Abstract No. 380 - Review of techniques for percutaneous lymphangiography and thoracic duct cannulation for treatment of chylothorax

Abstract

There are multiple methods used to access the thoracic duct in attempt for embolization in the setting of traumatic or spontaneous chylous leak. We will review the indications and technique in three differing methods; traditional pedal lymphangiography, intranodal lymphangiography and retrograde transvenous cannulation. The prevalence of thoracic duct injury is 0.5-2.0% following major thoracic or neck surgery. Thoracic duct injury leading to unremitting chylothorax can have a mortality rate of 25-50%. Patients with thoracic duct leaks who fail conservative management, have been historically treated with surgery. However the thoracic duct can be difficult to identify by the surgeon. Lymphangiography serves two purposes, first to identify the leak and evaluate the anatomic course of the thoracic duct, and second to provide access for percutaneous treatment. Traditional pedal lymphangiography involves cannulating lymphatic ducts in the foot and injecting Ethiodized oil to opacify the cisterna chyli and thoracic duct. This method requires substantial procedure time for the contrast to travel from the foot to thoracic duct. Direct intranodal injection involves ultrasound guided puncture of the inguinal lymph nodes into which Ethiodized oil is injected. This method bypasses the lower extremity lymphatics. In both of these techniques, once the thoracic duct is opacified, it can be cannulated percutaneously in the upper abdomen under fluoroscopic guidance. Retrograde cannulation of the thoracic duct involves transvenous cannulation where the duct drains to the systemic circulation, usually at the confluence of left internal jugular and subclavian veins. The presence of a valve makes this technique challenging. Given the high mortality rate and difficulty of surgical treatment, percutaneous lymphangiography with thoracic duct embolization remains an important treatment option for chylothorax. Knowledge of various techniques can increase success of thoracic duct cannulation and embolization.