Gropler R J, Siegel B A, Lee K J, Moerlein S M, Perry D J, Bergmann S R, Geltman E M
Division of Nuclear Medicine, Edward Mallinckrodt Institute of Radiology, St. Louis, Missouri 63110.
J Nucl Med. 1990 Nov;31(11):1749-56.
In initial studies using fluorine-18-fluorodeoxyglucose (FDG) in normal fasted subjects, we observed disparities in the regional myocardial accumulation of this tracer. Accordingly, we systematically evaluated regional myocardial FDG accumulation in comparison with regional myocardial perfusion assessed with oxygen-15-water and oxidative metabolism assessed with carbon-11-acetate in nine normal subjects (four studied after a 5-hr fast and five studied both fasted and following glucose loading). Under fasting conditions, myocardial accumulation of FDG in the septum and anterior wall averaged 80% of that in the lateral and posterior walls (p less than 0.03). In contrast, after glucose loading the regional distribution of myocardial FDG accumulation became more homogeneous. Regional myocardial perfusion, oxidative metabolism, and accumulation of carbon-11-acetate were homogeneous under both conditions. Thus, under fasting conditions there are regional variations in myocardial accumulation of FDG, which are visually apparent, are not associated with concomitant changes in oxidative metabolism or perfusion, and cannot be attributed to partial-volume effects. This significant heterogeneity may limit the specificity of PET with FDG for detecting myocardial ischemia in fasting subjects.
在最初对正常空腹受试者使用氟 - 18 - 氟脱氧葡萄糖（FDG）的研究中，我们观察到该示踪剂在心肌各区域的蓄积存在差异。因此，我们系统评估了9名正常受试者（4名在禁食5小时后进行研究，5名在禁食及葡萄糖负荷后均进行研究）心肌FDG区域蓄积情况，并与用氧 - 15 - 水评估的心肌区域灌注以及用碳 - 11 - 醋酸盐评估的氧化代谢情况进行比较。在禁食条件下，室间隔和前壁心肌FDG蓄积平均为侧壁和后壁的80%（p小于0.03）。相比之下，葡萄糖负荷后心肌FDG蓄积的区域分布变得更加均匀。在两种条件下，心肌区域灌注、氧化代谢以及碳 - 11 - 醋酸盐的蓄积都是均匀的。因此，在禁食条件下，心肌FDG蓄积存在区域差异，这些差异在视觉上很明显，与氧化代谢或灌注的伴随变化无关，也不能归因于部分容积效应。这种显著的异质性可能会限制PET使用FDG检测空腹受试者心肌缺血的特异性。
