Poor blood return is a condition in which there is an obstacle to the return of blood to the body and the blood does not circulate properly, mainly due to venous lesions. Clinically, the symptoms of poor blood return are closely related to specific lesions, the most common of which is poor blood return to the lower extremities, commonly seen in patients with lower extremity venous thrombosis, including phlebitis, saphenous varicose veins, lower extremity venous thrombosis, etc. The most prominent manifestation of the patient is obvious swelling of the limb, manifested as obvious swelling on one side of the limb, while sometimes appearing After a long time of swelling, the patient will experience numbness and pain in the limb. In case of saphenous varicose vein, there is also tortuosity of the vein, showing an abacus shape. In case of poor superior vena cava reflux, the patient may also experience swelling of the head and face, etc. Poor superior vena cava reflux is common in cases of malignant tumors with metastatic lymph nodes in the neck, such as lymphoma patients, etc.