摘要
目的:观察不同测量者用不同大小的兴趣区测量正常人脑组织不同解剖部位的平均表观弥散系数(ADC)值是否存在差异。方法:60例MR检查正常的健康自愿者行弥散加权成像。两个测量者分别用两个兴趣区犤(15±3)mm2和(35±4)mm2犦在ADC图上测量脑内不同解剖部位(半卵圆中心、额叶白质、尾状核头、壳核、丘脑、胼胝体膝、胼胝体压部、内囊后肢、桥脑及侧脑室体部)的ADC值。结果:脑实质的平均ADC值范围为(0.668±0.06)×10-3～(0.803±0.02)×10-3mm2s,侧脑室体部的平均ADC值为(2.968±0.05)×10-3mm2s。不同测量者之间在半卵圆中心、额叶白质、胼胝体膝、内囊后肢、桥脑测得的ADC值有显著性差异,对胼胝体膝、内囊后肢、桥脑不同兴趣区的ADC值测量有显著性差异。结论:由于不同测量者和不同兴趣区对脑内一些结构的ADC值测量的差异性,对脑内某些区域用ADC值评价病理改变并不可靠。
Objective： To test the difference of region of interest（ROI） size and interobserver on the measuring of apparent diffusion coefficient value of normal human brain. Methods： Sixty volunteers with normal MR findings underwent diffusionweighted imaging. Two radiologists independently placed two ROI areas of （15±3）mm^2 and （35±4）mm^2（former areas inside the latter areas） at different sites of the hrain（centrum semiovale, frontal white matter, nucleus caudatus, putamen, thalamus, corpus callosum, posterior limb of internal capsnle, pons and body of lateral ventricles） from trace images. Results： Mean ADC values of parenchymal areas of brain ranged between （0.668±0.06）×10^-3-（0.803±0.02）×10^-3mm^2/s. Mean ADC values of the body of lateral ventricles was （2.968±0.05）×10^-3mm^2/s. lnlerobserver variance was significant in some of the specified areas（centrum semiovale, frontal white matter, corpus callosum, posterior limh of internal capsule and pons）. Varying ROI sizes at the corpus callosum, posterior limb of internal capsule, and pons yielded statistically different ADC values. Conclusion： ADC values are found to be unreliable for use in assessing brain disease in some specific areas of the brain owing to interobserver variance and different ROI sizes.
出处
《中国临床医学影像杂志》
CAS
北大核心
2005年第9期481-483,共3页
Journal of China Clinic Medical Imaging
关键词
脑
磁共振成像
弥散
brain
diffusion magnetic resonance imaging
