Abstract
Purpose: :
To assess the mean changes of Optical Quality (OQ) and, Intraocular Scattering (IS) of the eye with ageing in healthy population. For patients older than 60 years old, to compare the same features between groups of non-operated eyes and those implanted with an IOL in cataract surgery.
Methods: :
We evaluated the retinal image quality in 568 eyes within a group of 298 healthy patients and stratified the sample in four groups of age (G1 18-30 yr, G2 31-45 yr, G3 46-60 yr, G4 61-91 yr). Patients included in the study did not report any ocular alteration. However, in group G4 subjects undergoing cataract surgery implanted with an IOL were also considered. Their best spectacle-corrected visual acuity (BSCVA) was 20/20 (20/36 for G4) or better assessed with a standard logMAR chart. Retinal images were acquired with a clinical double-pass (DP) instrument (OQAS, Visiometrics, Spain) using a 4-mm exit pupil diameter. From the DP images, several parameters related with the OQ of the eye (MTF, Strehl ratio (SR) and OQAS values (OV) at contrasts 100%, 20% and 9% and with the IS (Objective Scatter Index, OSI) were obtained.
Results: :
46.67% of patients included in the study were men. Mean age (yr ± SD) was: G1 22± 3, G2 38±3, G3 52±4 and G4 77±9. Mean logMAR BSCVA was: G1 -0.09±0.12, G2 -0.16±0.11, G3 -0.14±0.09 and G4 -0.03±0.11. OQ and IS parameters were for non-operated eyes (G1, G2, G3, G4): SR (0.24±0.07, 0.23±0.06, 0.20±0.05, 0.12±0.04), OV100% (1.33±0.31, 1.35±0.28, 1.28±0.24, 0.69±0.34) OV20% (1.37±0.41, 1.37±0.35, 1.24±0.36, 0.62±0.31) OV9% (1.39±0.49, 1.35±0.41, 1.16±0.36, 0.61±0.30) and OSI (0.50±0.51, 0.48±0.26, 0.61±0.27, 1.41±0.91) and SR 0.12±0.04; OV100% 0.65±0.3, OV20% 0.62±0.31, OV9% 0.61±0.26 and OSI 1.87±1.49 for eyes implanted with an IOL. Results showed a statistically significant increase of the IS (P<0.01) and decrease in OV parameters with age. Statistically significant differences were also found between non-operated eyes and those implanted with an IOL (G4) for the OSI parameter, meanwhile other OQ parameters remained similar.
Conclusions: :
We obtained values of OQ and IS in healthy population with a DP system in a clinical environment, and analyzed the corresponding changes with ageing. Results showed that IS is the parameter with a more marked change with age. However, all parameters of OV also had significant changes.
Keywords: imaging/image analysis: clinical • optical properties • contrast sensitivity