① Lymphatic vessel anastomoses with vein: Contrast agent was found in vein in lymphatic obstruction area. It proves that there is lymphatic vein anastomosis. Lymphography usually cannot directly see the path.
② Lymphatic anastomosis: It is the most common collateral pathway, similar to collateral circulation after vascular occlusion. For example, when the lumbar lymph is completely blocked, the contrast agent is diverted to the opposite side through the communicating lymphatic vessels at the bifurcation of the aorta, showing the trunk of the opposite lumbar lymph. If the obstruction is located in groin or inferior iliac region, it can show a wide range of subcutaneous collateral lymphatic pathways in perineum, external genitalia and anterior abdominal wall of thigh.