Improvement of Optics, Mechanics and the Usability of a Mechanical Eye Model for Vision Quality Evaluation of IOLs. ?

摘要

Cataract surgeries are one of the most frequent medical interventions with more than 11 million surgeries per year. During the surgery the clouded human lens is extracted and an artificial lens - the intraocular lens (IOL) - is implanted into the affected eye. Nowadays IOLs with different optical properties such as monofocal, bifocal or multifocal lenses are used for implantation. The postoperative lens position is influenced by healing processes resulting into shifts and tilts of the IOL that finally affect the refractive outcome. New IOL designs allow also the correction of high order aberrations and presbyopia. To fulfil the requirements of more sophisticated IOLs a closer investigation of the positioning sensitivity is necessary. A mechanical eye model was implemented for testing different types of IOLs under physiological conditions. New measurement setups are presented to get more detailed information about optical quality criteria such as the modulation transfer function (MTF), point spread function (PSF) and Strehl ratio. Additionally image quality is evaluated by the determination of the Zernike coefficients and the patients’ physiological impression of vision.