Comparison of [18F] NaF PET/CT Analysis Methods and Derivation of a Semi-population Input Function for Site Specific Measurements of Bone Formation in a Population With Chronic Kidney Disease Mineral and Bone Disorder

Abstract

\n PurposeImplementation and comparison of non-invasive dynamic and static whole-body (WB) [18F]NaF PET/CT scan methods to replace invasive bone biopsy, used for quantitative analysis of bone clearance in patients with chronic kidney disease - mineral and bone disorder (CKD-MBD).MethodsSeventeen patients with CKD-MBD underwent a 60-minute dynamic scan followed by a 30-minute static WB scan. Tracer kinetics in four thoracic vertebrae were analyzed using non-linear regression and Patlak analysis using image-derived arterial input functions. We validated the use of a semi-population input function in this population.ResultsSkeletal plasma clearance (Ki) from Patlak analyses correlated well with non-linear regression analysis, but Ki-results using Patlak analysis were lower compared to Ki-results using non-linear regression analysis. However, no significant difference was found between Ki obtained by static WB scans and Ki obtained by dynamic scans using non-linear regression analysis (p=0.29). ConclusionOur results show good correlation between dynamic and static analysis of skeletal plasma clearance with no significant difference between the Ki-results obtained by non-linear regression analysis and the more clinically suitable static scan analysis method. We found lower Ki-results when Patlak analysis was applied. Thus, WB [18F]NaF PET/CT scans can be applied in future studies to measure Ki in CKD-BMD patients, but the results should not be compared uncritically with results obtained by dynamic scans analysis.