Kuriyama K, Kadota T, Kuroda C
Dept. of Diagnostic Radiology, Center for Adult Diseases, Osaka Prefecture.
Gan To Kagaku Ryoho. 1990 Nov;17(11):2140-7.
Cancer of the lung is one of the most frustrating yet important challenges facing medicine today. Despite screening programs and education of the public concerning the established link of lung cancer and cigarette smoking, the overall incidence of lung cancer continues to rise. Improved imaging has led to more accurate staging. Expanded treatment has yielded improving survivals of certain specific tumors. Accurate diagnosis and staging of lung cancer is important in detecting therapy and prognosis. Computed tomography (CT) has been established as an important component of the staging process. More recently, applications of magnetic resonance imaging (MRI) are ideally suited to evaluate tumor extent and nodal disease. We reviewed the uses and limitation of CT and MRI. Compared with CT, the relatively low signal in the lung limits the detection of pulmonary nodules and other lung parenchymal diseases, and noise due to motion has been a frequent and significant problem in thoracic MRI. Because of its superior spatial resolution and ability to detect calcification, CT is better than MRI for the detection and evaluation of lung nodules and mediastinal adenopathy when assessing lung cancer. For the detection of mediastinal invasion or lymph node metastases, CT and MRI generally provide similar information. However, volume averaging problems, which may occur on trasaxial CT, can be avoided or clarified using MRI, and nodes can sometimes be more clearly distinguished from vessels using this technique. In the diagnosis of hilar masses or lymphadenopathy, CT and MR provide similar information in the majority of cases, but occasionally MR may more clearly indicate the presence or absence of a mass. Because of superb vascular imaging capability (without the need for exogenous contrast agents), exquisite soft tissue contrast, the ability to image the chest directly in multiple planes, and the potential to characterize certain tissues, MRI appears to be superior to CT in defining the extent of chest-wall invasion. In general, CT is superior to MRI as an all-around tool for imaging the wide range of thoracic abnormalities that can be present in patients with lung cancer. Limited availability, and longer examination time of MRI compared with CT has restricted the use of thoracic MRI. If MRI is used selectively as a secondary imaging study to answer specific questions raised or unanswered by CT, its value can be optimized.
肺癌是当今医学面临的最令人沮丧却又十分重要的挑战之一。尽管开展了筛查项目并对公众进行了关于肺癌与吸烟之间既定联系的教育，但肺癌的总体发病率仍在持续上升。成像技术的改进使得分期更加准确。治疗方法的扩展提高了某些特定肿瘤患者的生存率。肺癌的准确诊断和分期对于检测治疗效果及判断预后很重要。计算机断层扫描（CT）已成为分期过程的重要组成部分。最近，磁共振成像（MRI）的应用非常适合评估肿瘤范围和淋巴结病变。我们回顾了CT和MRI的用途及局限性。与CT相比，肺部相对较低的信号限制了肺结节和其他肺实质疾病的检测，并且运动产生的噪声一直是胸部MRI中常见且严重的问题。由于CT具有 superior spatial resolution 和检测钙化的能力，在评估肺癌时，对于肺结节和纵隔淋巴结肿大的检测及评估，CT优于MRI。对于纵隔侵犯或淋巴结转移的检测，CT和MRI通常提供相似的信息。然而，轴向CT可能出现的容积平均问题，使用MRI可以避免或得到更清晰的显示，并且有时使用该技术可以更清楚地将淋巴结与血管区分开来。在肺门肿块或淋巴结肿大的诊断中，大多数情况下CT和MR提供相似的信息，但偶尔MR可能更清楚地显示肿块的存在与否。由于具有出色的血管成像能力（无需外源性对比剂）、精细的软组织对比度、能够在多个平面直接对胸部进行成像以及对某些组织进行特征性描述的潜力，MRI在确定胸壁侵犯范围方面似乎优于CT。总体而言，作为对肺癌患者可能出现的各种胸部异常进行成像的全面工具，CT优于MRI。MRI的可用性有限，且与CT相比检查时间更长，这限制了胸部MRI的使用。如果将MRI作为二级成像检查选择性地用于回答CT提出或未解决的特定问题，其价值可以得到优化。
