Figure 4a. SARS-related lesion with shifting. Serial radiographic changes in a 26-year-old woman with SARS. (a) Frontal chest radiograph obtained 8 days after fever onset shows a large air-space opacity (arrows) confined to the right middle lung. (b) Follow-up chest radiograph obtained 5 days later shows marked regression of the original air-space opacity (solid arrow) but development of a laterally located new opacity (open arrow). The patient recovered 6 days later.