Medical Student Sidney Kimmel Medical College, Thomas Jefferson University Sidney Kimmel Medical College, Thomas Jefferson University
Introduction: The early detection of osteoporosis is crucial for optimal patient management and risk reduction in spinal surgery. Current diagnostic methods, such as dual-energy X-ray absorptiometry (DEXA) and traditional CT, often identify osteoporosis after significant bone loss has already occurred. In contrast, sodium fluoride (18F-NaF) PET/CT can assess bone metabolic activity that may reflect osteoporotic development prior to the onset of structural alterations visible on conventional imaging.
Methods: Our study participants are a 67-year-old female (Case 1) and a 25-year-old female (Case 2) recruited from the Cardiovascular Molecular Calcification Assessed by 18F-NaF PET/CT (CAMONA) clinical trial (NCT01724749). Case 1 has a body mass index (BMI) of 22 kg/m2, history of cardiovascular disease (CVD), a smoking history of 8 pack-years, and active alcohol consumption. Case 2 has a BMI of 28 kg/m2, no history of CVD, a smoking history of 5 pack-years, and active alcohol consumption. Both patients underwent NaF PET/CT imaging 90 minutes post-radiotracer injection. Artificial intelligence (AI)-based quantification was used to determine the mean standardized uptake value (SUVmean) for NaF uptake in each lumbar vertebral body (VB). OsiriX MD software was used to calculate average Hounsfield Units (HU) in each VB.
Results: Average L1-L5 density was 79.60 HU for Case 1 and 214 HU for Case 2, suggesting the presence of significant osteoporosis in Case 1 compared to Case 2, which showed no structural abnormalities in the vertebrae. Mean lumbar NaF uptake was 3.70 kBq/mL and 7.20 kBq/mL for Case 1 and Case 2, respectively.
Conclusion : Elevated NaF uptake may represent accelerated bone turnover in early-stage, subclinical osteoporosis. As trabecular bone is lost in advanced disease, NaF retention in the lumbar spine decreases. Our findings demonstrate the potential of 18F-NaF PET/CT to characterize metabolic alterations in the spine that precede the structural alterations of osteoporosis, thereby facilitating patient selection and clinical risk assessment for spine surgery.