The purpose of this study is to evaluate the efficacy of Acetyl-L-carnitine in patient with Mild Cognitive Impairment associated with chronic cerebrovascular disease.

Inclusion Criteria:

• Age between 55 and 85 years old
• Patients with chronic cerebrovascular disease, who have modified Fazekas scale grade 2 ~ 3
• Patients wtih a diagnosis of MCI
• MOCA-K of 23 or less
• Patients who provided a signed written informed consent form

Exclusion Criteria:

• Patiens who are uneducated or illiterate
• Patiens previously treated with dementia
• Patients who received a nootropic agent or thyroid hormone within 4 weeks of visit 1
• Patients with cognitive impairment due to diseases other than cerebrovascular disease
• Patients with severe depression, schizophrenia, alcoholism, and drug dependence