定量CT测定骨矿物含量的双能量方法

骨质疏松症最早显示在椎骨小梁骨的变化上。用定量ＣＴ测量椎骨小梁骨矿物质含量，可对该病进行早期诊断。双能量方法可分离出脂肪影响。提高测试精度。对两种双能量方法定量地分析了它们的系统误差和随机误差，并与单能量方法的误差对照。完成了２０个临床病例的试验。单能量ＣＴ系统误差较大，双能量ＣＴ随机误差较大，但若ＣＴ机的测试误差控制在正常范围内，则双能量ＣＴ的总误差明显地小于单能量ＣＴ的总误差。故认为双能量方法

DUAL-ENERGY METHOD FOR QUANTITATIVE CT DETERMINATION OF BONE MINERAL CONTENTS

An accurate and practical method is required for early diagnosis of osteoporosis. The initial osteoporosis was found as a change of trabeculae of lumbar vertebrae. Quantitative CT(QCT)determination was convenient to be used in this area. Using dual-energy method, we could minimize the error due to the effect of fat. In this paper, after briefly introducing the QCT method of single and dual-energy (SECT and DECT), the system and random error were analysed and compared quantitatively. Besides, clinnical experiments were made in 20 cases using dual-energy method. The system error of SECT was higher than DECT, while the random crror of DECT was higher than SECT. By considering the total error, the DECT was clearly more superior if the H/H of CT machine was well controlled (such as 0.35% for GE-9800).So, it is expected to obtain better effect in the early diagnosis of osteoporosis by DECT and also in the monitoring of cure effect by SECT.