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Identifier

000383291

Title

Μελέτη της μονο-όρασης με τη χρήση οπτικών προκλητών δυναμικών

Alternative Title

Study of monovision using visual evoked potential

Author

Γάγγα, Μαρίας

Thesis advisor

Πλαϊνης, Σωτήρης

Reviewer

Murray, Ian
παλλήκαρης, Ιωάννης
Τσιλιμπάρης, Μιλτιάδης
Κιμιωνής, Γεώργιος

Abstract

PURPOSE: To study monovision performance using electrophysiological recordings of Visual Evoked Potentials (VEPs) at an intermediate distance (1 meter), and compare the results with those of Visual Acuity, exploring any possible differences in blurring the dominant vs. the non-dominant eye. Additionally, to explore how pupil diameter / retinal luminance influences monovision, under similar experimental conditions. METHODS: The effect of defocus, induced by positive lenses, was measured on the pattern reversal visual evoked potentials and on visual acuity (VA). All these measurements (VEPs and VA) were recorded binocularly, in monovision the defocus was alternating between the dominant and the non-dominant eye. We measured 12 young (29±6.84) volunteers under defocus up to 3.00 D in monovision conditions and up to 2.50D for binocular defocus. VEPs were elicited using reversing 10 arcmin checks with a contrast of 100% and mean luminance of 30 cd/m2. VA was measured under the same conditions using ETDRS charts. All these measurements were performed at 1 meter distance with best spherocylindrical correction. Finally, we followed exactly the same procedure, by applying artificial pupil of 3 and 6 mm in aperture (in 3 volunteers under cycloplegia). RESULTS: In conditions of monovision, amplitudes and implicit times of P100 component of VEPs were greater and shorter, respectively, in all cases than for binocular defocus. Statistical significant differences occur, between binocular and monocular defocus, from 1.50 D up to 3.00 D. However, no significant differences were observed between the two conditions of monovision (i.e. dominant eye vs. non-dominant eye selected for distance vision). Although VEP P100 latency and amplitude correlates well with VA for the range of defocus tested, VEPs for a more “sensitive” procedure in Abstract iv monovision correction. Artificial pupils result to better performance (shorter P100 latency and higher P100 amplitudes) for the 6 mm apertures than with 3 mm. CONCLUSIONS: Monovision performance at the distance of 1 meter was independent to the eye selected for distance (dominant vs. non-dominant). By comparing VEPs recordings with those of VA we showed that VEPs form a more sensitive technique to evaluate the effect of monovision on performance than VA. Monovision performance was better with larger pupil apertures, hinting that retinal illuminance is more important than depth-offocus (which is achieved with smaller pupils).

Language

Greek

Subject

Defocus

Monovision

Visual evoked potentials

Θόλωση

Μονο-όραση

Οπτικά

Οπτικά προκλητά δυναμικά

Issue date

2014-04-10