Thoracic Duct, Cisterna Chyli, and Right Lymphatic Duct

The thoracic duct typically arises from the cisterna chili. It is subject to wide variation, from the abdominal region where it originates to the cervical region where it terminates. One of the most documented variations of the thoracic duct involves the location of the termination. The most frequent location of the termination is at the left internal jugular vein, followed by the junction of the left internal jugular and subclavian veins. When the thoracic duct reaches the thoracic area the diameter noticeably narrows; this marks the smallest external diameter, and gradually becomes wider as it ascends toward its termination. While the thoracic duct is typically 45 cm in length, more variation can be observed ranging from 36 to 45 cm. Unlike the thoracic duct, the right lymphatic duct is less distinguished in size and characteristics, usually 1-2 cm in length.