Ultrawide field, distortion-corrected ocular shape estimation with MHz optical coherence tomography (OCT)

Area of Science:

• Ophthalmology
• Biomedical Engineering
• Medical Imaging

Background:

• Ocular deformation is linked to biomechanical changes in the cornea and sclera.
• Conditions like keratoconus, congenital glaucoma, and pathological myopia involve structural alterations.
• Accurate ocular shape estimation is crucial for understanding these conditions.

Purpose of the Study:

• To propose and validate a novel method for estimating ocular shape.
• To quantify ocular curvature using localized Gaussian curvature.
• To assess the repeatability and applicability of the method in myopia.

Main Methods:

• Utilized ultra-wide field MHz swept-source optical coherence tomography (SS-OCT) with a Fourier Domain Mode-Locked (FDML) laser.
• Implemented distortion correction using ocular biometrics from an IOLMaster 700.
• Applied localized Gaussian curvature for quantifying ocular curvature over a wide field-of-view (65°×62°).

Main Results:

• Achieved repeatable ocular curvature shape measurements with an intraclass coefficient of 0.88 ± 0.06.
• Demonstrated the method's applicability in a pilot study involving 11 individuals with varying myopia.
• The technique successfully captured ocular curvature in a diverse group.

Conclusions:

• The proposed SS-OCT method with distortion correction provides repeatable ocular shape and curvature measurements.
• This technique is applicable for assessing ocular biomechanics in conditions like myopia.
• Further research can explore its diagnostic potential for various ocular pathologies.