Increase in [18F]-Fluoroacetate Uptake in Patients With Chronic Hemodynamic Cerebral Ischemia.

[18F]-fluoroacetate ((18)F-FACE) can be used for evaluating glial cell metabolism. Experimental studies have shown an increase in (18)F-FACE uptake in rodent models of cerebral ischemia. The aim of this study was to determine whether (18)F-FACE uptake is increased in the noninfarcted cerebral cortex in patients with hemodynamic ischemia owing to atherosclerotic internal carotid artery or middle cerebral artery disease

(11)C-methylaminoisobutyric acid (MeAIB) PET for evaluation of prostate cancer: compared with (18)F-fluorodeoxyglucose PET.

α-N-methyl-(11)C-methylaminoisobutyric acid ((11)C-MeAIB) is a selective substrate of system A amino acid transport, and known to accumulate in malignant lesions. The aim of this study was to evaluate the utility of MeAIB PET for the assessment of prostate cancer, compared with FDG PET

18F-FPYBF-2, a new F-18-labelled amyloid imaging PET tracer: first experience in 61 volunteers and 55 patients with dementia

Objective: Recently, we developed a benzofuran derivative for the imaging of β-amyloid plaques, 5-(5-(2-(2-(2-18F-fluoroethoxy)ethoxy)ethoxy)benzofuran-2-yl)- Nmethylpyridin-2-amine (18F-FPYBF-2) (Ono et al., 2011). The aim of this study was toassess the feasibility of 18F-FPYBF-2 as an amyloid imaging PET tracer in a firstclinical study with healthy volunteers and patients with various dementia and incomparative dual tracer study using 11C-Pittsburgh Compound B (11C-PiB).Methods: Sixty-one healthy volunteers (age: 53.7+/-13.1 y.o.; 19 male and 42 female;age range 24-79) and fifty-five patients with suspected dementia (Alzheimer\u27s Disease(AD); early AD: n=19 and moderate stage AD: n=8, other dementia: n=9, MildCognitive Impairment; MCI: n=16, cognitively normal: n=3) for first clinical studyunderwent static head PET/CT scan using 18F-FPYBF-2 at 50-70min after injection.Thirteen volunteers and fourteen patients also underwent dynamic PET scan at 0-50min at the same instant. Sixteen subjects (volunteers: n=5, patients with dementia:n=11) (age: 66.3+/-14.2 y.o.; 10 male and 6 female) were evaluated for comparativestudy (50-70min after injection) using 18F-FPYBF-2 and 11C-PiB on separate days,respectively. Quantitative analysis of mean cortical uptake was calculated using MeanCortical Index of SUVR (Standardized Uptake Value Ratio) based on the establishedmethod for 11C-PiB analysis using cerebellar cortex as control.Results: Studies with healthy volunteers showed that 18F-FPYBF-2 uptake was mainlyobserved in cerebral white matter and that average Mean Cortical Index at 50-70minwas low and stable (1.066+/-0.069) basically independent from age or gender. Inpatients with AD, 18F-FPYBF-2 uptake was observed both in cerebral white and graymatter and Mean Cortical Index was significantly higher (early AD: 1.288+/-0.134,moderate AD: 1.342+/-0.191) than those of volunteers and other dementia (1.018+/-0.057). In comparative study, the results of 18F-FPYBF-2 PET/CT were comparablewith those of 11C-PiB, and the Mean Cortical Index (18F-FPYBF-2: 1.173+/-0.215;11C-PiB: 1.435+/-0.474) showed direct proportional relationship with each other(p<0.0001).Conclusions: Our first clinical study suggest that 18F-FPYBF-2 is a useful PET tracerfor the evaluation of β-amyloid deposition and that quantitative analysis of MeanCortical Index of SUVR is a reliable diagnostic tool for the diagnosis of AD

18F-FPYBF-2, a new F-18 labelled amyloid imaging PET tracer: biodistribution and radiation dosimetry assessment of first-in-man 18F-FPYBF-2 PET imaging

ObjectiveRecently, a benzofuran derivative for the imaging of β-amyloid plaques, 5-(5-(2-(2-(2-18F-fluoroethoxy)ethoxy)ethoxy)benzofuran-2-yl)- N-methylpyridin-2-amine (18F-FPYBF-2) has been validated as a tracer for amyloid imaging and it was found that 18F-FPYBF-2 PET/CT is a useful and reliable diagnostic tool for the evaluation of AD (Higashi et al. Ann Nucl Med, https://doi.org/10.1007/s12149-018-1236-1, 2018). The aim of this study was to assess the biodistribution and radiation dosimetry of diagnostic dosages of 18F-FPYBF-2 in normal healthy volunteers as a first-in-man study.MethodsFour normal healthy volunteers (male: 3, female: 1; mean age: 40 ± 17; age range 25–56) were included and underwent 18F-FPYBF-2 PET/CT study for the evaluation of radiation exposure and pharmacokinetics. A 10-min dynamic PET/CT scan of the body (chest and abdomen) was performed at 0–10 min and a 15-min whole-body static scan was performed six times after the injection of 18F-FPYBF-2. After reconstructing PET and CT image data, individual organ time–activity curves were estimated by fitting volume of interest data from the dynamic scan and whole-body scans. The OLINDA/EXM version 2.0 software was used to determine the whole-body effective doses.ResultsDynamic PET imaging demonstrated that the hepatobiliary and renal systems were the principal pathways of clearance of 18F-FPYBF-2. High uptake in the liver and the gall bladder, the stomach, and the kidneys were demonstrated, followed by the intestines and the urinary bladder. The ED for the adult dosimetric model was estimated to be 8.48 ± 1.25 µSv/MBq. The higher absorbed doses were estimated for the liver (28.98 ± 12.49 and 36.21 ± 15.64 µGy/MBq), the brain (20.93 ± 4.56 and 23.05 ± 5.03µ Gy/MBq), the osteogenic cells (9.67 ± 1.67 and 10.29 ± 1.70 µGy/MBq), the small intestines (9.12 ± 2.61 and 11.12 ± 3.15 µGy/MBq), and the kidneys (7.81 ± 2.62 and 8.71 ± 2.90 µGy/MBq) for male and female, respectively.ConclusionsThe ED for the adult dosimetric model was similar to those of other agents used for amyloid PET imaging. The diagnostic dosage of 185–370 MBq of 18F-FPYBF-2 was considered to be acceptable for administration in patients as a diagnostic tool for the evaluation of AD