分形维数在CT腰椎松质骨图像中应用的研究  

Study on the application of fractal dimension in CT lumbar vertebral cancellous bone images

作　　者：冯银波[1] 方向明[1] 陈宏伟[1] 张丽娟[1] 

机构地区：[1]南京医科大学附属无锡人民医院医学影像科,江苏无锡214023

出　　处：《同济大学学报（医学版）》2016年第3期107-111,共5页Journal of Tongji University(Medical Science)

基　　金：国家自然科学基金面上项目(81271629)

摘　　要：目的探讨分形维数（fractal dimension,FD）在腰椎CT中对松质骨微结构量化的应用价值。方法回顾性分析2012年12月至2015年9月,因腰痛来本院就诊并行腰椎CT检查的中青年男性患者115例,分为两组：A组,28～31岁,61例;B组,38～41岁,54例。入组者均无腰椎退行性变,使用imagej分析腰4椎体松质骨区域图像,量化灰度纹理特征。检验FD值在两组间的差异并行ROC曲线分析。结果 A组腰椎松质骨的FD值为1.463±0.056,B组腰椎松质骨的FD值为1.418±0.038,两组间的差异有统计学意义（P=0.001）。经ROC曲线分析,判断FD最佳临近点为1.423,此时诊断的灵敏度为75.4%,特异度为55.6%。结论采用分形维数分析腰椎松质骨CT图像,提取灰度纹理信息,可量化一定轻微退变程度的骨微结构。Objective To assess the application of fractal dimension（FD） calculated from CT images in evaluation of cancellous bone texture of lumbar vertebrae.Methods One hundred and fifteen males aged 28-41 years with history of back pain were examined with computed tomography.The FD value of 4th lumbar vertebra（L4） was calculated from CT images with box-counting method to determine its characteristic spongy network.Results The FD value in youth group（38-31 years）and middle-age group（38-41 years） was 1.463 ± 0.056 and 1.418 ± 0.038,respectively（P =0.001）.Taking the cut-off value of 1.423 in receiver operator characteristic curve（ROC） the sensitivity and specificity of FD in diagnosis of osteoporosis was 75.4% and 55.6%,respectively.Conclusion The results suggest that the application of fractal analysis of CT images can provide valuable information on the trabecular pattern of vertebrae.

关 键 词：骨质疏松症 CT 分形维数 

分 类 号：R816[医药卫生—放射医学]