Ischemic foci in the left frontal lobe do not cause clinical symptoms, such as hemiparesis, hemiplegia, speech impediment, dizziness, headache and other symptoms do not appear. Small ischemic foci are formed when the small capillaries in the left frontal lobe are hardened and occluded, resulting in ischemia and necrosis of the local brain tissues, and the diameter of the ischemic foci is very small, which is not more than 3 mm. however, the presence of ischemic foci in the left frontal lobe suggests that there is atherosclerosis of the small capillaries in the brain. Therefore, patients should prevent the increase of ischemic foci, prevent the occurrence of cerebral infarction, start the secondary prevention of cerebrovascular disease, and actively regulate blood pressure, blood lipid and blood sugar to prevent cerebral atherosclerosis. At the same time, we should orally take aspirin or Polivir to prevent platelet aggregation. Normally, the diet should be low-salt, low-fat diet, especially to quit smoking, because smoking is more damaging to the endothelium of blood vessels.