purpose : to compare retinal nerve fiber layer (rnfl) profile in subjects with myopia and emmetropia using gdx variable corneal compensator (vcc) methods : besides ophthalmologic standard examination (refraction, visual acuity and slit-lamp examination, applanation tonometry, and funduscopy), perimetry and scanning laser polarimetry (slp) were performed. 171 healthy age-matched subjects with lo...

Purpose. To examine biomechanical parameters of the cornea in myopic eyes and their relationship with the degree of myopia in a western healthy population. Methods. Corneal hysteresis (CH), corneal resistance factor (CRF), Goldmann correlated intraocular pressure (IOP), and corneal compensated IOP (IOPcc) were measured using the ocular response analyzer (ORA) in 312 eyes of 177 Spanish subjects...

OBJECTIVE To assess the effect of depth of incision on the final outcome of radial keratotomy for correction of myopia. METHODS Sixty-five eyes with preoperative uncorrected myopia between 2.5-6.0D in subjects with a mean age of 29.2 (+/-7) years underwent radial keratotomy between Sept 1999-July 2002 in department of Ophthalmology, Military Hospital, Rawalpindi. Based on their preoperative d...

Purpose: We study the state of accommodative function in present-day schoolchildren using method computer accomodography. Patients and methods: 74 children (10–16 years old), 54 them with different degrees myopia 20 (control group) emmetropia were tested on accomodography devise Righton Speedy-K ver. MF-1. The strength response accorded to presented stimulus was determined by calculating coeffi...

Purpose: Recent studies have documented a link between axial myopia and ciliary muscle morphology; yet, the variation in biometric characteristics of the emmetropic ciliary muscle are not fully known. Ciliary muscle morphology, including symmetry, was investigated between both eyes of emmetropic participants and correlated to ocular biometric parameters. Methods: Anterior segment optical cohere...

PURPOSE To improve the description of the peripheral eye shape in myopia and emmetropia by using a new method for continuous measurement of the peripheral refractive state. METHODS A scanning photorefractor was designed to record refractive errors in the vertical pupil meridian across the horizontal visual field (up to +/-45 degrees ). The setup consists of a hot mirror that continuously proj...

Numerical experiments are performed on a first order exponential response function subjected to a diurnal square wave visual environment with variable duty cycle. The model is directly applicable to exponential drift of focal status. A two-state square wave is employed as the forcing function with high B for time H and low A for time L. Duty cycles of (1/3), (1/2) and (2/3) are calculated in de...

The purpose of the study was to evaluate the refractive results on a large cohort of patients who were implanted spherical or toric multifocal IOL's for cataract surgery or for refractive purpose. Preoperative refractive investigations included auto refractometer topography, pentacam, contact and noncontact biometry and many non-refractive investigations. The target in multifocal IOL usage was ...

A study was made of records of patients who have had at least 1 senile cataract removed and for whom refraction records were available. The risk of a cataract occurring was determined as a function of precataractous refraction. Emmetropia was found to provide a sharp borderline between the low risk (about 1:1000) of hypermetropes and an increasing risk (about 1:100) for moderate myopes for pati...