99mTc-Dextran Lymphoscintigraphy SPECT/CT Unveils the Hidden Leakage Site in Recurrent Chylothoraxes

Chylothorax is defined as the accumulation of chyle in the pleural space, mainly by damaging to the thoracic duct. 99mTc-Dextran is a relatively new tracer for lymphoscintigraphy. A 40-year-old woman had recurrent chylothoraxes after thymoma resection and ligation of the thoracic duct owing to intraoperative suspected thoracic duct injury. She underwent lymphoscintigraphies using 99mTc-sulfur colloid and 99mTc-dextran, respectively, to identify the possible leakage site of the thoracic duct. The images showed increased 99mTc-dextran but unimpressive 99mTc-sulfur colloid activity at the leakage site. Based on the results, this patient received surgery anastomosing the thoracic duct and the azygos vein.