Posters

Optical properties influence visual cortical resolution after cataract surgery and dissociate from perceived quality of vision

Poster Details

First Author: A.Martins PORTUGAL

Co Author(s):    A. Rosa   A. Miranda   M. Patricio   B. Harvey   M. Castelo-Branco   J. Murta     

Abstract Details

Purpose:

To investigate the relation between optical properties, population receptive fields (pRF), a measure of visual cortex resolution), visual function and subjective quality of vision, in patients recently submitted to cataract surgery.

Setting:

Ophthalmology Department, Centro Hospitalar e Universit�Ã�¡rio de Coimbra, Coimbra, Portugal

Methods:

The study includes 30 patients who recently received bilaterally diffractive bifocal intraocular lenses. We used functional magnetic resonance imaging and pRF modelling methods to assess pRF sizes across visual cortical regions (V1-V3). At the third week after second eye surgery, a complete ophthalmological and psychophysical examination was performed and subjects answered a quality of vision questionnaire.

Results:

Subjects with worse optical properties or with worse contrast sensitivity displayed larger pRF sizes (p=0.038). However, those who were more bothered by dysphotic symptoms presented lower pRF size fitting interception (p=0.012) and pRF size fitting slopes (p=0.020).

Conclusions:

Optical properties of the eye, in a recently modified optical visual system, influence pRF sizes. Our results show a dissociation between pRF sizes and perceived quality of vision, indicating that patients with better cortical resolution may have improved perception of dysphotic phenomena and therefore more dysphotopsia. PRF sizes are a valuable and non-invasive quantitative measure of the visual cortex resolution to assess quality of vision.

Financial Disclosure:

NONE