Pupil dynamics on wavefront aberrations

  Damien Gatinel MD   Damien Gatinel, Rothschild Foundation, Paris, presented his research, “Impact of Pupil Dynamics on Wavefront Aberrations and Derived Metrics”, at a Clinical Research Symposium at the XXXV Congress of the ESCRS  in Lisbon. Dr Gatinel’s aberrometry research seeks to quantify the optical quality of the eye, predict the impact of aberrations on ocular refraction and retinal image quality and conceive efficient corrective solutions. To that end, he uses Zernike polynomials, which are the current standard for reporting the aberrations of the eye. However, the pupil is not a static entity. “Pupil constriction and centre/reference shift substantially modifies the wavefront aberrations qualitatively. Thus, the Zernike modes may not be well suited to accurately segregate between low- and high-order aberrations in the human eye,” said Dr Gatinel. This is in part because high-order Zernike modes contain low-order terms, leading to a great deal of confusion and difficulty in predicting refractive outcome in eyes with significant higher-order aberrations. “Instead, the D2V3 and the new G(n,m) polynomials may be an improvement over pre-existing wavefront analysis for addressing clinically relevant aberrations in more intelligible quantities,” he concluded. These investigations might help to solve the problem of patient dissatisfaction with night-time halos despite 20/20 vision and refractive emmetropia after keratorefractive surgery. These halos are caused by a narrow optical zone, leading to aberrations in its periphery.