Chromatic dispersion based axial length estimation using retinal spectral domain optical coherence tomography

Area of Science:

• Ophthalmology
• Biomedical Optics
• Medical Imaging

Background:

• Accurate measurement of axial length is crucial for diagnosing and monitoring eye conditions.
• Spectral domain optical coherence tomography (SD-OCT) is a key imaging modality in ophthalmology.
• Chromatic dispersion in ocular tissues can affect imaging accuracy.

Purpose of the Study:

• To propose and validate a novel method for extracting human eye axial length from SD-OCT scans.
• To analyze the impact of chromatic dispersion on OCT measurements.
• To improve the accuracy of axial length measurements in vivo.

Main Methods:

• Developing a method to evaluate chromatic dispersion effects in the anterior segment and vitreous.
• Analyzing sub-spectral scans to quantify dispersion-induced axial shifts.
• Utilizing k-linearization and pixel-to-wavenumber calibration for accurate measurements.
• Validating the method with a model eye and in vivo retinal OCT scans.

Main Results:

• Demonstrated feasibility of the method using a model eye with adjustable parameters.
• Quantified axial shifts caused by chromatic dispersion in ocular media.
• Improved agreement with in vivo measurements by refining refractive index models for ocular tissues.

Conclusions:

• The proposed method enables accurate axial length extraction from SD-OCT scans by accounting for chromatic dispersion.
• Refining ocular tissue dispersion properties enhances the reliability of in vivo measurements.
• This technique holds potential for improved ophthalmic diagnostics and research.