SARS的胸部CT早期表现

目的 探讨SARS胸部CT早期表现及其在早期诊断中的作用。方法40例符合临床诊断标准的SARS患者在发病后1周内进行胸部CT扫描，同时行常规计算机摄影(CR)胸片检查。回顾性分析这些胸部平片和CT图像，重点观察胸部有无异常表现，并对胸部CT异常阴影的数目、位置、密度、形态和分布进行分析。结果 胸部CT扫描发现40例SARS患者均有不同程度的肺部异常阴影。而CR胸片未见异常者9例，可疑者6例，明确有异常者25例。SARS肺部CT异常表现主要是不同程度的肺部炎性浸润，病灶密度低、不均匀，以磨玻璃样改变多见，为25例(62．5％)(此类改变胸片容易漏诊)，实变11例(27．5％)，两者均有4例(10％)。70．0％的病例(28例)只有l～2个病灶，30．0％的病例(12例)有3个以上病灶或两肺多发。病灶彤态以斑片状和球形为常见，占82．5％(33例)，也可累及整个肺段(4例，10．0％)或表现为坠积性肺炎样(3例，7．5％)。病灶常位于肺的周边部位(28例，70％)，同时累及周边和中心者11例(17．5％)。25．0％的病例(10例)出现支气管气像。结论胸部CT扫描能早期发现SARS患者肺部异常阴影，明显优于胸片。SARS患者肺部CT异常早期表现有其特点，但非特异性。因此，胸部CT检查在SARS病人的早期诊断和鉴别诊断中有重要作用。

Early appearance of SARS on chest CT scan

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