Left-sided lacunar cerebral infarcts are relatively mild and most of them do not cause serious consequences. Left-sided lacunar cerebral infarction is caused by occlusion of the perforating arteries of the anterior and posterior circulation vessels on the left side, and the lesions are small in diameter and mostly involve the deep cerebral white matter area. 5. Some patients may have mild fine motor impairment and slurred speech. The above symptoms are mild and do not leave significant sequelae and do not affect the ability to take care of oneself. However, if recurrent lacunar cerebral infarction occurs, it may cause subcortical dementia and cognitive decompensation. Treatment of lacunar cerebral infarction on the left side is not difficult and the prognosis is optimistic.