Bone metabolism measured with six quantification methods using ¹⁸F-PET: World Molecular Imaging Congress, San Diego, 2011

The non-invasive assessment of regional bone metabolism using 18F-fluoride positron emission tomography (18F-PET) can aid in understanding the pathophysiology of metabolic bone diseases such as osteoporosis. The aim of this study was to evaluate the relationship between five different quantification methods against the three compartment four parameter model (Ki-4k), used as the gold standard, for the measurement of regional bone turnover (Ki, representing the net plasma clearance to bone mineral) using 18F-PET at the hip and lumbar spine. Methods: Twelve healthy postmenopausal women aged 52-71 years, with no history of metabolic bone disease (except untreated osteoporosis in the spine) or on current treatments affecting skeletal metabolism, were recruited. Each subject had 60 min dynamic 18F-PET scans at the lumbar spine and hip on two separate occasions with injected activities of 90 MBq and 180 MBq respectively. Arterial input functions were obtained from images of the aorta in the same datasets in order to determine Ki values at both the sites using a Ki-4k, three compartment three parameter model (Ki-3k), Patlak analysis (Ki-Pat), spectral analysis (Ki-Spec), deconvolution analysis (Ki-Decon) and SUV. The significance of the Spearman rank correlation test are expressed as p-values as * for p