A depression in the calf on pressure indicates the presence of edema, which is commonly caused by cardiogenic and nephrogenic sources as well as by other diseases. Cardiogenic edema is usually seen in patients with heart failure, often in right heart failure. Edema of the lower extremities occurs because of stagnation of the circulation, with edema of the sagging area being the main cause, which can be clarified by cardiac ultrasound, electrocardiography and other examinations. Nephrotic edema usually starts from the face and eventually spreads all over the body, mostly caused by nephritis and renal failure, which can be clearly diagnosed through urine routine and renal function tests. In addition, patients with hypothyroidism can also have edema, usually with facial edema. Measurement of nail function can confirm the diagnosis.