Rathbun S W, Raskob G E, Whitsett T L
Department of Medicine, University of Oklahoma Health Sciences Center, Oklahoma City 73190, USA.
Ann Intern Med. 2000 Feb 1;132(3):227-32. doi: 10.7326/0003-4819-132-3-200002010-00009.
To determine the sensitivity and specificity of helical computed tomography (CT) for the diagnosis of pulmonary embolism and to determine the safety of withholding anticoagulant therapy in patients who have clinically suspected pulmonary embolism and negative results on helical CT.
The MEDLINE database was searched for all reports published from 1986 to October 1999 that evaluated the use of helical CT for the diagnosis of pulmonary embolism. Bibliographies of the retrieved articles were cross-checked to identify additional studies.
All prospective English-language studies were selected. Retrospective studies, review articles, and case reports were excluded, and 5 of the 20 identified articles were excluded. The scientific validity of the remaining 15 articles was assessed.
Two of the authors used a priori, pre-defined criteria to independently assess each study. A third author resolved disagreements by adjudication. The pre-defined criteria were inclusion of a consecutive series of all patients with suspected pulmonary embolism, inclusion of patients with and those without pulmonary embolism, a broad spectrum of patient characteristics, performance of helical CT and pulmonary angiography (or an appropriate reference test) in all patients, and independent interpretation of the CT scan and pulmonary angiogram (or reference test). Specific data on sensitivity and specificity and the associated 95% CIs were recorded when available.
No study met all of the predefined criteria for adequately evaluating sensitivity and specificity. The reported sensitivity of helical CT ranged from 53% to 100%, and specificity ranged from 81% to 100%. In no prospective study was anticoagulant therapy withheld without further testing for venous thromboembolism in consecutive patients with suspected pulmonary embolism. One prospective study reported the outcome of selected patients with negative results on helical CT who did not receive anticoagulant therapy.
Use of helical CT in the diagnosis of pulmonary embolism has not been adequately evaluated. The safety of withholding anticoagulant treatment in patients with negative results on helical CT is uncertain. Definitive large, prospective studies should be done to evaluate the sensitivity, specificity, and safety of helical CT for diagnosis of suspected pulmonary embolism.
确定螺旋计算机断层扫描（CT）诊断肺栓塞的敏感性和特异性，并确定对于临床怀疑肺栓塞但螺旋CT结果为阴性的患者停用抗凝治疗的安全性。
检索MEDLINE数据库中1986年至1999年10月发表的所有评估螺旋CT用于诊断肺栓塞的报告。对检索到的文章的参考文献进行交叉核对以识别其他研究。
选择所有前瞻性英文研究。排除回顾性研究、综述文章和病例报告，在识别出的20篇文章中排除了5篇。评估其余15篇文章的科学有效性。
两位作者使用预先定义的标准独立评估每项研究。第三位作者通过裁决解决分歧。预先定义的标准包括纳入一系列连续的所有疑似肺栓塞患者、纳入有和没有肺栓塞的患者、广泛的患者特征、对所有患者进行螺旋CT和肺血管造影（或适当的参考检查）以及对CT扫描和肺血管造影（或参考检查）进行独立解读。如有可用，记录关于敏感性、特异性及相关95%可信区间的具体数据。
没有研究符合充分评估敏感性和特异性的所有预先定义标准。报告的螺旋CT敏感性范围为53%至100%，特异性范围为81%至100%。在任何前瞻性研究中，对于连续的疑似肺栓塞患者，在未进一步检测静脉血栓栓塞的情况下均未停用抗凝治疗。一项前瞻性研究报告了螺旋CT结果为阴性且未接受抗凝治疗的部分患者的结局。
螺旋CT在肺栓塞诊断中的应用尚未得到充分评估。螺旋CT结果为阴性的患者停用抗凝治疗的安全性尚不确定。应开展明确的大型前瞻性研究以评估螺旋CT诊断疑似肺栓塞的敏感性、特异性和安全性。
