Radionuclide three-phase whole-body bone imaging

Purpose: To describe the radionuclide three-phase whole-body bone imaging (TPWBBI) technique and discuss the usefulness of its application. Materials and Methods: TPWBBI was performed after a single intravenous injection of 555 to 925 MBq (15 to 25 mCi) Tc-99m MDP. Whole-body arterial flow (phase one) followed by blood-pool and tissue perfusion (phase two) images were obtained with the moving detector head speed set at 150 cm/minute and 40 cm/minute, respectively. Conventional whole-body static bone images (phase three) were obtained 3 hours later. Results: When 542 consecutive TPWBBI results were reviewed, 394 (166 extraskeletal and 228 skeletal) abnormalities were detected during phases one and two. The 166 extraosseous lesions included vascular diseases. abdominal aortic aneurysms and peripheral vascular diseases and renal abnormalities, liver abnormalities, ascites, and pleural effusions. Many of these were incidentally detected clinically significant findings and would not have been identified on conventional static bone images. It helps to differentiate among acute and chronic fractures, active and inactive inflammatory diseases such as arthritis or osteomyelitis, and Paget's disease. Conclusions: With a single injection of Tc-99m MDP, whole-body images obtained in the arterial phase, the blood-pool and tissue perfusion phase, and the static bone phase can identify many clinically significant skeletal and soft tissue abnormalities. TPWBBI can differentiate between active and inactive phases of different disease processes and thereby provide a diagnosis that is more specific than a conventional single-phase bone scan. It may be applicable as a tool for nuclear physical examination.