Purchase this article with an account.
Ethan A. Rossi, Pinky Weiser, Janice Tarrant, Austin Roorda; Does correction of higher order aberrations improve visual performance in myopes?. Journal of Vision 2006;6(13):63. doi: https://doi.org/10.1167/6.13.63.
Download citation file:
© ARVO (1962-2015); The Authors (2016-present)
PURPOSE: Myopic observers may not benefit as much as emmetropes from adaptive optics (AO) correction in a visual acuity (VA) task. To investigate this, we measured AO-corrected VA in 10 low myopes and 9 emmetropes.
METHODS: Subjects were placed into either the myopic or emmetropic group based upon subjective refraction. Mean spherical error was –2.48 D (SD: 1.1) for the myopes, and –0.11 D (SD: 0.13) for the emmetropes. All subjects had a best-corrected VA of 20/20 or better, with a mean MAR for the myopes of 0.91′ (SD: 0.08′) and 0.77′ (SD: 0.08′) for the emmetropes. The AO scanning laser ophthalmoscope (AOSLO) was used to project ultra-sharp stimuli onto the retina of each observer. High contrast photopic acuity was measured using a tumbling E test.
RESULTS: The mean AO-corrected MAR was 0.62′ (SD: 0.03′) for the myopes and 0.51′ (SD: 0.07′) for the emmetropes. The difference is significant (p<0.0025). This effect is even greater (p<0.0014), when accounting for spectacle magnification and axial length, with myopes and emmetropes able to resolve critical features on the retina with a mean size of 2.99 microns (SD: 0.26) and 2.36 microns (SD: 0.35) respectively.
CONCLUSIONS: Myopes perform worse than emmetropes after AO-correction. This may be due to different retinal or neural limitations in the myope. Retinal stretching in the myopic eye may reduce cone density, imposing a lower sampling limit. Neural adaptation to the greater prevalent blur in myopes may render them cortically insensitive to the highest spatial frequencies in the smallest letters.
This PDF is available to Subscribers Only