If depressed edema of the ankle is present, it is necessary to distinguish whether the depressed edema is unilateral or bilateral in the ankle. If the edema is bilateral, whether the edema is severe in the morning or in the evening. If the edema is unilateral in the foot and ankle, you need to rule out unilateral inflammation, unilateral trauma, allergies, or certain mosquito bites to find the cause for more definitive treatment. Of course, unilateral limb edema needs to exclude unilateral limb thrombosis, which often has the presence of a primary disease. If the edema is bilateral and heavier in the afternoon, it is possible that the blood flow is not good bilaterally, the blood vessels have varicose or there is a part of the thrombosis, resulting in poor blood return to the edema. If the above conditions are excluded, bilateral edema of the ankles in the morning may be a systemic disease, most commonly renal disease and cardiovascular disease. Kidney disease is often associated with bilateral ankle edema and bilateral eyelid edema, and there may be increased foam in the urine that does not go away within a short period of time, while cardiac edema is often accompanied by arrhythmia or other symptoms of heart failure.