Resumo/Summary:

Accommodation is the ability of the eye to actively change its dioptric power to focus objects at a wide range of distances. This is primarily achieved through a change in the shape and thickness of the crystalline lens varying its optical refractive power.

The ocular wavefront aberrations (WA) and, consequently, the retinal image quality, depend on the balance between the optical properties of the cornea and crystalline lens. Accommodation naturally changes this balance as it induces a change in lens geometrical and optical properties. Although accommodation compensates for retinal defocus, it also induces changes in ocular WA. Consequently, to understand the mechanisms of image quality control in the human eye, it is necessary to determine the factors that change ocular WA.

The purpose of this project is to study crystalline lens? optical and biometrics properties during accommodation. We intend to establish the relationship between its changes induced by accommodation through the analysis of the wavefront aberrations. We also aim to evaluate the impact of this changes in the subjective quality of the image formed in the retina using psychophysical tests.

An optical tomographer will be adapted to imaging the crystalline lens during accommodation. With an in-house built aberrometer we will measure, in vivo and in real time, the ocular optical properties changes during accommodation. Studying those properties changes of the crystalline during accommodation will allows us to better understand this process and apply this knowledge to the study of presbyopia, ametropia development and accommodative disorders. This will help in the diagnostic and treatment of these conditions and help to developed IOL that better mimes the crystalline lens.