Edema of the ankles with a single press is a manifestation of significant lower extremity edema. Generally, this symptom has the following etiologies: first of all, chronic cardiac insufficiency. Because of the stagnation of blood in the circulation, venous return is impaired, and there is edema in the lower limb area and ankle, mostly depressed edema, that is, edema with a pit when pressed. In addition, the function of the lower limbs decreases, especially those who have varicose veins or venous valve hypoplasia, because standing for a long time will also lead to edema of the lower limbs, and the same edema will manifest as sunken edema. Some serious kidney diseases such as chronic nephritis nephrotic syndrome, etc., because of the presence of hypoproteinemia, will also appear lower limb edema.