Table 1.
Granulomatous diseases.
Table 2.
Non-granulomatous diseases.
Fig 1.
A,B. A 26-year-old male diagnosed with tuberculosis pathologically. HRCT showed reversed halo sign(1-A,white arrow), and the CT-guided lung biopsy of the “ring” showed granulomas with caseating necrosis(1-B,black arrow, HE stain, 400x magnification).
Fig 2.
A, B. A 37-year-old male diagnosed with tuberculosis pathologically. HRCT showed reversed halo sign(2-A,white arrow), and the CT-guided lung biopsy of the “ring” showed granulomas with caseating necrosis(2-B,black arrow, HE stain, 100x magnification).
Fig 3.
A, B. A 52-year-old female diagnosed with tuberculosis by smear positive sputum(at the third time of sputum smear). HRCT showed reversed halo sign(3-A,white arrow), and the CT-guided lung biopsy of the “ring” showed granulomas (3-B,black arrow, HE stain, 200x magnification).
Fig 4.
A, B. A 72-year-old male diagnosed with tuberculosis pathologically. The HRCT showed reversed halo sign(4-A,white arrow), and the CT-guided lung biopsy of the “ring” showed granulomas with caseating necrosis(4-B,black arrow, HE stain, 100x magnification).
Fig 5.
A, B. A 54-year-old female diagnosed with sarcoidosis pathologically. The HRCT showed reversed halo sign(5-A,white arrow) and bilateral hilar lymph nodes enlargement, and the CT-guided lung biopsy of the “ring” showed multiple non-caseating necrotic granulomas(5-B, black arrows, HE stain,400x magnification), which was consistent with the bronchoscopic mucosa biopsy.
Fig 6.
A, B. A 55-year-old female diagnosed with sarcoidosis pathologically. The HRCT showed reversed halo sign(6-A,white arrow) and bilateral hilar lymph nodes enlargement, and the bronchoscopic mucosa biopsy showed multiple non-caseating necrotic granulomas(6-B, black arrows, HE stain,200x magnification).
Fig 7.
A, B. A 50-year-old female diagnosed with sarcoidosis pathologically. The HRCT showed reversed halo sign(7-A,white arrow), and the CT-guided transthoracic lung biopsy of the focal “ring” showed non-caseating necrotic granulomas(7-B, black arrow, HE stain, 200x magnification).
Fig 8.
A, B, C. A 55-year-old male diagnosed with pulmonary cryptococcosis pathologically. The HRCT presented with a mass rounded by halo sign at the right lower lung at first(8-A,white arrow), and the CT-guided transthoracic lung biopsy of the focal zone showed destructed alveolar infiltrated with granulomas and inflammatory cells, Periodic acid-Schiff (PAS) stain(+), methenamine silver stain (+), AFB(-), (8-B, black arrows, PAS stain showed the red-stained capsules of the cryptococcus, 400x magnification). After 4 weeks of fluconazole therapy, the follow-up low dose CT showed reversed halo sign in the same location as the previous lesion, which resulted from the central part absorption that made the residual lesion a ring shape (8-C).
Fig 9.
A, B. A 45-year-old female diagnosed with GPA pathologically. The HRCT showed reversed halo sign(9-A,white arrow), and the CT-guided transthoracic lung biopsy of the focal “ring” showed necrotizing granulomatous inflammation(9-B,black arrows, HE stain, 200x magnification).
Fig 10.
A, B, C. A 44-year-old female diagnosed with COP pathologically. The HRCT showed reversed halo sign of the left upper lobe(10-A) and the left lower lobe(10-B), and the CT-guided transthoracic lung biopsy of the “ring” of reversed halo sign in the left lower lobe showed intraluminal organizing fibrosis in distal air spaces(10-C,black arrow, HE stain, 200x magnification).
Fig 11.
A, B. A 50-year-old female diagnosed with COP pathologically. The HRCT showed reversed halo sign of the left upper lobe(11-A), and the CT-guided transthoracic lung biopsy of the focal “ring” showed intraluminal organizing fibrosis in distal air spaces(11-B, black arrow, HE stain, 200x magnification).
Fig 12.
A, B. A 49-year-old female diagnosed with COP pathologically. The HRCT showed reversed halo sign of the right upper lobe(12-A), and the CT-guided transthoracic lung biopsy of the focal “ring” showed intraluminal organizing fibrosis in distal air spaces(12-B, black arrows, HE stain, 200x magnification).
Fig 13.
A, B, C. A 73-year-old female diagnosed with COP pathologically. The HRCT showed reversed halo sign of the right upper lobe(13-A) and the right lower lobe(13-B), and the CT-guided transthoracic lung biopsy of the focal “ring” of reversed halo sign in the right lower lobe showed intraluminal organizing fibrosis in distal air spaces(13-C, black arrow, HE stain, 200x magnification).
Fig 14.
A, B. A 65-year-old male diagnosed with low differentiated adenocarcinoma pathologically. The HRCT showed reversed halo sign of the right lower lobe(14-A), and the CT-guided transthoracic lung biopsy of the focal “ring” showed nested tumor tissue with necrosis, and no normal alveolar structure was found (14-B, HE stain, 100x magnification).
Fig 15.
A, B. A 75-year-old male diagnosed with low differentiated adenocarcinoma pathologically. The HRCT showed reversed halo sign of the left upper lobe(15-A), and the CT-guided transthoracic lung biopsy of the focal “ring” showed diffused infiltration of tumor cells with necrosis, and no normal alveolar structure was found (15-B, HE stain, 100x magnification). The immunohistochemical staining: TTF-1(+), ALK(+), CK7(+), Napsin(+), CK5(+).
Fig 16.
A, B, C. A 42-year-old male diagnosed with adenocarcinoma by pleural effusion, the HRCT showed a mass in the right upper lobe(16-A) and adenocarcinoma cells were found in the pleural effusion smear with the background the lymphocytes(16-B, black arrow, 200x magnification), no chemotherapy but just pleural fluid drainage was performed, and 6 weeks later the follow-up CT scan showed reversed halo sign(16-C).