Posters

Accommodative response to monochromatic stimuli with different spatial frequency content

Poster Details

First Author: A.Del Águila-Carrasco SPAIN

Co Author(s):    J. Esteve-Taboada   A. Moulakaki   A. Recchioni   R. Montes-Mico           

Abstract Details

Purpose:

To study if the accommodative response (AR) of healthy young subjects varies with the spatial frequencies content of monochromatic targets.

Setting:

University of Valencia, Spain

Methods:

The AR of 5 young healthy subjects was calculated from the Zernike defocus measured with a Shack-Hartmann wavefront sensor. Two different accommodative demands were considered for this experiment: 2 and 4 Diopters (D). Also, three targets were used in this study: one was a fragment of the Picasso’s Guernica, whereas the other two were low-pass filtered versions of the former. The different vergences were set using a Badal system and the targets were showed to the subjects using a monochromatic microdisplay.

Results:

AR from all the subjects was averaged. For the 2 D vergence, the mean AR was 1.09 ± 0.31, 1.00 ± 0.09 and 1.17 ± 0.11 D, for the normal image, the low-pass filtered image simulating a decimal visual acuity of 0.7 and for the low-pass filtered image simulating a decimal visual acuity of 0.5, respectively. In the 4 D vergence case, and for the same 3 images as before, the results were: 2.73 ± 0.27, 2.84 ± 0.14 and 3.04 ± 0.15 D.

Conclusions:

One-way analysis of variance for each vergence revealed that there were no statistically significant differences in the AR between the three different images (p greater than 0.05). Thus, monochromatic low-pass filtered images do not seem to affect the static accommodation of the eye. This may be of importance, given the fact that optical corrections, like phakic intraocular lenses or corneal refractive surgery, normally cause a decrease in the Modulation Transfer Function of the eye, and this decrease tends to be greater at higher spatial frequencies.

Financial Disclosure:

NONE