Wavefront aberration and its relationship to the accommodative stimulus-response function in myopic subjects

Area of Science:

• Ophthalmology and Vision Science
• Optometry
• Biomedical Engineering

Background:

• Autorefractors are convenient for myopia research on accommodation.
• Ocular aberrations and pupil size can affect autorefractor measurements.
• Understanding these influences is crucial for accurate myopia research.

Purpose of the Study:

• To compare autorefractor accommodative accuracy with wavefront error measurements.
• To investigate the impact of accommodation demand, ocular aberrations, and pupil size on autorefractor readings.
• To determine how autorefractor measures relate to wavefront aberrations in myopic and emmetropic individuals.

Main Methods:

• Compared Shin-Nippon SRW 5000 autorefractor with Hartmann-Shack wavefront sensor.
• Measured accommodation stimulus-response curves (0-4 D) in 30 young adults (20 myopic, 10 emmetropic).
• Assessed wavefront aberrations at natural and 2.9-mm pupil sizes for varying accommodation levels.

Main Results:

• Spherical aberration increased with accommodation in all subjects.
• Autorefractor and wavefront sensor measurements agreed for emmetropes at a 2.9-mm pupil.
• For myopes, autorefractor error correlated with higher-order aberrations at natural pupil sizes.

Conclusions:

• Higher-order aberrations significantly influence the relationship between autorefractor and wavefront measurements.
• Agreement between methods depends on pupil size and refractive error.
• Hartmann-Shack sensor may underestimate accommodation error in myopes at higher accommodation levels compared to autorefractor.