Imaging pulse wave propagation in human retinal vessels using full-field swept-source optical coherence tomography

Area of Science:

• Ophthalmology
• Biomedical Engineering
• Medical Imaging

Background:

• Assessing the biomechanical properties of the retinal vascular system is crucial for understanding ocular health and disease.
• Current methods for evaluating retinal vasculature may lack the necessary resolution or invasiveness for detailed biomechanical analysis.

Purpose of the Study:

• To introduce and validate a novel noninvasive technique for quantifying biomechanical properties of the retinal vascular system.
• To investigate retinal vascular dynamics with high temporal resolution using advanced optical coherence tomography.

Main Methods:

• Utilized phase-sensitive full-field swept-source optical coherence tomography (PhS-FF-SS-OCT) for high-resolution imaging.
• Measured minute tissue motion (approx. 10 nm accuracy) induced by vascular expansion.
• Analyzed arterial and venous pulse shapes, temporal delays, and frequency-dependent pulse propagation.

Main Results:

• Achieved unprecedented temporal resolution in assessing retinal vascular dynamics.
• Successfully determined pulse shapes, temporal delays, and capillary bed pulse propagation.
• For the first time, directly measured pulse waves exceeding 600 mm/s in retinal vessels of healthy subjects.

Conclusions:

• The developed PhS-FF-SS-OCT method provides a noninvasive approach to assess retinal biomechanics.
• This technique enables detailed characterization of pulse wave dynamics within the retinal vasculature.
• Offers potential for improved diagnosis and monitoring of vascular conditions affecting the eye.