Objective.The objective of this study was to compare glucose metabolism and atrophy, in the precuneus and cingulate cortex, in patients with Alzheimer’s disease (AD) and mild cognitive impairment (MCI), using FreeSurfer.Methods.47 individuals (17 patients with AD, 17 patients with amnestic MCI, and 13 healthy controls (HC)) were included. MRI and PET images using¹⁸F-FDG (mean injected dose of 185 MBq) were acquired and analyzed using FreeSurfer to define regions of interest in the hippocampus, amygdala, precuneus, and anterior and posterior cingulate cortex. Regional volumes were generated. PET images were registered to the T1-weighted MRI images and regional uptake normalized by cerebellum uptake (SUVr) was measured.Results.Mean posterior cingulate volume was reduced in MCI and AD. SUVr were different between the three groups: mean precuneus SUVr was 1.02 for AD, 1.09 for MCI, and 1.26 for controls (p<0.05); mean posterior cingulate SUVr was 0.96, 1.06, and 1.22 for AD, MCI, and controls, respectively (p<0.05).Conclusion.We found graduated hypometabolism in the posterior cingulate cortex and the precuneus in prodromal AD (MCI) and AD, whereas atrophy was not significant. This suggests that the use of¹⁸F-FDG in these two regions could be a neurodegenerative biomarker.

The aim of this study was to evaluate the prognostic value of F-FDG PET/CT by predicting histopathological findings in the pretransplant evaluation of patients with hepatocellular carcinoma (HCC). F-FDG PET/CT findings of 34 patients with HCC who underwent liver transplantation were reviewed retrospectively. Visual and quantitative analysis (tumor standardized uptake values normalized to the background activity of the liver: SUVmax T/L) was done. PET tumor characteristics were compared with the histological analysis (differentiation and microvascular invasion). All patients were followed up (mean, 12 months). Ten patients showed tumoral uptake greater than background activity (PET+). Higher-grade tumor was more common in the F-FDG-avid tumor group (P < 0.05). PET+ also showed more microvascular invasion at explant pathology (P < 0.05). Only 1 patient PET+ developed HCC early recurrence (4 months) with an SUVmax T/L of 1.64. F-FDG uptake is predictive for microvascular invasion and tumor differentiation. This examination has a prognostic value regarding tumor recurrence after liver transplantation for HCC.

The aim of this study is to compare regional cerebral metabolic rate of glucose metabolism and amyloid-β density in patients with Alzheimer disease (AD), mild cognitive impairment (MCI), and healthy elderly subjects. Eighteen patients (including 6 AD, 5 amnestic MCI, and 7 controls) were enrolled at the University Hospital of Tours, France, and submitted to clinical, neuropsychological, and MRI examinations. PET images using F-florbetapir (266 MBq) and F-FDG (185 MBq) were acquired. SUV ratios in specific regions were defined using PMOD3.2 software. The mean values of F-FDG SUV ratio were significantly lower in frontal, anterior cingulate, and temporal regions in MCI patients than in normal elderly (-15%, -22%, and -11%, respectively). Alzheimer disease patients showed global cerebral metabolic rate of glucose metabolism decrease, especially in parietal and precuneus regions (-15% and -13% compared with healthy control subjects). Only precuneus cortex showed an increased F-florbetapir uptake in AD. There was no other significant regional difference in the amyloid-β density. In this study, we observed regional brain metabolic changes between MCI, AD, and controls, whereas only precuneus showed an increased amyloid-β density in AD. F-florbetapir PET analysis needs to be visual and global, whereas F-FDG analysis can be regional.

F-FDG PET/CT of a patient with inflammatory lower back pain reveals diffuse bony metastases, similar to the "superscan" found on a Tc-methylene diphosphonate scintigraphy, and also demonstrates a prostatic lesion which appears to be a poorly differentiated prostate adenocarcinoma.

Purpose: The aim of this study was to assess the results of cadmium zinc telluride (CZT)- single-photon emission computed tomography (SPECT) myocardial flow reserve (MFR) in coronary artery disease (CAD) screening regarding clinical risk and its correlation to invasive coronary angiography (ICA).Methods: A total of 137 patients (61 male and 76 female) referred for CAD screening myocardial perfusion imaging (MPI) between November 2018 and April 2020 were included in the CFR-OR prospective trial. The 10-year risk of cardiovascular death according to the European Society of Cardiology (SCORE) was calculated. SPECT 1-day 99mTc-tetrofosmin protocol was acquired on CZT cardiac-dedicated pinhole cameras. Low-dose thoracic CT was used for coronary calcium score (CCS) evaluation. ICA, when performed within 3 months, was also analyzed.Results: Mean SCORE and mean global MFR were, respectively, 4 ± 3.1% and 2.50 ± 0.74; 34 patients had impaired CFR (using a threshold of 2). There was a significant inverse correlation between MFR and SCORE (p = 0.006), gender (p = 0.019), and number of cardiovascular risk factors (p = 0.01). MFR was significantly reduced in patients with CCS above 1 (p = 0.01). No significant correlation was found between MFR and individual cardiovascular risk factors (dyslipidemia, hypertension, diabetes, or family history of CAD). A total of 23 patients underwent ICA. Global MFR SPECT sensitivity and specificity were 83.3 and 100 %, respectively, with an area under the curve of 0.94.Conclusion: Adding MFR to SPECT MPI for CAD screening on CZT camera may contribute to high-risk patient identification and enhance diagnostic performances. MFR could help physician decision to perform ICA.