Reversed halo sign in pulmonary infarction with tumor emboli: a case report.

We describe the case of a 79-year-old woman with pulmonary infarction due to tumor emboli whose high-resolution CT (HRCT) scan demonstrated the reversed halo sign. The patient had gastric cancer and died because of cancer-related cerebral infarction. On autopsy, the central ground-glass area of the reversed halo sign on HRCT corresponded to pulmonary edema associated with alveolar septal capillary metastasis, whereas the peripheral ring-like consolidation consisted of a hemorrhagic infarct with tumor emboli. The present case is important because a detailed pathologic correlation with this unique HRCT appearance was revealed.