Stamatelatos I E, Dilmanian F A, Ma R, Lidofsky L J, Weber D A, Pierson R N, Kamen Y, Yasumura S
Medical Department, Brookhaven National Laboratory, Upton, NY 11973.
Phys Med Biol. 1993 May;38(5):615-26. doi: 10.1088/0031-9155/38/5/004.
A description is given of the calibration and performance of the upgraded facility at Brookhaven National Laboratory (BNL) for measuring total body nitrogen using the technique of prompt gamma neutron activation analysis. With the improved calibration, total body nitrogen can be more accurately measured not only in normal subjects but also in obese and wasted patients. Body hydrogen is used as an internal standard. We examined the effect of a heavy-water premoderator on the uniformity of composite sensitivity, nitrogen and hydrogen measurement statistics, and dose to the subject. The calibration technique corrects the ratio of nitrogen-to-hydrogen counts measured from the subject for body size. Additionally, a correction for subcutaneous adipose tissue on the nitrogen-to-hydrogen count ratio is introduced. The newly upgraded BNL facility provides precision in counting statistics using a Remcal anthropomorphic phantom filled with a tissue-equivalent solution of 2.1% for a body dose of 0.35 mSv using a 2.5 cm D2O premoderator. The measurements were made at five 20 cm sections, counting for 200 s per section.
介绍了布鲁克海文国家实验室（BNL）升级后的全身氮测量设施的校准和性能，该设施采用瞬发伽马中子活化分析技术。通过改进校准，不仅可以更准确地测量正常受试者的全身氮含量，还能测量肥胖和消瘦患者的全身氮含量。以体内氢作为内标。我们研究了重水慢化剂对复合灵敏度均匀性、氮和氢测量统计数据以及受试者剂量的影响。校准技术根据受试者的体型校正从受试者测量得到的氮与氢计数的比值。此外，还引入了对皮下脂肪组织对氮氢计数比影响的校正。新升级的BNL设施使用填充了2.1%组织等效溶液的Remcal人体模型，在使用2.5厘米重水慢化剂且人体剂量为0.35毫希沃特的情况下，在计数统计方面具有高精度。测量在五个20厘米的截面进行，每个截面计数200秒。
