纵隔血管畸形的CT表现

CT Demonstrations of Vascular Malformation in the Mediastinum

目的:分析纵隔血管畸形的影像表现,与病理对照,旨在提高对纵隔血管畸形影像表现的认识。方法:回顾性分析4例经手术病理证实的纵隔血管畸形影像表现。由影像科及病理科医师共同阅片,将影像表现与病理学进行对照分析。结果:海绵状血管瘤3例,血管淋巴管瘤1例。位于前纵隔3例,后纵隔1例。1例胸片未显示病变,3例胸片表现为单侧纵隔肿块,均未见钙化灶。平扫1例,平扫加增强1例,增强2例。2例平扫密度均匀,边缘规整,1例显示多发静脉石。1例增强扫描表现为多个结节融合,未见明确强化;1例病变边缘见斑片状强化;1例分别经双侧肘静脉注射对比剂先后行两次增强扫描:右肘静脉注射对比剂,动脉期肿物内未见强化,延迟期肿物中心见团块状强化;第二天再行左肘静脉注射对比剂,动脉期肿物中心见团块状强化;多平面图像重组清楚显示肿物的引流静脉来源于左头臂静脉发出的分支。结论:纵隔血管畸形多位于前纵隔,静脉石具有特征性,增强CT扫描可提供重要的诊断信息。

Objective：To review chest radiographs and CT scans of 4 patients with mediastinal vascular malformation and correlate them with their pathologic findings in order to improve our understanding of the imaging features. Methods： The imaging features of 4 patients with pathology proved vascular malformation of mediastinum were reviewed. The imaging findings were studied retrospectively and correlated with those of pathology. Results： The locations of mediastinal vascular malformations of the four cases were as follows：three masses were in the anterior me diastinum and one in the posterior mediastinum. On chest radiographs, three masses were sharply marginated with smooth borders. No calcified loci were identified in any case. On unenhanced CT, two cases manifested themselves as well-marginated masses with homogeneous attenuation. Multiple phleboliths were identified in one case. Contrast-enhanced CT scans were available in three cases. During the arterial phase,one mass remained hypodense,and one mass exhibited peripheral inhomogeneous enhancement. A double phase enhanced CT study was performed with an intravenous contrast bolus delivered via the right antecubital vein. In the pulmonary arterial phase,there was no central increased attenuation in the mass. However,the systemic venous phase revealed central dilated vessel structures in the mass. Afterwards, another double phase enhanced CT was done via the left antecubital vein the next day. Undiluted contrast was deposited in the mass in the pulmonary arterial phase, and more ho mogenously diluted iodine entered the mass in the systemic venous phase. Multiplanar reconstruction showed that the contrast directly entered the mass via a large branch downward from the left innominate vein. Conclusion： Mediastinal vascular malformation involves in the anterior mediastinum more frequently than in the middle or posterior. Phlebolith is a specific finding of the mediastinal vascular malformation at CT scans. Contrast enhanced CT scans can offer important diagnostic in formation.