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Identifier

000383318

Title

Μέτρηση και αξιολόγηση εκτροπών για μακρινή και κοντινή όραση μετά από ένθεση προσαρμοστικού φακού WIOL

Alternative Title

Measurement and evaluation of abertations for near and far vision after insertion of accommodative lens wiol

Author

Δημητρίου Αρχοντία

Thesis advisor

Παναγοπούλου, Σοφία

Reviewer

Παλλήκαρης, Ιωάννης
Κυμιωνής, Γεώργιος
Τσιλιμπάρης, Μιλτιάδης

Abstract

Τhe ability to focus on objects that are in the middle and short distance is lost with advancing age. One goal of refractive surgery is to correct presbyopia in order to eliminate the dependence on glasses for close work. Many attempts for therapeutic intervention including refractive surgery monoorasis, the insertion of accommodative and multifocal intraocular lenses etc., have been made so far. The purpose of this study is the measurement and evaluation of ocular aberrations during the process of accommodation - by moving a target from far to near distances. Our study involved six patients (5 women and 1 man) - 12 eyes - with a mean age of 67.3 years (standard deviation: ± 7,36 years) and the age ranged of 56-79 years. All patients had undergone cataract extraction surgery and the artificial IOL WIOL-CF® was implanted in both eyes. At the time that the study lasted, patients underwent postoperative examinations involving observation period from 3 to 5.5 years after surgery. After completion of the ophthalmologic testing, iTrace® ocular system was used, which is based on the ray tracing technique for measuring the aberrations of the eye. We recorded the wavefront and analyzed the ocular aberrations, of the patients, with the aid of Zernike polynomials. The measurements were made monocularly having its time the other eye covered, aligned with the optical axis and the line of sight as well. Initially, we analysed defocus and cylinder as recorded by iTrace® for observation at distant, intermediate and near distance. Due to small pupil diameter presented, we used the zone of 2mm for the analysis of our measurements. Then, the change in wavefront, when trying to focus at different distances, was observed with the use of three-dimensional refractive maps. In all cases the turn of refraction to myopia (myopic shift), when adjusting, was typical. Finally, by combining topography with wavefront map, we were able to conduct a more detailed study of the aberrations of each patient for the entire eye and the internal optics (the implanted intraocular lens). As revealed by the analysis of visual function maps, the values of astigmatism and coma (mainly vertical) are increased, giving the characteristic form to psf diagrams. Patients appear to be satisfied with the quality of vision offered by the WIOL-CF®. The majority of patients indicated that they can be served in daily life without the need for glasses. The results of our study, despite the small number of our sample, were encouraging demonstrating stability with the passage of time, giving way to future studies.

Language

Greek

Subject

Aberrations

Accommodative lens

Refraction

WIOL

Διάθλαση

Εκτροπές

Κύλινδρος

Προσαρμοστικός φακός

Σφαίρωμα