严重急性呼吸综合征(SARS)早期胸部影像学表现

The early radiographic appearances of severe acute respiratory syndrome(SARS)

目的:探讨SARS胸部影像的早期变化。方法:观察24例符合SARS临床诊断标准的患者在发病3天之内的胸部平片及CT扫描结果。回顾性分析这些胸部平片及CT图像,观察、对比平片及CT图像1～3天内异常征象的发展,并对异常改变包括病变的数目、位置、大小和分布加以分析。结果:发病当天就诊并摄胸部平片的患者,胸部改变均为阴性,而CT扫描显示均为阳性改变。第二天摄片,大部分胸片为阳性改变,部分为可疑,少数仍为阴性改变。而CT改变较当日明显增大、增多。第三日摄片,胸片大部分为阳性改变。早期SARS病变胸部影像改变为小斑片状阴影,密度小而淡,约1～2cm,极易漏诊,随病变发展,CT出现棉团样改变。结论:根据SARS病情发展快、变化快的特点,早期诊断要定期复查胸片,时间不宜过长,最好每天复查,有条件应做胸部CT扫描。

Objective:To determine the early radiographic appearances of severe acute respiratory syndrome (SARS).Ma te-rials and Methods:Twenty-four cases of SARS consistent with criteria from the Chinese Ministry of Health were included in this study.Their chest X-rays and CT images within3days after onset were retrospectively reviewed.The radiographic ap-pearance was compared with that of CT,the number,location,size and distribution of the lesions in the lung were further assessed.Results:Chest radiographs taken at the time of onset of symptoms were normal,while CT was positive.On the sec-ond day,most of the chest radiographs were positive,some were equivocal,and few were normal.CT showed increase in size and number of lesions compared to the previous day.On the third day,almost all chest radiographs were positive.The early signs of SARS were small patchy opacities,about 1～2cm in diameter,therefore were easily missed on radiographs.They could develop to big ball-like opacities.Conclusion:Since the radiographic appearance of SARS changes fast,follow-up chest radio-graphs should be taken daily or CT scan should be performed to assist in early diagnosis.