Monitoring Brain Perfusion and Cerebral Oximetry in Carotid Endarterectomy Surgeries

Patients scheduled to undergo a CEA procedure that have consented to participate in the study will be included in this observational study. Research Subjects: Indications for monitoring include patients scheduled for CEA that comply with the inclusion and exclusion criteria. Inclusion Criteria To be considered eligible to participate in this study, a patient must meet the inclusion criteria listed below: 1\. Consenting patients over 18 years, undergoing elective carotid endarterectomy at Barnes Jewish Hospital. Exclusion Criteria To be eligible for entry into the study, the patient must not meet any of the exclusion criteria listed below: 1. Emergency surgery 2. National Institute of health Stroke Scale (NIHSS) score \>=10 3. Sub-cutaneous hematoma at the ipsilateral intended area of the CerOx probe location. 4. Laceration or scalp injury at the ipsilateral intended area of the CerOx probe location which contraindicates placement of the adhesive on the skin. 5. Patient with implants located in the intended area of the CerOx probe location. 6. Prisoners 7. Non-consenting patient Or non-participating surgeon schedule of assessments and procedures 8. Pregnant or lactating women