Diffuse stenosis is a description of the condition of blood vessels in clinical examinations. The main causes of this condition are atherosclerosis, arteritis, and thrombosis, which are related to the abnormalities of one’s own physical condition. 1. Arteriosclerosis: Prolonged high blood pressure, high blood lipids, and high blood sugar can easily cause arteriosclerosis, resulting in narrowing of the lumen. 2. Arteritis: generally related to infection and immune factors, prolonged inflammatory stimulation will lead to damage to the arterial lining, causing wall thickening, plaque formation, resulting in narrowing of the lumen. 3. Thrombosis: Abnormal coagulation function may cause multiple thrombosis, resulting in diffuse stenosis. Diffuse stenosis can easily cause abnormalities in the blood supply area, which requires timely medical observation and standardized treatment under the guidance of clinicians.