Early appearance of SARS on chest CT scan / 中华放射学杂志

ABSTRACT

Objective To evaluate the early appearance of SARS on chest CT scan and its role in the early diagnosis Methods Forty cases of SARS in keeping with the criteria of the Ministry of Health had chest CT scans within 7 days of onset of symptoms, and CR chest X-ray films were available as well These chest X-rays and CT images were retrospectively reviewed to determine if there were any abnormalities on the images The lesions on the chest CT images were then further analyzed in terms of the number, location, size, and density Results Positive abnormalities on chest CT scans were revealed in all 40 SARS cases Positive findings on CR chest films were showed in only 25 cases, equivocal in 6, and normal in 9 cases The main abnormalities seen on CT and X-rays were pulmonary infiltrations varied markedly in severity 70% cases had 1 or 2 lesions on chest CT scan, 30% cases had 3 or more lesions The lesions seen on chest CT scan tended to be ground-glass opacification, sometimes with consolidation which was very faint and inhomogeneous, easily missed on chest X-rays Typically the lesions were located in the periphery of the lung, or both central and peripheral lung, but very rare in a pure central location They were commonly in the shape of patch or ball Conclusions Chest CT scan is much more sensitive in detecting the lesions of the lung in SARS The early appearance of SARS on chest CT scan is characteristic but non-specific, indicating that chest CT scan plays a very important role in the early diagnosis and differential diagnosis of SARS