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Dynamics of ocular aberrations in keratoconus
Hema Radhakrishnan1, Amit Jinabhai, Clare O'Donnell
1Faculty of Life Sciences, Moffat Building, University of Manchester, Manchester, United Kingdom. hema.radhakrishnan@manchester.ac.uk
Clinical & Experimental Optometry
|June 19, 2010
Summary
Dynamic fluctuations in ocular aberrations are minimal in moderate keratoconus (KC) eyes during accommodation and after blinking. This suggests customized soft contact lenses for correcting higher-order aberrations in KC will be effective.
Area of Science:
- Ophthalmology
- Optometry
- Vision Science
Background:
- Keratoconus (KC) is a progressive eye condition characterized by thinning of the cornea.
- Understanding ocular aberrations in KC is crucial for effective vision correction.
- Monochromatic aberrations can impact visual quality in KC patients.
Purpose of the Study:
- To investigate dynamic changes in monochromatic ocular aberrations in moderate keratoconic eyes.
- To assess the impact of accommodation and tear-film changes on these aberrations.
- To evaluate the implications for vision correction strategies in keratoconus.
Main Methods:
- Measured ocular higher-order aberrations using a Hartmann-Shack aberrometer.
- Tested accommodative stimuli from 0 to 5.00 DS in 10 KC and 10 normal eyes.
- Recorded aberration changes for 15 seconds post-blink in 8 KC and 8 normal eyes.
Main Results:
- Spherical and coma-like aberrations showed no significant change with accommodation in KC eyes.
- Ocular higher-order RMS error tended to decrease post-blink in KC eyes, unlike normal eyes.
- Negative vertical coma reduced after blinking in KC eyes, decreasing overall higher-order error.
Conclusions:
- Dynamic fluctuations in ocular aberrations due to accommodation and tear film changes are minor in moderate KC.
- These findings suggest that correcting monochromatic higher-order aberrations in KC with custom soft contact lenses is feasible.
- The stability of aberrations implies successful application of advanced optical corrections for keratoconus.
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