In Vivo Elasticity Mapping of Posterior Ocular Layers Using Acoustic Radiation Force Optical Coherence Elastography

Area of Science:

• Ophthalmology
• Biomedical Engineering
• Medical Imaging

Background:

• Retinal layer elasticity is crucial for understanding ocular biomechanics.
• Non-invasive methods for in vivo retinal elasticity mapping are needed.
• Current techniques lack the sensitivity to detect subtle changes associated with early disease.

Purpose of the Study:

• To develop and validate acoustic radiation force optical coherence elastography (ARF-OCE) for mapping retinal layer elasticity in vivo.
• To establish baseline elasticity profiles of healthy rabbit retinas.
• To investigate changes in retinal elasticity in a rabbit model of retinal disease.

Main Methods:

• ARF-OCE was employed to measure tissue deformation in response to acoustic radiation force.
• Proptosed healthy rabbit eyes were imaged to characterize normal retinal elasticity.
• A rabbit model of induced retinal inflammation was used to observe elasticity changes before and after disease onset.
• Histologic analysis was performed to correlate optical images with specific retinal layers.

Main Results:

• ARF-OCE successfully generated high-sensitivity elasticity maps of retinal layers.
• A consistent trend of increasing stiffness from the ganglion to the photoreceptor side was observed in healthy retinas (3-16 kPa).
• Significant alterations in retinal stiffness patterns were detected in the diseased rabbit model, indicating sensitivity to pathological changes.

Conclusions:

• ARF-OCE is a sensitive tool for differentiating retinal layers based on elasticity.
• The system can measure subtle mechanical property changes during disease onset, aiding early clinical diagnosis.
• This study validates ARF-OCE for in vivo retinal elasticity characterization and disease detection.