The ultrastructure of lens capsule abnormalities in Alport's syndrome is reported. An anterior lens capsule from a 29-year-old patient with lenticonus who was affected by Alport's syndrome was obtained at the time of surgery. The histopathologic findings showed the thickness of the anterior lens capsule was decreased and there were many vertical capsular dehiscences localized at the inner part ...

Lens dose is a concern during the treatment of facial lesions with anterior electron beams. Lead shielding is routinely employed to reduce lens dose and minimize late complications. The purpose of this work is twofold: 1) to measure dose pro-files under large-area lead shielding at the lens depth for clinical electron energies via film dosimetry; and 2) to assess the accuracy of the Pinnacle tr...

Chick eyes compensate for defocus imposed by spectacle lenses by making compensatory changes in eye length and choroidal thickness, a laboratory model of emmetropization. To investigate the roles of longitudinal chromatic aberration and of chromatic mechanisms in emmetropization, we examined the participation of different cone classes, and we compared the efficacy of lens compensation under mon...

PURPOSE Prior studies in humans measured time constants of biometric accommodative changes as a function of amplitude, and prior studies in monkeys used slit lamp videography to analyze dynamic lenticular accommodative movements. Neither of these studies related biometric changes to refractive changes. We wished to develop and test methodology to begin to test the hypothesis that ocular biometr...

PURPOSE To analyze ocular biometry parameters and evaluate their relationship with gestational age, birth weight, and postmenstrual age in prematurely born infants. METHODS The right eyes of 361 premature infants born before the 36th gestational week were evaluated. Birth weight, gestational week, and gender were recorded. An A-scan Biometer was used for obtaining axial measurements, includin...

PURPOSE To investigate the contribution of the individual ocular components, i.e. anterior chamber depth, lens thickness and vitreous chamber depth, to total axial length in patients with esotropic amblyopia. METHODS The study population consisted of 74 children, aged between 5 and 8 years: thirty-seven patients with esotropic amblyopia and 37 healthy volunteers (control group). The participa...

We present the possibility of using a triplet as an intraocular lens (IOL). The matrix method was used to calculate the power of this triplet for high myopia. The thickness of the lens, the distances between the edges of the IOL and the endothelium, the distances between the edges of the IOL and the iris, and the nfluence of axial displacement have been analyzed. We have also compared the size,...

We examine a mathematical model describing the behavior of the precontact lens tear film of a human eye. Our work examines the effect of contact lens thickness and lens permeability on the film dynamics. Also investigated are gravitational effects and the effects of different slip models at the fluid-lens interface. A mathematical model for the evolution of the tear film is derived using a lubr...

In this paper we present a variational formulation of the problem of determining the elastic stresses in a contact lens on an eye and the induced suction pressure distribution in the tear film between the eye and the lens. This complements the force-balance derivation that we used in earlier work [K. L. Maki and D. S. Ross, J. Bio. Sys., 22 (2014), pp. 235–248]. We investigate the existence of ...

Corneal thickness changes were monitored in ten subjects (1) over a 36-hour period without contact lens wear and (2) during 7 days continuous wear of three types of hydrogel contact lenses of different back vertex powers. Measured on awakening, the mean overnight central corneal edema without lenses was 3.0% ± 1.2%. With the lenses used in this study, the mean overnight corneal swelling over th...