Principle: Imaging early changes in bone tissue metabolism. The radiopharmaceutical accumulates to an increased extent in sites of increased bone metabolism, and to a reduced extent in osteolytic deposits. The examination is highly sensitive but poorly specific and cannot always distinguish the cause of metabolic changes in bone. It may also show a fracture, degenerative lesion, or metastasis. However, scintigraphy shows a metabolically active bone process several months earlier than X-rays, which is particularly important in the diagnosis of bone metastases. Indications: dg. benign and malignant bone tumours monitoring of bone metastases at time intervals detection of traumatic bone changes diagnosis of osteomyelitis diagnosis of M.Perthes diagnosis of degenerative joint changes monitoring of postoperative conditions in endoprostheses diagnosis of suspected bionecrosis, sacroilitis … Patient preparation: None increased fluid intake Duration of examination: approx. 2.5 – 5 hours. The first phases of the examination are performed immediately after the application of the radiopharmaceutical (about 10 minutes) and the bone phase is examined after about 2 – 4 hours (the time factor depends on the age and weight of the patient), the patient does not need to spend this time at the nuclear medicine workplace. The second recording takes about 20 minutes. Radiopharmaceutical: 99mTc – hydroxymethylene diphosphonate (oxydronate) Method of application: Intravenous Examination methodology: The patient is injected intravenously with the radiopharmaceutical in the supine position. The blood supply to the pathological process is assessed during an approximately 10-minute scan. After the injection, the patient waits 2-4 hours for the radiopharmaceutical to be picked up in the bone structures. The technician is informed about the time of the next scan. The patient does not have to spend this time in the nuclear medicine department. Before the second scan, he/she is urinated and cleansed of all metallic objects. This part takes about 20 minutes. When the sensitivity and specificity of the scan increases, targeted SPECT is added.