Clinical utility of fluoride-18 positron emission tomography/CT in temporomandibular disorder with osteoarthritis: comparisons with 99mTc-MDP bone scan

Objectives: The purpose of this study was to compare the clinical utility of fluoride-18 positron emission tomography (F-18-PET)/CT with that of conventional Tc-99m-methylene diphosphonate (MDP) bone scan in temporomandibular disorder (TMD) with osteoarthritis. Methods: 24 patients with TMD who underwent both F-18-PET/CT and Tc-99m-MDP bone scans for diagnostic work-up were enrolled. The temporomandibular joint (TMJ)-to-skull uptake ratio, TMJ-to-muscle uptake ratio and TMJ-to-spine uptake ratio on 18F-PET/CT and the TMJ uptake ratio on bone scan were measured. Results: Of the 48 TMJs in 24 patients, 35 TMJs were diagnosed as TMD with osteoarthritis, 8 TMJs as TMD with anterior disc displacement (ADD), and the remaining 5 TMJs showed no evidence of TMD (NED). All three uptake ratios on F-18-PET/CT and the TMJ uptake ratio on the bone scan tended to be higher in TMD with osteoarthritis than in TMD with ADD or NED. Receiver operating characteristic (ROC) curve analysis for detecting TMD with osteoarthritis indicated that the TMJ-to-skull uptake ratio, TMJ-to-muscle uptake ratio and TMJ-to-spine uptake ratio on PET/CT (0.819, 0.771 and 0.813, respectively) showed higher area under the ROC curve value than the TMJ ratio on bone scan (0.714). The TMJ-to-skull uptake ratio on PET/CT showed the highest sensitivity (89%) and accuracy (81%) all uptake ratios. Conclusions: F-18-PET/CT can help diagnose TMD with osteoarthritis with superior diagnostic ability and is a suitable alternative modality to a conventional Tc-99m-MDP bone scan. Dentomaxillofacial Radiology (2013) 42, 29292350. doi: 10.1259/dmfr/29292350