Volumetric imaging of trabecular meshwork dynamic motion using 600 kHz swept source optical coherence tomography

Area of Science:

• Ophthalmology
• Biomedical Engineering
• Medical Imaging

Background:

• Trabecular meshwork (TM) motion is crucial for aqueous humor drainage and maintaining intraocular pressure.
• Current phase-sensitive optical coherence tomography (OCT) methods assess TM motion using limited lateral scans, restricting throughput.
• Characterizing TM biomechanics is vital for evaluating aqueous outflow system function.

Purpose of the Study:

• To introduce the first volumetric imaging approach for assessing TM motion.
• To enhance examination throughput for TM biomechanical imaging.
• To provide a more comprehensive understanding of TM motion for diagnosing glaucoma and other outflow abnormalities.

Main Methods:

• Developed a novel volumetric OCT imaging approach for TM motion assessment.
• Implemented repeated volumetric scans to observe a continuous TM band.
• Utilized a customized volume registration algorithm for motion artifact correction and an automated segmentation algorithm for TM boundary identification based on OCT phase dynamics correlated with heartbeats.
• Expanded field of view by stitching multiple scans.

Main Results:

• Demonstrated the feasibility of volumetric TM motion imaging in a healthy subject.
• Revealed significant spatial variations in TM motion through stitched volumetric scans.
• Confirmed the ability of the developed algorithms to correct motion artifacts and accurately segment the TM.

Conclusions:

• The proposed volumetric imaging methodology significantly enhances examination throughput for TM biomechanical assessment.
• This approach offers unprecedented capabilities for scientific insight and diagnostic value in identifying aqueous outflow abnormalities.
• Volumetric TM motion imaging represents a significant advancement in understanding and diagnosing conditions affecting intraocular pressure.