BACKGROUND: Previous studies have demonstrated that enlarged perivascular spaces (EPVS) are a result of microvascular disease. To date, there are few reports about the relationship between EPVS and lacunar infarction. OBJECTIVE: To investigate whether EPVS is associated with lacunar infarction on the basis of cerebral magnetic resonance (MR) examination, clinical symptoms and signs, and past medical history of patients. DESIGN, TIME AND SETTING: Case contrast analysis was performed at the Department of Neurology, Shanghai Ninth People’s Hospital from January 2007 to January 2008. PARTICIPANTS: Sixty-eight patients with lacunar infarction were admitted to the Department of Neurology of Shanghai Ninth People’s Hospital, including 37 cases with first-ever infarction, and 31 with infarction recurrence. In addition, 53 healthy people were selected as controls. METHODS: All participants underwent past medical history investigation, nervous system examination, and cranial MR. The subjects were assessed using the JMW rating scale to identify the EPVS grade. MAIN OUTCOME MEASURES: EPVS scores of patients and controls; risk factors for cerebral vascular disease in patients with first-ever or recurrence of lacunar infarction. RESULTS: The EPVS grade from lacunar infarction patients was significantly higher than of the control group (P < 0.05). The EPVS grade in patients with recurring lacunar infarction was significantly higher than in patients with first-ever infarction (P < 0.05). In addition, hypertension incidence in patients with recurring lacunar infarction was significantly higher than in patients with first-ever infarction (P < 0.05). CONCLUSION: Results indicate that EPVS is related to the incidence of lacunar infarction. Earlier screening of EPVS, and the evaluation of EPVS severity, is of great importance to control the risk factors for cerebral vascular disease and to prevent lacunar infarction. BACKGROUND: Previous studies have demonstrated that enlarged perivascular spaces (EPVS) are a result of microvascular disease. of cerebral magnetic resonance (MR) examination, clinical symptoms and signs, and past medical history of patients. DESIGN, TIME AND SETTING: Case contrast analysis was performed at the Department of Neurology, Shanghai Ninth People’s Hospital from January 2007 to January 2008. PARTICIPANTS : Sixty-eight patients with lacunar infarction were admitted to the Department of Neurology of Shanghai Ninth People’s Hospital, including 37 cases with first-ever infarction, and 31 with infarction recurrence. participants underwent past medical history investigation, nervous system examination, and cranial MR. The subjects were assessed using the JMW rating scale to identify the EPVS grade. MAIN OUTCOME MEASURES: EPVS scores of patients and controls; risk factors for cerebral vascular disease in patients with first-ever or recurrence of lacunar infarction. RESULTS: The EPVS grade from lacunar infarction The patients were significantly higher than the control group (P <0.05). The EPVS grade in patients with recurring lacunar infarction was significantly higher than in patients with first-ever infarction (P <0.05). Results of the EPVS are related to the incidence of lacunar infarction. Earlier screening of EPVS, and the evaluation of EPVS severity, is of great importance to control the risk factors for cerebral vascular disease and to prevent lacunar infarction.