| Abstract |
Purpose
One the most frequent oplthalmological operations that a big percentage of elderly people is subjected to, is cataract surgery. This pathological situation is characterized by reduction of the quality of vision, which results as a consequence of extensive opacities in the surface of crystalline lens. Consequently, the restoration/re-establishment of vision is achieved by the replacement of the crystalline lens by an intraocular lens. The aim of the present study was to estimate the effect of the artificial lens at the total chromatic aberration of the eye via the growth of a modified system of measurement called Badal optometer.
Methods
The participants of the present study were forty pseudophakic patients, thirteen of which was served as the control group. This group was used to validate measurement method and also to calculate the chromatic aberration of the eyes in vivo.
After the modified optometer was constructed, was selected the sample of measurement, with best spectacle corrected visual acuity at least 8/10. Moreover, a variety of chromatic filters were placed between the eye and the optometer in order to measure the chromatic focal shift for various wavelengths. Thus, we selected measurements for various types of intraocular lens and we created diagrams of chromatic difference of refraction in association with wavelength. By the comparison of these graphics with the diagram of chromatic aberration presented in the literature, we estimated the presence of the UV and blue-light absorbing that are added in the IOL material, at the total chromatic aberration of the eye.
Results
The average chromatic difference of refraction of the control group at a visible spectrum 490nm to 630nm, was calculated almost equal to 1D. Therefore, the chromatic aberration of the pseydophakic eye was improved in comparison to the crystalline lens.
As it is obvious in this study, eyes which has implanted with intraocular lens with UV absorber as well as those with filter for the blue spectrum, have increased chromatic aberration than that of an intact eye. Moreover lenses with blue-light absorber presented an additional increase concerning all the other lenses.
Conclusions
As a conclusion the type and the material of the artificial lens has a significant effect in its dispersive properties and as a consequence it affects its longitudinal chromatic aberration. Moreover, the total chromatic aberration of an eye which is implanted with IOL, suffer from increased LCA in comparison with an "intact" eye, without however we can confirm its negative impact in the quality of vision.
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