[Thoracic duct collaterals of lymphatic and pulmonary origin. Anatomy and chylothorax after pulmonary surgery].

Dye injection of lung segments reveals the existence of lymphatic drainage of the lungs generally into cervical venous confluents and more rarely into the arch of the thoracic duct in the neck and also occasionally into the thoracic duct in the mediastinum. Direct drainage of the lymph into the thoracic duct was observed in 10 cases out of a series of 589 injections of lung segments in adult cadavers. In one half of cases, the thoracic duct was injected from the left suprabronchial lymph node chain, the origin of the left recurrent chain, and in one quarter of cases from the lateral anteroposterior right major azygos and left azygo-aortic lymph node chains, not recognised by the classical authors. More rarely, direct lymphatic collaterals drained certain segments of the lower lobes into the thoracic duct via the triangular ligament. Analysis of cases of chylothorax occurring after lung resection and observed in the authors' department or in the literature reveals that most of them can be attributed to a chyle leak from one of these pulmonary lymph collaterals. These pathways are probably also involved in the development of medical or idiopathic chylothorax.