PURPOSE To evaluate the predictability of the refractive correction achieved with a positional accommodating intraocular lenses (IOL) and to develop a potential optimization of it by minimizing the error associated with the keratometric estimation of the corneal power and by developing a predictive formula for the effective lens position (ELP). MATERIALS AND METHODS Clinical data from 25 eyes...

We present an analytical method to describe the accommodative changes in the human crystalline lens. The method is based on the geometry-invariant lens model, in which the gradient-index (GRIN) iso-indicial contours are coupled to the external shape. This feature ensures that any given number of iso-indicial contours does not change with accommodation, which preserves the optical integrity of t...

We examined the accommodative state of young adults wearing +2D and +3D reading spectacles under normal conditions and with the elimination of accommodative cues. Subjects' refractions were measured with an infrared PowerRefractor. Power of the vertical meridian was recorded for subjects viewing far and near targets in free space and through a Badal lens apparatus with and without reading spect...

purpose: to report three cases of alport syndrome in one  family with anterior lenticonus and retinal flecks. patients and findings: three members of one family with consanguineous parents are presented who had renal and ocular involvement. they had anterior lenticonus and a beaten bronze appearance in the macula. reduced visual acuity and photophobia were the chief complaints of these patients...

AIM Accommodation is the ability of the eye to change focus in order to maintain a sharp image of objects at various distances. The accommodative process is largely unknown in children and requires new assessment techniques. The aim of the study was to investigate this process in children with and without cerebral palsy (CP). METHOD In a descriptive case-control study, children with CP (n=15;...

We report a case of a 58-year-old man presenting with a spontaneous and late in-the-bag intraocular lens dislocation to the vitreous. A previous uneventful extracapsular cataract extraction with can-opener style capsulotomy and implantation of a polymethylmethacrylate three-piece lens was performed and, two years after the surgery, the patient developed capsule contraction syndrome with a fibro...

PURPOSE To identify whether static and dynamic aspects of accommodation other than accuracy are deficient in individuals with Down syndrome (DS) and whether poor accommodation is related to sensory or motor pathway deficits. METHODS Static aspects of accommodation (maximum accommodative response and lag) were measured with an autorefractor for both proximal and minus lens demands. Dynamic asp...

This article compares methods of axial length measurement for determining intraocular lens power and describes bimanual micro incision phacoemulsification for refractive lens exchange and routine cataract surgery, which offers an enormous advantage of maintaining a more stable intraocular environment during lens removal. This advantage may be especially important in high myopes who are at a gre...

PURPOSE The underlying causes of presbyopia, and the functional relationship between the ciliary muscle and lens during aging are unclear. In the current study, these relationships were studied in rhesus monkeys, whose accommodative apparatus and age-related loss of accommodation are similar to those in humans. METHODS Centripetal ciliary body and lens equator movements were measured during a...