Department of Radiology, St. Vincent's University Hospital, Elm Park, Dublin 4, Ireland.
J Cardiovasc Comput Tomogr. 2009 Nov-Dec;3(6):361-71. doi: 10.1016/j.jcct.2009.10.007. Epub 2009 Oct 30.
Cardiac computed tomography (CT) has evolved into an effective imaging technique for the evaluation of coronary artery disease in selected patients. Two distinct advantages over other noninvasive cardiac imaging methods include its ability to directly evaluate the coronary arteries and to provide a unique opportunity to evaluate for alternative diagnoses by assessing the extracardiac structures, such as the lungs and mediastinum, particularly in patients presenting with the chief symptom of acute chest pain. Some centers reconstruct a small field of view (FOV) cropped around the heart but a full FOV (from skin to skin in the area irradiated) is obtainable in the raw data of every scan so that clinically relevant noncardiac findings are identifiable. Debate in the scientific community has centered on the necessity for this large FOV. A review of noncardiac structures provides the opportunity to make alternative diagnoses that may account for the patient's presentation or to detect important but clinically silent problems such as lung cancer. Critics argue that the yield of biopsy-proven cancers is low and that the follow-up of incidental noncardiac findings is expensive, resulting in increased radiation exposure and possibly unnecessary further testing. In this 2-part review we outline the issues surrounding the concept of the noncardiac read, looking for noncardiac findings on cardiac CT. Part I focused on the pros and cons for and against the practice of identifying noncardiac findings on cardiac CT. Part II illustrates the imaging spectrum of cardiac CT appearances of benign and malignant noncardiac pathology.
心脏计算机断层扫描（CT）已发展成为一种评估特定患者冠状动脉疾病的有效成像技术。与其他非侵入性心脏成像方法相比，它有两个明显的优势：其一，能够直接评估冠状动脉；其二，通过评估肺和纵隔等心脏外结构，为评估其他诊断提供独特机会，特别是在以急性胸痛为主诉的患者中。一些中心会重建一个围绕心脏的小视野（FOV），但在每个扫描的原始数据中都可以获得完整的 FOV（从受照射区域的皮肤到皮肤），因此可以识别出临床相关的非心脏发现。科学界的争论集中在是否需要这种大 FOV。对非心脏结构的检查提供了做出其他诊断的机会，这些诊断可能与患者的表现有关，或者可以发现重要但临床无症状的问题，如肺癌。批评者认为，活检证实的癌症发病率低，而且对偶然发现的非心脏疾病的随访费用昂贵，这会导致辐射暴露增加，可能需要进一步进行不必要的检查。在这篇由两部分组成的综述中，我们概述了围绕心脏 CT 非心脏阅读概念的问题，即在心脏 CT 上寻找非心脏发现。第一部分重点讨论了在心脏 CT 上识别非心脏发现的利弊。第二部分说明了心脏 CT 对良性和恶性非心脏病变的影像学表现范围。
