Alterations in cerebral glucose metabolism can be indicative of both normal and pathological aging processes. In this retrospective study, we evaluated global and regional neurological glucose metabolism in 73 healthy individuals (mean age: 35.8 ± 13.1 years; 82.5% female) using 18F-Fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT). This population exhibited a low prevalence of comorbidities associated with cerebrovascular risk factors. We utilized ¹⁸F-FDG-PET/CT imaging and quantitative regional analysis to assess cerebral glucose metabolism. A statistically significant negative correlation was found between age and the global standardized uptake value mean (SUVmean) of FDG uptake (p = 0.000795), indicating a decrease in whole-brain glucose metabolism with aging. Furthermore, region-specific analysis identified significant correlations in four cerebral regions, with positive correlations in the basis pontis, cerebellar hemisphere, and cerebellum and a negative correlation in the lateral orbital gyrus. These results were further confirmed via linear regression analysis. Our findings reveal a nuanced understanding of how aging affects glucose metabolism in the brain, providing insight into normal neurology. The study underscores the utility of ¹⁸F-FDG-PET/CT as a sensitive tool in monitoring these metabolic changes, highlighting its potential for the early detection of neurological diseases and disorders related to aging.

(1) Background: Glioblastoma (GBM) is the most common primary malignant brain tumor in adults, with an aggressive disease course that requires accurate prognosis for individualized treatment planning. This study aims to develop and evaluate a radiomics-based machine learning (ML) model to estimate overall survival (OS) for patients with GBM using pre-treatment multi-parametric magnetic resonance imaging (MRI). (2) Methods: The MRI data of 865 patients with GBM were assessed, comprising 499 patients from the UPENN-GBM dataset and 366 patients from the UCSF-PDGM dataset. A total of 14,598 radiomic features were extracted from T1, T1 with contrast, T2, and FLAIR MRI sequences using PyRadiomics. The UPENN-GBM dataset was used for model development (70%) and internal validation (30%), while the UCSF-PDGM dataset served as an external test set. The NGBoost Survival model was developed to generate continuous probability estimates as well as predictions for 6-, 12-, 18-, and 24-month OS. (3) Results: The NGBoost Survival model successfully predicted survival, achieving a C-index of 0.801 on internal validation and 0.725 on external validation. For 6-month OS, the model attained an AUROC of 0.791 (95% CI: 0.742–0.832) and 0.708 (95% CI: 0.654–0.748) for internal and external validation, respectively. (4) Conclusions: The radiomics-based ML model demonstrates potential to improve the prediction of OS for patients with GBM.

Atherosclerosis, a leading cause of mortality and morbidity worldwide, involves inflammatory processes that result in plaque formation and calcification. The early detection of the molecular changes underlying these processes is crucial for effective disease management. This study utilized positron emission tomography/computed tomography (PET/CT) with [¹⁸F] sodium fluoride (NaF) as a tracer to visualize active calcification and inflammation at the molecular level. Our aim was to investigate the association between cardiovascular risk factors and [¹⁸F] NaF uptake in the left and right common carotid arteries (LCC and RCC). A cohort of 102 subjects, comprising both at-risk individuals and healthy controls, underwent [¹⁸F] NaF PET/CT imaging. The results revealed significant correlations between [¹⁸F] NaF uptake and cardiovascular risk factors such as age (β = 0.005, 95% CI 0.003–0.008, p < 0.01 in LCC and β = 0.006, 95% CI 0.004–0.009, p < 0.01 in RCC), male gender (β = −0.08, 95% CI −0.173–−0.002, p = 0.04 in LCC and β = −0.13, 95% CI −0.21–−0.06, p < 0.01 in RCC), BMI (β = 0.02, 95% CI 0.01–0.03, p < 0.01 in LCC and β = 0.02, 95% CI 0.01–0.03, p < 0.01 in RCC), fibrinogen (β = 0.006, 95% CI 0.0009–0.01, p = 0.02 in LCC and β = 0.005, 95% CI 0.001–0.01, p = 0.01), HDL cholesterol (β = 0.13, 95% CI 0.04–0.21, p < 0.01 in RCC only), and CRP (β = −0.01, 95% CI −0.02–0.001, p = 0.03 in RCC only). Subjects at risk showed a higher [¹⁸F] NaF uptake compared to healthy controls (one-way ANOVA; p = 0.02 in LCC and p = 0.04 in RCC), and uptake increased with estimated cardiovascular risk (one-way ANOVA, p < 0.01 in LCC only). These findings underscore the potential of [¹⁸F] NaF PET/CT as a sensitive tool for the early detection of atherosclerotic plaque, assessment of cardiovascular risk, and monitoring of disease progression. Further research is needed to validate the technique’s predictive value and its potential impact on clinical outcomes.

A quantification technique for costal cartilage calcification using ¹⁸F-sodium fluoride–positron emission tomography/computed tomography (¹⁸F-NaF-PET/CT) has yet to be established, and the effects of aging and other demographic variables on costal cartilage calcification remain understudied. This study aims to introduce a quantification methodology for assessing costal cartilage calcification using ¹⁸F-NaF-PET/CT, assess age-related changes in its ¹⁸F-NaF uptake in females and males, and examine the relationship between its ¹⁸F-NaF uptake and CT attenuation as well as ¹⁸F-NaF uptake and coronary artery calcification. In this retrospective study, we analyzed subjects from the Cardiovascular Molecular Calcification Assessed by ¹⁸F-NaF PET/CT (CAMONA) clinical trial. This study evaluated 130 subjects (mean age 48.7 ± 14.5 years; n = 67 females). We manually generated regions of interest overlying the costal cartilages from ribs 8 to 10 on the left side, carefully avoiding osseous uptake from adjacent ribs and sternum, to measure cartilaginous ¹⁸F-NaF uptake. Non-parametric statistical analyses (Spearman correlations, Mann–Whitney U tests, Kruskal–Wallis tests) and receiver operating characteristic analysis were performed to evaluate sex-specific age-related changes in uptake, correlations between imaging parameters, and associations with coronary artery calcium (CAC) score. In females, the mean ¹⁸F-NaF uptake (as assessed by average SUV_mean) was 0.69 ± 0.38 while the corresponding mean Hounsfield Unit (HU) was 108.0 ± 40.0. In males, the mean ¹⁸F-NaF uptake (as assessed by average SUV_mean) was 0.63 ± 0.22, and the mean HU was 104.0 ± 24.0. There was a significant correlation between ¹⁸F-NaF uptake and age in both females (p = 0.003, r = 0.36) and males (p < 0.0001, r = 0.63). The correlation was significantly stronger in males than females (Fisher’s z-test, p = 0.040). There was a significant correlation between CAC score and costal cartilage SUV_mean in both females (r = 0.26, p = 0.036) and males (r = 0.51, p < 0.0001). This study introduces a quantification technique to assess costal cartilage calcification using ¹⁸F-NaF-PET/CT and demonstrates that the calcification increases with age, more strongly in males than in females, and ¹⁸F-NaF uptake is correlated with CAC score. This technique can be applied to other cartilages of interest, in both physiological and pathological conditions, to assess the effects of aging and various demographic variables on cartilage calcification.

Background: Cardiovascular disease is a leading cause of illness and death globally, primarily due to atherosclerosis. This disease reduces blood flow and oxygen delivery to organs, and when it affects the carotid arteries, it can lead to cognitive impairment and dementia. In a population of 104 individuals, comprising both healthy controls and individuals at elevated risk for developing cardiovascular diseases (CVD) due to identified risk factors, we used PET imaging with ¹⁸F-fluorodeoxyglucose (FDG) to assess cerebral glucose metabolism and ¹⁸F-sodium fluoride (NaF) to detect atherosclerotic calcification. Our statistical analysis revealed significant differences in metabolic activity between healthy and at-risk individuals in specific brain regions. ¹⁸F-FDG uptake in the brain varied inversely with respect to the clinical assessment of cardiovascular risk in regions such as the cuneus (β = −0.030, SE = 0.014, p = 0.035), middle occipital gyrus (β = −0.032, SE = 0.011, p = 0.005), and posterior cingulate gyrus (β = −0.032, SE = 0.015, p = 0.044). In contrast, areas including the basis pontis (β = 0.025, SE = 0.012, p = 0.038) and the pons (β = 0.034, SE = 0.013, p = 0.008) exhibited direct correlations. Notably, carotid ¹⁸F-NaF uptake had inverse associations with ¹⁸F-FDG uptake in the cerebellum (β = −0.825, SE = 0.354, p = 0.021), medulla (β = −0.888, SE = 0.405, p = 0.029), and posterior cingulate gyrus (β = −1.253, SE = 0.567, p = 0.028), while increased carotid calcification influenced metabolic activity in the fusiform gyrus (β = 1.660, SE = 0.498, p = 0.001) and globus pallidus (β = 1.505, SE = 0.571, p = 0.009). We observed that atherosclerotic plaque accumulation, especially in the carotid arteries, has potential implications for metabolic changes in brain regions governing cognition, emotion, sensory perception, and motor activities. Our findings underscore the possible early interventions that can be used to preempt or delay cognitive deterioration linked with cardiovascular ailments.

Purpose ¹⁸F-fluorodeoxyglucose (FDG) Positron Emission Tomography (PET)/Computerized Tomography (CT) is an important imaging modality in oncology, but its use in spinal cord assessment is limited due to a lack of baseline metabolic reference values. Regional spinal cord FDG uptake, especially in healthy populations, remains poorly defined, limiting accurate delineation between physiological and pathological uptake. The study aimed to quantify regional FDG uptake in the cervical, thoracic, and lumbar spinal cord in healthy adults, and evaluate associations between FDG uptake and demographic factors, including age, sex, body mass index (BMI), and inflammatory/metabolic biomarkers. A secondary aim was to apply artificial intelligence (AI)-driven segmentation to facilitate standardized region-of-interest extraction across spinal cord levels. Methods This was a retrospective, cross-sectional observational study conducted using data from the CAMONA clinical trial at Odense University Hospital, Denmark. 76 healthy adult participants (mean age 44.66 ± 14.04 years; 53.9% male) were selected from a total of 139 subjects in the CAMONA trial. All participants were free from chronic medical conditions. Primary outcomes include mean standardized uptake values (SUVmean) of FDG in the cervical, thoracic, and lumbar spinal cord regions. Secondary outcomes include correlations of SUVmean with age, sex, BMI, HbA1c, and inflammatory biomarkers (CRP, WBC, homocysteine, fibrinogen). Participants underwent FDG PET/CT imaging 180 min post-injection of 4.0 MBq/kg FDG. Using TotalSegmentator, an AI-driven segmentation tool, the spinal cord was delineated into cervical, thoracic, and lumbar volumes of interest (VOIs). Regional SUVmeans were calculated and analyzed. Statistical tests included one-way ANOVA with Tukey’s post-hoc, Spearman/Pearson correlations and t-tests to assess associations with age, sex, BMI, and inflammatory/metabolic biomarkers. Results FDG uptake was highest in the cervical spinal cord (SUVbw 1.36 ± 0.23), followed by the lumbar (0.85 ± 0.18) and thoracic (0.76 ± 0.17) regions (p < 0.001); this regional ordering was preserved after lean-body-mass-normalized SUV (SUL) recomputation. No significant associations were found with age or sex. BMI correlated positively with SUVbw across all regions (ρ = 0.34–0.47, all p ≤ 0.003); under SUL, the cervical and thoracic associations attenuated to non-significance (cervical ρ = +0.13, p = 0.255; thoracic ρ = +0.17, p = 0.151), whereas a residual lumbar association persisted (ρ = +0.32, 95% CI + 0.09 to + 0.52, p = 0.004). A nominal association between HbA1c and cervical uptake (ρ = 0.24, p = 0.040) did not survive Bonferroni correction for multiple comparisons (α = 0.0033) and is reported as exploratory. Inflammatory markers showed no significant correlation in any spinal cord region. Conclusion FDG PET/CT reveals consistent regional variation in spinal cord metabolic activity, with highest uptake in the cervical region. Normative uptake was stable across age and sex but showed a positive association with BMI when SUV was normalized to total body weight that was largely abolished after lean-body-mass normalization (SUL) in the cervical and thoracic regions but persisted in the lumbar region (lumbar SUL ρ = +0.32, 95% CI + 0.09 to + 0.52, p = 0.004). These findings offer foundational data for clinical interpretation and differentiation between physiology and pathology of spinal FDG PET/CT uptake and demonstrate the feasibility of AI-driven segmentation for standardized region-of-interest extraction in spinal imaging analysis.