The clinical trial is for acute ischemic stroke patients measuring cerebral oxygen saturation (rSO2) values using pulse oximeter of near-infrared spectroscopy in the frontal lesion area and normal area of brain. The purpose of the clinical trial is to compare differences in cerebral oxygen saturation values, and the efficacy and safety are evaluated through additional exploratory clinical trials.

Inclusion Criteria:

• Adults over age 19
• Patients diagnosed with acute ischemic stroke within 7 days of symptom onset
• Patient's condition confirmed to have an acute ischemic stroke and also brain blood vessels condition confirmed through brain imaging such as Brain CT/CTA/CT perfusion and Brain MRI/MRA
• Patients voluntarily agree to participate and scheduled to participate in this clinical trial
• Patients willing to comply with the clinical trial protocol

Exclusion Criteria:

• Patients without brain imaging result
• Patients diagnosed with jaundice (hyperbilirubinemia) with abnormal skin color - Patients who find it difficult to wear medical devices for clinical trial on their foreheads
• Patients who has skull fractures of external shape not maintained normal
• Patients who does not agree to participate in this clinical trial
• Patients who are currently participating in another clinical trial or have participated in another clinical trial within 30 days of the screening date
• Patients who is determined from investigator that participating is inappropriate because it may affect the results of the clinical trial or ethically

Investigators must keep confidential all information related to the clinical trial protocol provided by the sponsor or clinical trial monitor. However, exceptions are made when disclosure is requested by the Institutional Review Board, research subjects, or health authorities pursuant to laws or related regulations.

Personal information of research subjects who participated in clinical trials will be used for up to 6 months after the end of clinical trials, and the collected information will be appropriately managed in accordance with the Personal Information Protection Act. This personal information is not provided to anyone other than the tester.