Intraoperative Cerebral Hemodynamic Monitoring during Carotid Endarterectomy via Diffuse Correlation Spectroscopy and...

Area of Science:

• Neuroscience
• Medical Imaging
• Surgical Monitoring

Background:

• Carotid endarterectomy (CEA) carries risks of cerebral ischemia.
• Real-time monitoring of cerebral hemodynamics is crucial for patient safety during CEA.
• Current monitoring methods may have limitations in assessing cerebral blood flow and oxygenation.

Purpose of the Study:

• To evaluate the feasibility of noninvasive, real-time cerebral hemodynamic monitoring during CEA using DCS and NIRS.
• To assess changes in cerebral blood flow index (CBFi), cerebral autoregulation (CAR), and cerebrovascular resistance (CVR) during CEA.
• To investigate hemispheric compensatory responses and the impact of contralateral stenosis levels.

Main Methods:

• Diffuse Correlation Spectroscopy (DCS) for measuring cerebral blood flow index (CBFi).
• Near-infrared spectroscopy (NIRS) for assessing hemoglobin oxygenation changes.
• Estimation of CAR and CVR using CBFi and arterial blood pressure data.

Main Results:

• Carotid artery clamping significantly increased cerebrovascular resistance (CVR) and decreased ipsilateral CBFi.
• Partial recovery of CBFi, increased blood volume, and reduced CVR were observed post-clamping.
• Cerebral autoregulation (CAR) remained intact, with no significant differences in compensatory responses across contralateral stenosis levels.
• Lower ipsilateral CBFi levels were consistently observed during and after CEA compared to the contralateral hemisphere.

Conclusions:

• DCS, alone or with NIRS, is a valuable tool for real-time cerebral hemodynamic monitoring during CEA.
• This noninvasive technique allows for individualized strategies to optimize cerebral perfusion.
• Monitoring identifies critical hemodynamic changes, potentially improving patient outcomes during CEA.