造影剂注入法三维肺动脉MRA用于诊断肺癌浸润肺动脉的初步临床经验

Diagnosis of invasion of pulmonary artery in lung carcinoma Initial experience on contrast-enhanced three-dimensional pulmonary MR angiography

目的：介绍造影剂注入法三维肺血管MRA（3D－MRPA）技术在诊断肺癌浸润肺动脉上的应用经验，初步认识此项技术的临床价值。材料和方法：肺癌4例。Cd－DTPA0．2mmol／kg静注后，应用高性能MR扫描系统，闭气下摄取24层肺血管SPGR序列连续冠状断面像，用时27秒。再重复同样扫描，分别获得肺动脉期相与支气管动脉期相。最后，以最大强度投影法（MIP）制成3D－MRPA。结果：4例肺癌显示出3种MRPA表现：肺动脉受累、可疑肺动脉受累与肺动脉无受累。可疑肺动脉受累，病例手术证实为粘连，MRPA的原始图像显示肿瘤与血管相切密切，血管内腔通畅，但管壁轻微受压变形。结论：造影法三维MRPA可以评价肿瘤浸润肺动脉。

Objective: Introducing the experience of contrast enhanced three dimensional pulmonary MR angiography(MRPA) on diagnosis of invasion of pulmonary artery in lung carcinoma and initially recognizing the clinical value of this technique. Materials and Methods:Four patients with lung careinoma were scanned after intravenous bolus injection of 0. 2mmol/kg Gd - DTPA, applying superior quality MRscaner, coronal SPGR images of 24 slices was acquired by hold - breath during 27 seconds. Same scan was performed immediately again. Theimages of pulmonary and bronchial artery Stage were acquired separately .Three dimensional MRPA was reconstructed by using maximum intensity projection technique. Results:Three types of MRPA finding in four patients with lung carcinoma were showed: invasion, suspected invasion and non - invasion of pulonary artery. Adhesion was confirmed in the case of suspected invasion, but its original images of MRPAshowed that tumor connected closely with pulmonary artery, inner cavity of blood vessel unobstructed and the wall of blood vessel deformedslightly. Conclusion: contrast enhanced three dimensiondal MRPA may be applied for evaluating invasion of pulmonary artery in lung carcinoma.