Cold Defect on Bone Scan

• Radiation: Tends to occur at least 2 months following a dose of at least 20 Gy.
• Early infarction: For example, following trauma or in patients with sickle cell disease.
• Neoplasm: For example, multiple myeloma/plasmocytoma, renal and thyroid cancer metastases, chordoma.
• Osteomyelitis: Especially in children. Edema and increased local pressure (due to subperiosteal or intraosseus pus) may decrease the blood flow and tracer uptake early in the course of infection.
• Hemangioma: Most commonly isointense to surrounding bone, but can be photopenic or hyperintense.
• Artifact: Barium in gastrointestinal tract, hardware, metallic objects (belt buckle, jewelery, etc.).

Stupid Mnemonic: Think of A Rhino punching a cold defect into a bone: Artifact, Radiation, Hemangioma, Infarction (early), Neoplasm, Osteomyelitis.

References

• Greyson ND, Kassel EE. Serial bone-scan changes in recurrent bone infarction. J Nucl Med. 1976 Mar;17(3):184-6.
• Rehm PK, Delahay J.Epiphyseal photopenia associated with metaphyseal osteomyelitis and subperiosteal abscess. J Nucl Med. 1998 Jun;39(6):1084-6.
• Sopov V, Liberson A, Gorenberg M, Groshar D. Cold vertebrae on bone scintigraphy. Semin Nucl Med. 2001 Jan;31(1):82-3.