Quantitative bone SPECT analysis of mandibular condyles in an asymptomatic population: an approach to normal reference values

Bone scintigraphy is an extremely valuable technique in diagnosis and treatment planning for patients with condylar hyperplasia (CH). The main objective of this study was to develop approach determine normal activity values the mandibular condyles, adjusted age sex, through quantitative analysis bone single-photon emission computed tomography (SPECT) on a condyle-by-condyle basis compare these those control group comprising confirmed CH. Technetium 99 m-methylene diphosphonate (99mTc-MDP) SPECT studies condyles were performed no pathology analysis. Regions interest drawn slices representing upper, middle, inferior thirds each condyle summation transaxial whole (three-dimensional approach). clivus used internal validation ratios calculated. These compared between ‘normal’ ‘diseased’ condyles. A total 144 25 CH analysed. Differences evaluated coefficient variation. In patients, summed image showed lowest variability: range 0.3–1.28 (median 0.74). quantile regression model significant differences respect but not age. Mann–Whitney test diseased (P < 0.0001).