CT investigation of chest findings and complications in SARS

Objective: To investigate the role of CT scanning in the diagnosis of severe acute respiratory syndrome (SARS). Methods: One hundred and twelve spiral CT scanning examinations were performed in 82 cases of SARS, which included 106 chest, 5 brain, and 1 abdomen CT examination. CT films were acquired with standard pulmonary and mediastinal window. Results: Of the 82 patient, pulmonary shadows involved bilateral lung field in 66 cases (80.49%) and unilateral lung field in 16(19.51%). The shadows involved 4 to 6 lung fields in 54 cases (66.85%) and the low lung field in 63 (76.83%). The lung CT findings included sub-pleural focal consolidation in 26 cases (31.71%), patchy clouding opacity in 53 (64.63%), large consolidation in 9 (10.98%), ground-glass blurring shadow in 31 (37.80%), small nodules opacity shadow filling in the alveolar cavities in 14 (17.07%), and interstitial changes in 16 (19.51%). There were some specific signs of SARS: (1) The lesions tended to be multiple or bilaterally distributed, and bilateral lower lung field involvement was commonly seen. (2) Imaging findings in lung included sub-pleural focal consolidation shadows, patchy clouding opacity, large consolidation shadows, and ground-glass blurring shadows. There was air bronchogram in the shadows. (3) Opacity small nodule shadows filling in the alveolar cavities. (4) Dynamic follow-up observation on the chest X-ray films and CT films could reveal the rapid progression on the size, amount, and distribution of the lesions (ie, marked dynamic changes within 24 to 48 hours). These findings may suggest the pulmonary changes induced by SARS-CoV. The complications were observed in 6 cases (7.32%) including tuberculosis of the lung and brain, and pneumomediastinum in one case, secondary infection of the lung in 2 cases, pneumothorax in 1 case, pulmonary fungus in 1 case, and empyema of pleura in 1 case. Conclusion: CT examination is a sensitive method for SARS. CT scanning can provide more accurate assessment of the abnormal changes of the lungs and detect the complications of SARS