Bone scintigraphy has three phases: the dynamic or perfusion (flow) phase—immediate images showing blood supply; the blood‑pool (soft‑tissue) phase—taken minutes after injection to assess regional hyperemia and soft‑tissue involvement; and the delayed (bone) phase—images obtained hours later that reflect osteoblastic activity and bone turnover, aiding detection of fractures, infection, tumors, and metabolic bone disease.

A three-phase bone scan has: 1) flow (dynamic) images showing blood supply immediately after tracer injection; 2) blood‑pool (soft‑tissue) images minutes later showing local hyperemia; 3) delayed (bone) images hours later showing osteoblastic activity. Increased flow and pool with matching delayed uptake suggests acute infection or fracture; increased delayed uptake alone suggests chronic remodeling or tumor. Photopenic areas may indicate avascular necrosis. Correlate clinically.

A three‑phase bone scan includes: 1) Flow phase — immediate dynamic images during tracer injection to assess blood supply; 2) Blood‑pool (soft‑tissue) phase — a few minutes later showing soft‑tissue perfusion and hyperemia; 3) Delayed (bone) phase — 2–4 hours later when bone uptake reflects osteoblastic activity and metabolism. SPECT or SPECT/CT may be added for anatomic detail.

A three‑phase scan is a nuclear medicine bone study using a radiotracer and imaging at three times: immediate flow (perfusion), early blood‑pool (soft tissue), and delayed bone images. It assesses blood supply, inflammation, and bone metabolism to detect fractures, infection (osteomyelitis), arthritis, or prosthetic loosening. It's noninvasive, requires IV tracer injection, and helps localize active bone pathology.

A three‑phase bone scan typically takes about 2–4 hours from injection to finish. The first (flow) phase is imaged immediately for a few minutes, the second (blood‑pool) phase takes around 5–10 minutes soon after, and the delayed (bone) phase is done 2–4 hours later and usually requires 20–60 minutes of imaging. Total appointment time includes waiting between phases.

A four‑phase bone scan is a nuclear medicine test using a technetium‑99m bone tracer and serial images to assess blood flow, soft‑tissue pooling, and bone uptake. Images are obtained immediately (flow), minutes after injection (blood‑pool), and at 2–4 hours and sometimes 24 hours (delayed) to evaluate fractures, infection (osteomyelitis), inflammation, and tumors by comparing perfusion and bone remodeling patterns.