First experience with early dynamic (18)F-NaF-PET/CT in patients with chronic osteomyelitis

This study investigates whether early dynamic positron emission tomography/computed tomography (edPET/CT) using (18)F-sodium fluoride-((18)F-NaF) is feasible in depicting early phases of radiotracer distribution in patients with chronic osteomyelitis (COM).

A total of 12 ed(18)F-NaF-PET/CT examinations were performed on 11 consecutive patients (2 female, 9 male; age 53 ± 12 years) in list mode over 5 min starting with radiopharmaceutical injection before standard late (18)F-NaF-PET/CT. Eight consecutive time intervals (frames) were reconstructed for each patient: four 15 s, then four 60 s. Several volumes of interest (VOI) were selected, representing the affected area as well as different reference areas within the bone and soft tissue. Maximum and mean ed standardized uptake values (edSUVmax, edSUVmean, respectively) were calculated in each VOI during each frame to measure early fluoride influx and accumulation. Results were compared between affected and non-affected (contralateral) bones.

Starting in the 31-45 s frame, the affected bone area showed significantly higher edSUVmax and edSUVmean compared to the healthy contralateral region. The affected bone areas also significantly differed from non-affected contralateral regions in conventional late (18)F-NaF-PET/CT.

This pilot study suggests that, in patients with COM, ed(18)F-NaF -PET offers additional information about early radiotracer distribution to standard (18)F-NaF -PET/CT, similar to a three-phase bone scan. The results should be validated in larger trials which directly compare ed(18)F-NaF-PET to a three-phase bone scan.