Postmortem Retrograde Contrasted Infusion in Thoracic Duct Outflow: Imaging Effectiveness Analysis

Background Thoracic duct (TD) anomaly can be quite variable and dangerous in surgical interventions in the neck region as there are numerous variations in its formation and topography. This highlights the importance of full knowledge about the TD and its anatomical variations. Thus, it is important to emphasize that the lack of anatomical-clinical knowledge or surgical skill during an intervention can significantly hamper successful results. The present study aimed to perform radiopaque contrast infusion into the TD of intact cadavers, either formalinized or refrigerated, to evaluate possible lymphatic architecture patterns via reverse lymphography. Methodology TD dissection was performed on 13 cadaveric specimens. After isolating the lymphatic vessel, it was cannulated with an nº 4 urethral probe fixed with cordonnet cotton. Then, a 10 mL syringe was attached to the urethral probe and the radiopaque iodinated contrast was injected into the TD under constant and gradual manual pressure. Results TD outflow was detected on the posterior surface of the junction between the internal jugular and the left subclavian veins, either as direct outflow (in 10 cases) or as an arc (in three cases). Reverse contrast progression was impossible in each of the attempts, probably due to valvular resistance and lumen obliteration, which completely prevented pressure infusion into the thoracic and abdominal parts of the TD. Conclusions We emphasize the impracticality of obtaining postmortem radiopaque images via retrograde contrast injection into the TD in formalinized or refrigerated bodies.