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Identifier

000367386

Title

Ανάπτυξη βάσης δεδομένων φυσιολογικής ενδιάμεσης και κοντινής όρασης σε συνθήκες προσομοιωμένης πρεσβυωπίας

Alternative Title

Normative indermediate and near visual acuity in simulated presbyopia

Author

Τόντος, Χρήστος

Thesis advisor

Πλαϊνης, Σωτήριος

Reviewer

Τσιλιμπάρης, Μιλτιάδης
Παλλήκαρης, Ιωάννης

Abstract

ABSTRACT Purpose : To measure distance, intermediate and near visual acuity in simulated presbyopia when refraction is optimally corrected with spectacles for distance. The advantage of binocular over monocular viewing is also assessed. Methods: Participants were 34 healthy, young (average age: 27±5 years) emmetropes or myopes (average spherical equivalent: -2.29 ± 2.05 D), with no ocular abnormalities. Presbyopia was simulated with application of Cyclopentolate. Visual acuity was assessed monocularly (dominant eye) and binocularly, with an artificial pupil of 3.5 mm diameter, using the UoC logMAR charts (Plainis et al., 2007). Measurements were performed with optimal refractive correction for distance at :i) 4m / corrected distance visual acuity (CDVA), ii) 66cm / distance corrected intermediate visual acuity (DCIVA), iii) 33cm / distance corrected near visual acuity (DCNVA). The order of VA testing was counter-balanced. Results: Average (±SD) values were: CDVA -0.11±0.07 and -0.13±0.08 logMAR, DCIVA 0.06±0.09 and 0.01±0.07 logMAR and DCNVA 0.37±0.09 and 0.30±0.10 logMAR with monocular and binocular viewing, respectively. Visual acuity was better with binocular than monocular observation at all distances, with the binocular advantage increasing the higher the blur / the nearer the distance (from 0.02 logMAR at 4m, to 0.05 logMAR at 66cm and 0.07 logMAR at 33cm distance). An analysis of variance (ANOVA) on these data revealed a significant effect of viewing condition (p΄&λτ 0.001) and viewing/distance interaction (p=0.002). Conclusions: The study provides normative distance, intermediate and near visual acuity data in simulated presbyopia when refraction is optimally corrected for distance. Binocular vision improves visual acuity, especially for intermediate and near distances. It should be noted that age-related factors, e.g. neural degeneration, increased ocular scatter, may lead to reduced visual acuity values in real presbyopic eyes.

Language

Greek

Subject

Binocular

Cycloplegia

Ophthalmology

Διόφθαλμης συνάθροισης

Κυκλοπληγία

Φυσιολογικά δεδομένα

Issue date

2011-04-12

Collection