摘要
目的 了解扇形束 (HologicQDR 450 0A)和笔形束 (LunarDPX IQ)DXA骨密度仪测量结果之间的关系 ,探讨两者的数据换算关系。方法 1 6个骨块模型分别在HologicQDR 450 0A型和Lu narDPX IQ型DEXA仪上测量 3次 ,比较两者的灵敏度。选取其中 3个骨块模型连续测量 2 0次求变异系数 ,比较两仪器的批内精密度。每天测 5次连续 2 0d求变异系数 ,比较两仪器的批间精密度。人体腰椎骨块模型每天测 5次连续 8d,建立两仪器之间数据换算关系。结果 (1 )LunarDPX IQ型DEXA仪的灵敏度高于HologicQDR 450 0A型DEXA仪。 (2 )用小动物软件测量BA、BMC、BMD ,HologicDEXA仪的批内精密度分别为 0 57%、0 8%、1 1 % ;LunarDPX IQ型DEXA仪分别为 2 2 %、1 0 0 %、1 0 4%。HologicDEXA仪的批间精密度分别为 1 2 %、2 8%、2 4% ;LunarDPX IQ型DEXA仪分别为2 0 %、1 0 3 %、1 0 5 %。结果均显示HologicDEXA仪的精密度高于LunarDEXA仪。 (3)两仪器之间的BA、BMC、BMD绝对值差异明显 (P <0 0 5) ,但可用线性回归方程进行数据换算 :①BMD :Hologic值 =0 80 2×Lunar值 +0 31 8(r=0 991 ;P <0 0 0 1 ;SEE =0 0 3g/cm2 ) ;②BMC :Hologic值 =1 2 0×Lunar值 +1 685(r=0 984;P <0 0 0 1 ;SEE =0 81 6g) ;
Objective To compare the differences in BA, BMC and BMD estimated with fan beam X ray densitometer (Hologic QDR 4500A) and pencil beam system (Lunar DPX IQ), and to establish the transcalibrating equations between them Methods Bone area (BA), bone mineral content (BMC) and bone mineral density (BMD) of 16 small bone models and an anthropomorphic lumbar spine model were measured with two types of dual energy X ray absorptiometers (Hologic QDR 4500A and Lunar DPX IQ) Results (1) The sensitivity of Hologic QDR 4500A was lower than that of Lunar DPX IQ (2) For small bone models, the intrabatch precision of BA, BMC and BMD were 0 57%,0 8% and 1 1%,respectively, for Hologic QDR 4500A; and ,2 0%,10 0% and 10 4%, respectively, for Lunar DPX IQ The interbatch precision of BA, BMC and BMD were 1 2%, 2 8% and 2 4%, respectively, for Hologic QDR 4500A, and 2 0%,10 3% and 10 5%,respectively, for Lunar DPX IQ, suggesting that the precision of Hologic QDR 4500A was higher than that of Lunar DPX IQ (3)There were significant differences( P <0 05)and positive correlation between the results obtained with the two instruments, and interconversion factors were calculated Conversions of values based on these regression equations are: ①BMD:Hologic=0 802×Lunar+0 318( r=0 991;P <0 001;SEE=0 03 g/cm 2);②BMC:Hologic=1 20×Lunar+1 685( r=0 984; P <0 001;SEE=0 816 g); ③BA:Hologic=1 414×Lunar 1 647( r=0 972; P <0 001;SEE=0 520 cm 2) Conclusion There are differences in sensitivity, precision and absolute values between Hologic QDR 4500A and Lunar DPX IQ dual energy X ray absorptiometers (DEXA) Value conversion based on these regression equations should be used for comparing data from one laboratory to another
出处
《中国骨质疏松杂志》
CAS
CSCD
2003年第3期205-210,共6页
Chinese Journal of Osteoporosis
基金
十五"国家医学科技攻关课题 ( 2 0 0 1BA70 2B0 3)
