Bartlett E J, Brodie J D, Wolf A P, Christman D R, Laska E, Meissner M
Department of Psychiatry, NYU Medical Center, NY 10016.
J Cereb Blood Flow Metab. 1988 Aug;8(4):502-12. doi: 10.1038/jcbfm.1988.91.
Positron emission tomography with 11C-2-deoxyglucose was used to determine the test-retest variability of regional cerebral glucose metabolism in 22 young normal right-handed men scanned twice in a 24-h period under baseline (resting) conditions. To assess the effects of scan order and time of day on variability, 12 subjects were scanned in the morning and afternoon of the same day (a.m.-p.m.) and 10 in the reverse order (p.m.-a.m.) with a night in between. The effect of anxiety on metabolism was also assessed. Seventy-three percent of the total subject group showed changes in whole brain metabolism from the first to the second measurement of 10% or less, with comparable changes in various cortical and subcortical regions. When a scaling factor was used to equate the whole brain metabolism in the two scans for each individual, the resulting average regional changes for each group were no more than 1%. This suggests that the proportion of the whole brain metabolism utilized regionally is stable in a group of subjects over time. Both groups of subjects had lower morning than afternoon metabolism, but the differences were slight in the p.m.-a.m. group. One measure of anxiety (pulse at run 1) was correlated with run 1 metabolism and with the percentage of change from run 1 to run 2. No significant run 2 correlations were observed. This is the first study to measure test-retest variability in cerebral glucose metabolism in a large sample of young normal subjects. It demonstrates that the deoxyglucose method yields low intrasubject variability and high stability over a 24-h period.
采用11C-2-脱氧葡萄糖正电子发射断层扫描技术，对22名年轻的正常右利手男性在基线（静息）状态下于24小时内进行两次扫描，以确定局部脑葡萄糖代谢的重测变异性。为评估扫描顺序和一天中的时间对变异性的影响，12名受试者在同一天的上午和下午进行扫描（上午-下午），10名受试者以相反顺序（下午-上午）进行扫描，中间间隔一晚。还评估了焦虑对代谢的影响。在整个受试者组中，73%的人从第一次测量到第二次测量时全脑代谢变化在10%或以下，不同皮质和皮质下区域的变化相当。当使用缩放因子使每个个体的两次扫描中的全脑代谢相等时，每组的平均局部变化不超过1%。这表明在一组受试者中，局部利用的全脑代谢比例随时间是稳定的。两组受试者上午的代谢均低于下午，但下午-上午组的差异较小。一种焦虑测量指标（第一次扫描时的脉搏）与第一次扫描时的代谢以及从第一次扫描到第二次扫描的变化百分比相关。未观察到与第二次扫描的显著相关性。这是第一项在大量年轻正常受试者样本中测量脑葡萄糖代谢重测变异性的研究。它表明脱氧葡萄糖法在24小时内产生的受试者内变异性较低且稳定性较高。
