肺韧带对下胸部疾病螺旋CT表现的影响及其解剖学基础

Effects of the pulmonary ligament on helical CT appearances of lower thoracic disease: anatomic-radiologic study

目的 明确肺韧带对下胸部疾病螺旋CT表现的影响及其解剖学基础。方法 观察4例尸体横断面标本的肺韧带形态及附着点。并搜集经临床和病理证实的下胸部疾病 5 7例 ,采用螺旋CT增强扫描。在螺旋CT图像上 ,观察肺韧带对下胸部疾病的影响及其影像学表现特征 ,结合实体标准 ,分析其解剖学基础。结果 尸体横断面标本上 ,肺韧带位于下肺静脉下方 ,为连接肺下叶与纵隔的胸膜反褶 ,右侧附着于食管 ,左侧附着于食管或降主动脉。螺旋CT上 ,40例胸腔积液和 7例气胸压迫肺下叶致肺不张 ,肺韧带固定肺下叶 ,使压缩的肺下叶不向上达肺门 ;40例胸腔积液中 ,肺韧带将胸腔积液分隔成前、后两部分 ;7例下叶肺癌及 3例炎性病变直接累及肺韧带 ,使其呈结节状或鸟嘴状增厚。结论 肺韧带固定肺下叶 ,影响下胸部疾病 (肺不张、胸腔积液和气胸等 )的影像学表现 ;

Objective To determine how the pulmonary ligament affects the helical CT appearances of the lower thoracic disease on the basis of the anatomic findings. Methods Four cadavers were cut transversely, with the section thickness of 11.3-13.4 mm. 57 patients with the lower thoracic disease were scanned using Somatom Plus 4, with administration of intravenous contrast material. The correlation of the anatomic findings of the pulmonary ligament and the helical CT appearances of the lower thoracic disease was evaluated. Results On cadaver sections, the right pulmonary ligament attached the lower lobe of the right lung to the esophagus, while the left ligament attached the lower lobe of the left lung to the esophagus or the descending aorta. In 40 pleural effusion and 7 pneumothorax cases, the pulmonary ligament tethered the medial aspect of the collapsed lower lobe and limited the shift of the lower lobe. In 40 pleural effusions, the ligament divided the medial pleural space into an anterior and a posterior compartment. The ligament showed thickness due to the invasion of the lesions of lower lobe including 7 tumors and 3 inflammatory diseases. Conclusion The pulmonary ligament can affect the helical CT appearances of the lower thoracic disease, such as lobe collapse, pleural effusion and pneumothorax; while the intraparenchymal and mediastinal abnormality can extend into the pulmonary ligament.