Factors Affecting Uptake of NaF-18 by the Normal Skeleton

BACKGROUND: The primary aim of this study was to examine if factors such as renal function, height, weight and age could affect the uptake of sodium fluoride-18 (NaF-18) by the normal bone. This is the first study to examine the possible factors that can influence NaF-18 uptake in the normal bone. METHODS: A retrospective study was done on NaF-18 PET/CT bone scans from January 2010 to May 2012 at our institution. All NaF-18 PET/CT studies used the same clinical protocol. Our excluding criteria were patients with abnormal renal function and patients with past history of cancer and metabolic bone diseases. Spearman’s correlation was used to analyze the data. RESULTS: From our study (n = 11 patients), no correlation was found between SUV(max) and serum creatinine and between SUV(max) and age. However, significant correlations were found between SUV(max) and height (cm) and between SUV(max) and weight (kg) for thoracic 5, 7, 12 and lumbar 2 vertebral levels. CONCLUSION: Based on our findings, SUV(max) values in NaF-18 PET/CT bone scans can vary depending on the patient’s height, weight and bone region. This information can be helpful in diagnosing and monitoring bone pathologies and can help explain the clinical findings.