Effect of Vascular Activity in the Determination of Rate Constants for the Uptake of ¹⁸F-Labeled 2-Fluoro-2-Deoxy-D-Glucose: Error Analysis and Normal Values in Older Subjects

Abstract

Summary:Regional cerebral blood volume (CBV) can be calculated using data obtained during the kinetic analysis of 18F-labeled 2-fluoro-2-deoxY-D-glucose (FDG) uptake measured by positron emission tomography (PET). As a result the influence of vascular activity upon the determi nation of FDG rate constants can be minimized. The method is investigated by simulation experiments and by analysis of PET studies on seven older, healthy human volunteers aged 52-70 years. The accuracy of measured FDG rate constants kl' k2, and k3' obtained either by omitting the early portion of the uptake curve or by ex plicit inclusion of CBV as a fit parameter, is compared. The root mean square error in measured rate constant for the latter method is equivalent to that obtained by omit ting the first 2. 5-3 min of tissue data and neglecting the CBV term. Hence, added information about the physio logical state of the tissue is obtained without compro-The use of 18 F-labeled 2-f1uoro-2-deoxY-D-glu cose (FDG) and positron emission tomography (PET) to determine regional cerebral glucose was introduced in humans by Reivich et al. (1979), using the deoxyglucose model of Sokoloff et al. (1977), and extended to include phosphatase activity by Phelps et al. (1979a). Since then the method has been used to study a variety of pathological condi tions (Phelps et aI. , 1982; Yamamoto et aI. , 1984). The method estimates regional glucose utilization by comparing the observed tissue activity concen-

Glucose metabolism and rate constants in Alzheimer's disease examined with dynamic positron emission tomography scan

“…In addition, the half-life of the FDG was slightly longer. The data from compartment analysis, taking into account the vascular volume, produced almost the same values as ours (18). Statistically significant reductions in the rate constants of Alzheimer's patients did occur predominantly in k3* of the bilateral parietal and the left temporal regions, with K1* reduced only in the right parietal region, and k2* decreased in the bilateral temporal regions and left frontal region.…”

Cerebral transport and metabolism of 1‐11C‐D‐glucose during stepped hypoglycemia

“…We therefore elected to use a 10-to 20-second infusion rather than add another parameter to the estimation. We included a term for i~ntravascular radioactivity based on the volume of the intravascular compartment (compartment 1) as has been suggested for "C-Dglucose [33f and for FDG [38,[41][42][43]. We used the measured value for CBV [2!1] for this volume.…”

Scaled Subprofile Model: A Statistical Approach to the Analysis of Functional Patterns in Positron Emission Tomographic Data

“…PET scans were performed during a controlled resting state: Eyes were patched and auditory stimulation (music, intermittent verbal briefings) was delivered through acoustically-isolated earphones. Serial FDG/ PET images were acquired using the PC 4600 PET scanner (Kearfott and Carroll, 1984), radial arterial blood was sampled at predetermined intervals, and compart mental rate constants and cerebral blood volume were calculated for 28 standardized gray-matter regions of in terest as described by Evans et al (1986) (Fig. 3).…”