目的　探讨ECT对SARS患者应用过大剂量类固醇激素治疗愈后引起骨坏死的早期诊断价值。方法　对 4例SARS愈后患者进行ECT、X线平片和MRI的骨坏死检查 ,对比分析三种检查方法对骨坏死的诊断价值。结果　 4例病例在ECT及MRI上均能显现同一解剖部位早期骨坏死改变 ,并且先于X线平片。结论　ECT及MRI均能提供早期骨坏死的诊断。ECT可以在一次检查中发现全身多处病变。 Objective To investigate the early diagnosis of osteonecrosis induced by ECT in patients with severe acute respiratory syndrome (SARS) treated with overdose of steroid hormone. Methods Four patients with SARS were diagnosed as osteonecrosis by ECT, X-ray and MRI. The diagnostic value of the three methods in diagnosis of osteonecrosis was compared. Results Four cases showed early osteonecrosis of the same anatomical region on both ECT and MRI, and were preceded by X-ray plain film. Conclusion Both ECT and MRI can provide early diagnosis of osteonecrosis. ECT can be found in a check multiple lesions throughout the body.