Vyska K, Magloire J R, Freundlieb C, Höck A, Becker V, Schmid A, Feinendegen L E, Kloster G, Stöcklin G, Schuier F J
Eur J Nucl Med. 1985;11(4):97-106. doi: 10.1007/BF00265041.
A method was developed to measure simultaneously the rate constants for glucose influx and glucose efflux, and the Michaelis-Menten constant (KM) and maximal velocity (Vmax) for glucose transport across the blood-brain barrier (BBB) in any selected brain area. Moreover, on the basis of a mathematical model, the local perfusion rate (LPR) and local unidirectional glucose transport rate (LUGTR) are calculated in terms of parameters of the time-activity curves registered over different brain regions; 11C-methyl-D-glucose (CMG) is used as an indicator. The transaxial distribution of activity in the organism is registered using dynamic positron-emission tomography (dPET). The method was used in 4 normal subjects and 50 patients with ischemic brain disease. In normals, the rate constant for CMG efflux was found to be 0.25 +/- 0.04 min-1 in the cortex and 0.12 +/- 0.02 min-1 in white matter. In the cortex, the KM was found to be 6.42 mumol/g and the Vmax was 2.46 mumol/g per minute. The LUGTR ranged from 0.43 to 0.6 mumol/g per minute in the cortex, and from 0.09 to 0.12 mumol/g per minute in white matter. The LPR was calculated to be 0.80-0.98 ml/g per minute for the cortex and 0.2-0.4 ml/g per minute for white matter. In patients with stroke, the ischemic defects appeared to be larger in CMG scans than in computed x-ray tomography (CT) scans. Prolonged reversible ischemic neurological deficit was associated with a significant fall in the LUGTR but no change in the LPR in the corresponding cerebral cortex. Normal LUGTR and significantly decreased LPR were registered in a patient with progressive occlusion of the middle cerebral artery. In a patient with transient ischemic attacks, a slightly reduced LPR and a disproportionally reduced LUGTR were observed before operation. After extra- and intracranial bypass surgery, the LPR became normal, whereas the LUGTR increased but did not achieve normal values.
已开发出一种方法，可同时测量葡萄糖流入和流出的速率常数，以及葡萄糖跨血脑屏障（BBB）在任何选定脑区转运的米氏常数（KM）和最大速度（Vmax）。此外，基于数学模型，根据在不同脑区记录的时间-活性曲线参数计算局部灌注率（LPR）和局部单向葡萄糖转运率（LUGTR）；使用11C-甲基-D-葡萄糖（CMG）作为指示剂。利用动态正电子发射断层扫描（dPET）记录生物体中活性的轴向分布。该方法应用于4名正常受试者和50名缺血性脑疾病患者。在正常受试者中，发现CMG在皮质中的流出速率常数为0.25±0.04 min-1，在白质中为0.12±0.02 min-1。在皮质中，KM为6.42 μmol/g，Vmax为每分钟2.46 μmol/g。LUGTR在皮质中范围为每分钟0.43至0.6 μmol/g，在白质中为每分钟0.09至0.12 μmol/g。计算得出皮质的LPR为每分钟0.80 - 0.98 ml/g，白质为每分钟0.2 - 0.4 ml/g。在中风患者中，CMG扫描显示的缺血缺损似乎比计算机X线断层扫描（CT）更大。长时间可逆性缺血性神经功能缺损与相应大脑皮质中LUGTR的显著下降相关，但LPR无变化。一名大脑中动脉进行性闭塞患者记录到正常的LUGTR和显著降低的LPR。一名短暂性脑缺血发作患者在手术前观察到LPR略有降低，LUGTR不成比例地降低。在颅外和颅内搭桥手术后，LPR恢复正常，而LUGTR增加但未达到正常值。
