Rationale: Outcomes of interventional lymphangiographic treatment of nontraumatic chylous pleural effusions using traditional approaches have been highly variable. Recent advances in lymphatic imaging have revealed variations in underlying pathophysiology, enabling improved targeting of therapeutic interventions. Objectives: To assess outcomes of an algorithm for management of nontraumatic chylous pleural effusions based on advanced magnetic resonance (MR) identification of various abnormalities in the thoracoabdominal lymphatic network that give rise to chylothorax. Methods: Novel lymphatic MR imaging was performed in 52 patients aged 11-89 years. Three distinct pathophysiological patterns were found: 1) abnormal pulmonary lymphatic flow from the thoracic duct only; 2) abnormal pulmonary lymphatic flow from retroperitoneal lymphatic networks with or without involvement of the thoracic duct; and 3) chylous ascites presenting as chylous pleural effusion. Lymphatic interventions were individualized to the underlying pathophysiological patterns. Results: In 41/52 (79%) patients, imaging revealed abnormal pulmonary lymphatic flow from the thoracic duct and/or retroperitoneal lymphatic networks. Thoracic duct embolization and/or interstitial embolization of retroperitoneal lymphatic resulted in resolution of chylothorax in this group in 38/41 (93%) of those patients. Five patients experienced grade 1 or 2 complications. One patient succumbed to postoperative stress-induced cardiomyopathy and pulmonary embolism. Chylous ascites was the cause of chylothorax in 11/52 (21%) patients. Eight chose to undergo interventions for chylous ascites with clinical success in 6/8 (75%). Conclusions: Application of magnetic resonance imaging-guided intervention algorithm resulted in successful control of nontraumatic chylothorax in 93% patients with abnormal pulmonary lymphatic flow. Appropriate treatment of chylous ascites presenting as a pleural effusion requires systematic evaluation and diagnosis prior to potential treatments.
Keywords: MRI; embolization; lymphatics; nontraumatic chylothorax; thoracic duct.