Abstract
Purpose :
Objective comparative measurement of PSF shape parameters between dilated and undilated subjects using double-pass aberrometry.
Methods :
Three-dimensional (3D) shape objective analysis of point spread function (PSF) and on modulation transfer function (MTF) on 66 healthy, unoperated, non-contact lens wearer eyes. Measurements were performed with double-pass aberrometry instrument (Optical Quality Analysis System II; Visiometrics, Terrassa, Spain). Metrics included the following: Strehl ratio, MTF Cutoff (c/degree), PSF width at 50% (half width at full maximum, reported in arcmin), PSF width at 10% (10% width at full maximum, reported in arcmin), and Objective Scatter Index (OSI), a proprietary Visiometrics metric. Measurements were performed under mesopic conditions, corrected for the Manifest Refraction Spherical Equivalent (MRSE).
Results :
Group A was formed of 34 dilated eyes (pupil diameter 6.5±1.3 mm; age 26.6±6.3 years; MRSE –1.54±2.41); group B was formed of 32 undilated eyes (pupil diameter 3.2±0.8 mm; age 25.9±5.7 years; MRSE –1.42±2.21). Eyes were dilated following a complete eye exam. Group A had average Strehl ratio 0.17±0.05, MTF cutoff 35.2±8.5 c/degree, PSF width at 50% 3.956±0.82 arcmin, PSF width at 10% 12.71±3.32 arcmin, and OSI 0.42±0.4. Eyes were undilated, prior to the eye exam that followed. Group B had average Strehl ratio 0.33±0.17, MTF cutoff 44.5±9.2 c/degree, PSF width at 50% 2.726±0.95 arcmin, PSF width at 10% 8.23±2.74 arcmin, and OSI 0.62±0.7. Age and refractive status were matched between the two groups; all PSF and MTF metrics had statistically significant differences (p < 0.05).
Conclusions :
This objective analysis of the two retinal image quality metrics of PSF and MTF in these young, healthy eyes provides a basis for comparison with pathology and age-affected ocular conditions. The study showed a statistically significant deterioration of all associated image quality metrics for the dilated eyes.
This is a 2020 ARVO Annual Meeting abstract.