Calf vein thrombosis is medically known as lower extremity venous thrombosis, patients may experience lower extremity swelling, pain and other discomforts, it is recommended to consult a doctor in time. Lower extremity venous thrombosis is a disease in which the blood in the venous cavity of the lower extremity coagulates and forms a thrombus due to various reasons, blocking the venous cavity and leading to obstruction of venous return. The patient’s main manifestation is pain and swelling in the lower extremity, which may be accompanied by obvious pressure pain. With the progression of the lesion, the patient’s swelling can be gradually serious, the skin can be gradually purple, or even ulcers, if accompanied by superficial varicose veins, but also can be touched stripes, accompanied by tenderness, and some patients may also have a rise in body temperature and other systemic symptoms. If patients have the above symptoms and suspect venous thrombosis of the lower limbs, they should consult a doctor in time and improve the color Doppler ultrasonography, CT venography, D-dimer measurement and other tests under the guidance of the doctor, so as to clarify the diagnosis of the disease, and do not make blind judgment on your own, so as to avoid delaying the condition.