Quantification of Task-Specific Glucose Metabolism with Constant Infusion of 18F-FDG
Quantification of Task-Specific Glucose Metabolism with Constant Infusion of 18F-FDG
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DOI：
10.2967/jnumed.116.176156
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发表时间：
2016-12-01
影响因子：
9.3
通讯作者：
Lanzenberger, Rupert
中科院分区：
文献类型：
--
作者：
Hahn, Andreas;Gryglewski, Gregor;Lanzenberger, Rupert
研究基线和特定任务期间的大脑葡萄糖代谢率(CMRGlu)以前需要单独扫描，缺点是对象内变异性很高。我们的目标是验证一种新的方法，通过持续注入F-18-FDG，在一次测量中评估基线葡萄糖代谢和特定任务的变化。方法：15名健康受试者接受了两次正电子发射计算机断层扫描(PET)测量，并采集动脉血。作为参考，使用Patlak图(闭眼)从F-18-FDG团注后60分钟的扫描中量化基线CMRGIu。另一次扫描持续输注放射性配基95min，在此期间，受试者分别在10~20min和60~70min睁眼，35~45min和85~95min右手拇指轻拍手指。持续输液扫描分两步进行量化。首先，使用一般线性模型来拟合区域时间-活动曲线，回归变量包括基线新陈代谢、睁眼和手指敲击条件的特定任务变化以及运动参数。其次，用Patlak图对CMRGIu进行了定量。将基线回归系数乘以一般线性模型的Beta值，得到基线代谢的区域性特定的时间-活动曲线。此外，任务特定的新陈代谢变化与时间-活动曲线斜率的变化成正比，从而与CMRGIu的变化成正比。结果：来自持续输液扫描的基线CMRGIu与团注应用的基线CMRGIu相匹配(重测变异性，1.1%+/-24.7%)，而不是先前推荐的方法(变异性，-39.9%+/-25.2%，P<；0.001)。张开眼睛和敲击手指时，初级视觉皮质和运动皮质的任务特异性CMRGIu分别增加(P<；0.05，家庭误差校正)，绝对变化高达2.1Mol/100g/min和6.3%相对于基线。在睁开眼睛的情况下，默认模式区域的CMRGIu减少(P<；0.05，已纠正家庭错误)。静脉血CMRGIu定量(n=6)与动脉血CMRGIu定量结果(r>；0.99)具有很好的一致性。结论：持续输注F-18-FDG和静脉采血可一次定量测定基线葡萄糖代谢和特定任务的变化。该方法的高灵敏度和区域特异性为功能性和多模式脑成像提供了新的可能性。
The investigation of cerebral metabolic rate of glucose (CMRGlu) at baseline and during specific tasks previously required separate scans with the drawback of high intrasubject variability. We aimed to validate a novel approach to assessing baseline glucose metabolism and task-specific changes in a single measurement with a constant infusion of F-18-FDG. Methods: Fifteen healthy subjects underwent two PET measurements with arterial blood sampling. As a reference, baseline CMRGIu was quantified from a 60-min scan after F-18-FDG bolus application using the Patlak plot (eyes closed). For the other scan, a constant radioligand infusion was applied for 95 min, during which the subjects opened their eyes at 10-20 min and 60-70 min and tapped their right thumb to their fingers at 35-45 min and 85-95 min. The constant-infusion scan was quantified in two steps. First, the general linear model was used to fit regional time-activity curves with regressors for baseline metabolism, task-specific changes for the eyes-open and finger-tapping conditions, and movement parameters. Second, the Patlak plot was used for quantification of CMRGIu. Multiplication of the baseline regressor by beta-values from the general linear model yielded regionally specific time-activity curves for baseline metabolism. Further, task specific changes in metabolism are directly proportional to changes in the slope of the time-activity curve and hence to changes in CMRGIu. Results: Baseline CMRGIu from the constant-infusion scan matched that from the bolus application (test-retest variability, 1.1% +/- 24.7%), which was not the case for a previously suggested approach (variability, -39.9% +/- 25.2%, P < 0.001). Task-specific CMRGIu increased in the primary visual and motor cortices for eyes open and finger tapping, respectively (P < 0.05, familywise error corrected), with absolute changes of up to 2.1 mu mol/100 g/min and 6.3% relative to baseline. For eyes open, a decreased CMRGIu was observed in default-mode regions (P < 0.05, familywise error corrected). CMRGIu quantified with venous blood samples (n = 6) showed excellent agreement with results obtained from arterial samples (r > 0.99). Conclusion: Baseline glucose metabolism and task specific changes can be quantified in a single measurement with constant infusion of F-18-FDG and venous blood sampling. The high sensitivity and regional specificity of the approach offer novel possibilities for functional and multimodal brain imaging.