May 2008
Volume 49, Issue 13
Free
ARVO Annual Meeting Abstract  |   May 2008
Accommodation Dynamics With Adaptive-Optics- Corrected Ocular Aberrations
Author Affiliations & Notes
  • E. Gambra
    Instituto de Optica, Consejo Superior de Investigaciones Cientificas, Madrid, Spain
  • L. Sawides
    Instituto de Optica, Consejo Superior de Investigaciones Cientificas, Madrid, Spain
  • S. Marcos
    Instituto de Optica, Consejo Superior de Investigaciones Cientificas, Madrid, Spain
  • Footnotes
    Commercial Relationships  E. Gambra, None; L. Sawides, None; S. Marcos, None.
  • Footnotes
    Support  CSIC-I3P2006 Predoctoral fellowship to EG; MEyC FPI fellowship to LS. MEyC FIS2005-04382 and EURYI Award to SM
Investigative Ophthalmology & Visual Science May 2008, Vol.49, 4562. doi:https://doi.org/
  • Views
  • Share
  • Tools
    • Alerts
      ×
      This feature is available to authenticated users only.
      Sign In or Create an Account ×
    • Get Citation

      E. Gambra, L. Sawides, S. Marcos; Accommodation Dynamics With Adaptive-Optics- Corrected Ocular Aberrations. Invest. Ophthalmol. Vis. Sci. 2008;49(13):4562. doi: https://doi.org/.

      Download citation file:


      © ARVO (1962-2015); The Authors (2016-present)

      ×
  • Supplements
Abstract

Purpose: : Ocular aberrations are thought to play a role in accommodation (i.e. larger lag in myopes associated to increased ocular aberrations or as cues to focus direction). We studied the role of ocular aberrations on accommodation dynamics (lag, fluctuations, aberration change and focus target tracking) by measuring optical aberrations dynamically, with and without adaptive-optics (AO) correction.

Methods: : Experiments were made with a fully-automatic custom AO system provided with a Hartman-Shack wavefront sensor, an electromagnetic deformable mirror (MIRAO, Imagine-Eyes), a motorized Badal system, a minidisplay for stimulus presentation and pupil imaging channel. Aberrations were measured dynamically (6.5 Hz) with natural and AO-corrected aberrations of the relaxed state. The pupil dynamics was recorded simultaneously. Four conditions were tested: (1) Increased accommodation demand (0-6 D) following a stair-case function (3 sec/step) (2) Off-On (4 D) accommodation stimulus (3 cycles, 3 sec/condition) (3) Increased accommodation demand (0-6 D) at 1.28 D/sec; (4) Decreased accommodation demand (6-0 D). Lag was defined as residual defocus (including spherical aberration). Fluctuations were estimated as the RMS standard deviationduring a 3 sec measurement. Five subjects were tested (age: 26.6±4,0; refractive error: -0.2±0,5 D; accommodative range > 6 D from IR dynamic retinoscopy).

Results: : 1) In 4 eyes, the accommodative lag increased significantly (p<0.0002) with AO correction (by 1.1±0.3 D on average). Lag decreased (by 0.2 D) with AO-correction in the more aberrated eye. 2) Fluctuations of accommodation peaked at intermediate demands both for natural (14.6±7.5% on average) and AO-correction (27.7±4.1% on average). AO-correction decreased the fluctuation range in all eyes and conditions (0.016±0.048 µm on average). 3) Spherical aberration decreased more consistently under AO correction than in the natural condition (by 0.031±0.030 µm and 0.015±0.025 µm, respectively on average, in the 0-6 D range). Coma showed systematic changes (both for natural and AO-corrected conditions) within a subject, but the trends varied across subjects. 4) All subjects followed the moving target without a significant delay and showed a slight accommodative inertia when the target stopped moving.

Conclusions: : Aberration dynamics are altered by correction of high order aberrations. Fluctuations of accommodation are reduced when aberrations are corrected. Our lag results indicate that while high amounts of aberrations may compromise accurate fixation, a small amount of aberrations may provide accommodative cues

Keywords: accomodation • aberrations 
×
×

This PDF is available to Subscribers Only

Sign in or purchase a subscription to access this content. ×

You must be signed into an individual account to use this feature.

×