Objective: To evaluate the value of reversed halo sign( RHS) in the diagnosis and differential diagnosis of lung diseases by chest CT. Methods: Clinical manifestation,thoracic CT features and the final diagnosis of 32 patients with reversed halo sign of chest CT had been analyzed retrospectively. Results: There were 21 cases of non-infectious pulmonary diseases: 9 cases of lung adenocarcinoma,5 organizing pneumonia( 4 cases of cryptogenic organizing pneumonia and 1 case of atypical organizing pneumonia by pathogen infection),2 pulmonary embolism,1 pulmonary Wegener granuloma,1 pulmonary eosinophilia pneumonia,1 radiofrequency treatment after lung cancer,1 radiotherapy after lung cancer and 1 sjogren's syndrome. There were 11 cases of infectious pulmonary diseases: 7 cases of tuberculosis and 4 pulmonary invasive fungal diseases. There were 9 cases of single lung lesions( 28. 1%) and 23 cases of multiple pulmonary lesions( 71. 9%). Conclusion: RHS can be found in many kinds of lung diseases and it has no characteristic in the diagnosis of lung diseases.
reversed halo sign