Beddoe A H, Streat S J, Hill G L
Phys Med Biol. 1987 Feb;32(2):191-201. doi: 10.1088/0031-9155/32/2/003.
A method of measuring total body chlorine (TBCl) by prompt gamma in vivo neutron activation analysis is described which depends on the same NaI(Tl) spectra used for determinations of total body nitrogen. From these spectra counts ratios of chlorine to hydrogen are derived and TBCl is determined using a model of body composition which depends on measured body weight, total body water (by tritium dilution) and protein (6.25 X nitrogen) as well as estimated body minerals and glycogen. The precision of the method based on scanning an anthropomorphic phantom is at present only approximately 9% (SD), for a patient dose equivalent of less than 0.30 mSv. Spectra collected from 67 normal volunteers (32 male, 35 female) yielded mean values of TBCl of 72 +/- 19 (SD) g in males and 53.6 +/- 15 g in females, in broad agreement with values reported by workers using delayed gamma methods. Results are also presented for two human cadavers analysed both by neutron activation and by conventional chemical analysis; the ratios of TBCl (neutron activation) to TBCl (chemical) were 0.980 +/- 0.028 (SEM) and 0.91 +/- 0.09. Finally, it is suggested that an improvement in precision will be achieved by increasing the scanning time (thereby increasing the radiation dose equivalent) and by adding two more detectors.
描述了一种通过瞬发伽马体内中子活化分析测量全身氯（TBCl）的方法，该方法依赖于用于测定全身氮的相同碘化钠（铊）光谱。从这些光谱中得出氯与氢的计数比，并使用一种身体成分模型来确定TBCl，该模型依赖于测量的体重、全身水（通过氚稀释法）、蛋白质（6.25×氮）以及估计的身体矿物质和糖原。基于扫描人体模型的该方法的精密度目前仅约为9%（标准差），患者等效剂量小于0.30毫希沃特。从67名正常志愿者（32名男性，35名女性）收集的光谱得出，男性的TBCl平均值为72±19（标准差）克，女性为53.6±15克，这与使用缓发伽马方法的研究人员报告的值大致相符。还给出了通过中子活化分析和传统化学分析对两具人体尸体进行分析的结果；TBCl（中子活化）与TBCl（化学分析）的比值分别为0.980±0.028（标准误）和0.91±0.09。最后，建议通过增加扫描时间（从而增加等效辐射剂量）以及增加两个探测器来提高精密度。
