Analysis of Crystalline Lens Tilt and Decentration Using a Fully Automated Swept-Source Optical Coherence Tomography...

Area of Science:

• Ophthalmology
• Biomedical Engineering
• Optical Coherence Tomography

Background:

• Accurate measurement of ocular biometric parameters is crucial for refractive surgery and understanding ocular health.
• Crystalline lens decentration and tilt can influence visual outcomes and optical aberrations.
• Automated biometry aims to improve efficiency and reduce inter-observer variability.

Purpose of the Study:

• To assess the repeatability of the Eyestar 900 swept-source optical coherence tomography (SS-OCT) biometer.
• To measure crystalline lens decentration and tilt in healthy eyes.
• To investigate the correlation between lens position and other ocular biometric parameters.

Main Methods:

• Prospective study including 135 eyes of 135 patients.
• Triple measurements of ocular biometrics, including lens decentration and tilt, using the Eyestar 900 SS-OCT.
• Analysis of repeatability using within-subject standard deviation (Sw), coefficient of variability, and coefficient of repeatability.
• Exploration of correlations with keratometry (K1, K2), anterior chamber depth (ACD), lens thickness (LT), and axial length (AL).

Main Results:

• The SS-OCT biometer demonstrated high repeatability for lens decentration (Sw: 0.01-0.02 mm) and tilt (Sw: 0.39 mm).
• Axial length (AL) showed a significant correlation with crystalline lens tilt (r = -0.295, P < .001).
• Decentration in the Y-direction correlated with keratometry (K2) and anterior chamber depth (ACD) (P < .001, P = .007).

Conclusions:

• The Eyestar 900 SS-OCT biometer provides repeatable measurements for crystalline lens decentration and tilt.
• Axial length is the primary biometric parameter associated with crystalline lens tilt.
• Keratometry, ACD, and LT are associated with Y-direction crystalline lens decentration.