路刺激、无排尿困难、无并发症之一)的成年男性为研究对象。按年龄段分为7组:第1组(20～29岁,n=22),第2组(30～39岁,n=29),第3组(40～49岁,n=47),第4组(50～59岁,n=45),第5组(60～69岁,n=37),第6组(70～79岁,n=22),第7组(80岁及以上,n=15)。MRI测量轴位外周带的五点及七点处宽径;测量闭孔内肌、臀肌、外周带的T2信号强度,并计算外周带的相对信号强度,即外周带分别与闭孔内肌、臀肌的比值。比较分析不同年龄段上述MR测量值的变化特点。结果正常组前列腺的外周带宽径左侧为(1.15±0.25)cm,右侧为(1.16±0.23)cm。不同年龄段前列腺的外周带左右宽径有统计学意义(P<0.000)。外周带分别与闭孔内肌及臀肌的T2信号强度比分别为4.97±1.33、2.80±0.68。结论外周带宽径随年龄的变化有先变大后减小趋势,T2信号强度随年龄增大有先增高后减低趋势,可出现局灶性信号减低。外周带左右宽径、体积及相对T2信号强度与身高、体重无明显相关关系。

Objective To measure the width and the T2 signal intensity of normal prostatic peripheral zone in different age,and to evaluate the correlation of width,T2 signal intensity with age,weight and height. Materials and Methods 217 normal male adults without any urogenital symptoms were included in our study. The subjects were divided into seven groups according to their ages ： group one （20-29 years, n = 22）, group two （ 30-39 years, n = 29） ,group three （40-49 years, n = 47 ）, group four （50-59 years, n = 45 ）, group five （ 60-69 years, n = 37 ）, group six （ 70-79 years, n = 22 ）, group seven （ 80 years and more, n = 15 ）. The width and T2 signal intensity of prostatic peripheral zone, gluteus and obturator internus were measured in MRI. The gluteus and obturator internus to the peripheral zone proportion were calculated and compared in various age groups. Results The average left width of prostatic peripheral zone is （ 1.15 ± 0.25 ） cm, the average right width is （1.16 ± 0.23 ）cm, and the average volume is （14.14 ± 4.10 ）cm^3. There were significant difference in the value of left width, the right width, and the volume in various age groups （ P 〈 0. 000 ）. The ratio of obturator internus and gluteus T2 signal intensity to prostatic peripheral zone T2 signal intensity is 4.97 ± 1.33 and 2.80 ± 0.68 respectively. T2 signal intensity of the peripheral zone increased with age and then decreased. Most of T2 signal intensity of peripheral zone were homogeneous. Conclusion The peripheral zone enlarged with age and then shrinked. T2 signal intensity of the peripheral zone increased with age and then decreased.