Assessment of physiologic intracranial calcification in healthy adults using 18 F-NaF PET/CT

Abstract

The aim of this research study was to determine the role of 18 F-sodium fluoride ( 18 F-NaF) PET/CT imaging in the assessment of physiologic molecular calcification in the intracranial structures. We also examined the association of 18 F-NaF accumulation with age as well as Hounsfield unit (HU) in certain anatomic sites that are known to calcify with normal aging. Methods: A total of 78 healthy subjects from the Cardiovascular Molecular Calcification Assessed by 18 F-NaF PET/CT (CAMONA) clinical trial (38 women and 40 men) were included in this retrospective study. The mean age was 45.28 ± 14.15 y (age range, 21–75 y). SUV mean was used to measure 18 F-NaF accumulation in the choroid plexus and epithalamus (pineal gland and habenula). Maximum HU was also measured for each region of interest. Correlation analysis was conducted to assess the association between parameters. Results: Mean SUV mean was 0.42 ± 0.26 in the right choroid plexus, 0.39 ± 25 in the left choroid plexus, and 0.23 ± 0.08 in the epithalamus. Significant positive correlations were present between 18 F-NaF uptake and age in the right choroid plexus (r 5 0.61, P, 0.0001), left choroid plexus (r 5 0.63, P, 0.0001), and epithalamus (r 5 0.36, P 5 0.001). 18 F-NaF uptake significantly correlated with HU in the right choroid plexus (r 5 0.52, P, 0.0001), left choroid plexus (r 5 0.57, P, 0.0001), and epithalamus (r 5 0.25, P 5 0.03). Conclusion: 18 F-NaF could be used in the assessment of physiologic calcification in several intracranial structures. We report significant associations between 18 F-NaF uptake and aging as well as HU in the calcified choroid plexus and epithalamus. Our findings further support the growing interest to use 18 F-NaF for detecting extraosseous, molecular calcification, and this powerful probe has potential applications in the evaluation of various age-related, neurodegenerative brain processes.