Inclusion Criteria:  Patients for whom a 99mTc-biphosphonate bone scintigraphy is indicated; Pediatric patients for whom a 99mTc-biphosphonate bone scintigraphy is indicated for oncologic or infectious reasons Able to tolerate supine position Written consent  Exclusion Criteria:  Healthy subjects Pregnancy Unable of maintaining supine position for more than 15 minutes Refusal to sign the consent form Known allergy or hypersensitivity to 18F-NaF or any of its constituants.