Effects of radiation on bone.
Ionizing radiation produces its deleterious biologic effects by both direct (DNA strand breaks) and indirect processes (formation of free oxygen radicals). Mitotically active cells are more susceptible to the detrimental effects of ionizing radiation. These effects are most severe locally within the treatment field but can also occur systemically, possibly reflecting hormonal influences and inflammatory cytokine mediators. Specific bone complications of radiation include osteopenia, growth arrest, fracture and malignancy. Some of these complications, such as osteopenia, are reversible and severity is dose dependent. Insufficiency fractures are a common complication after radiation therapy and generally affect those bones under most physiologic stress and with the highest ratio of trabecular to cortical bone. Familiarity with the radiographic appearance of irradiated bone, including computed tomography (CT) and magnetic resonance imaging (MRI), will improve image interpretation and facilitate accurate diagnosis.
Department of Diagnostic Imaging and Therapeutics, University of Connecticut Health Center, 263 Farmington Avenue, Farmington, CT, 06030-2802, USA.
Rafael
R
Pacheco
Harlan
H
Stock
D017209:Apoptosis / Q000528:radiation effects; D001851:Bone Diseases, Metabolic / Q000453:epidemiology*; D001859:Bone Neoplasms / Q000453:epidemiology*; D001842:Bone and Bones / Q000473:pathology* / Q000528:radiation effects*; D049109:Cell Proliferation / Q000528:radiation effects; D050723:Fractures, Bone / Q000453:epidemiology*; D006801:Humans; D009381:Neoplasms, Radiation-Induced / Q000453:epidemiology; D010012:Osteogenesis / Q000528:radiation effects; D011829:Radiation Dosage; D012307:Risk Factors