Correlation of early-phase 18F-florbetapir (AV-45/Amyvid) PET images to FDG images: preliminary studies

Abstract

Preliminary results showed that the distribution patterns of R(1) and pAV-45 images are highly correlated with normalized FDG images, and the initial 5-min early time frame of 1-6 min is potentially useful in providing complementary FDG-like information to the amyloid plaque density by late-phase AV-45 images.

Quantification of Blood Flow-Dependent Component in Estimates of Beta-Amyloid Load Obtained Using Quasi-Steady-State Standardized Uptake Value Ratio

“…), which previously has been shown to provide accurate estimates. 35 No correction was made for blood volume content in the TACs in lack of blood radioactivity information. However, blood volume content should in general be similar between target and reference regions thus it should largely cancel out when estimating R 1 with any remaining effect likely parallel to R 1 .…”

Dual-phase amyloid PET: hitting two birds with one stone

“…The data available so far show that early phase images have strong similarities with FDG PET images in AD and frontotemporal lobar degeneration [10,[12][13][14], can distinguish MCI from healthy controls [15], and recent evidence suggests a potential diagnostic advantage also in patients with cerebral amyloid angiopathy [16].…”

“…The concept of dual-phase scanning is not new; it has been tested both with 11C-PIB and with 18F-Florbetapir and is mainly linked to the fact that amyloid tracers have high lipophilicity, which makes them good perfusion surrogates [10,11].…”

Comment on Hsiao et al.: Correlation of early-phase 18F-florbetapir (AV-45/Amyvid) PET images to FDG images: preliminary studies

“…Dear Sir, I read with interest the paper by Hsiao et al [1] in which they compared the early regional cerebral distribution of the putative amyloid imaging agent 18 F-florbetapir with that of 18 F-FDG. It has long been recognized that the early cerebral distribution of lipophilic tracers reflects regional perfusion [2][3][4] and indeed it was suggested many years ago that a single injection might provide both perfusion and receptor binding information by imaging at two time points [5,6].…”