Estimation of pupil size by digital photography.

Purpose: To evaluate a digital photography method of pupil size estimation over a broad range of illumination conditions and to compare this method with common clinical techniques.

Setting: College of Optometry, Ohio State University, Columbus, Ohio, USA.

Methods: Two examiners measured the pupil diameter in 45 right eyes at 3 illumination levels: <0.

Use of a run-in period to decrease loss to follow-up in the Contact Lens and Myopia Progression (CLAMP) study.

Rigid gas permeable (RGP) contact lenses are initially less comfortable to wear than spectacles. In previous studies evaluating the use of RGP contact lenses to control myopia, more subjects randomly assigned to wear RGP contact lenses have been lost to follow-up than spectacle wearers. Previous rigid contact lens myopia control studies have lost 44% and 47% of the rigid contact lens wearers.

Visual acuity results in school-aged children and adults: Lea Symbols chart versus Bailey-Lovie chart.

Purpose: To compare visual acuity results obtained using the Lea Symbols chart with visual acuity results obtained with the Bailey-Lovie chart in school-aged children and adults using a within-subjects comparison of monocular acuity results.

Methods: Subjects were 62 individuals between 4.5 and 60 years of age, recruited from patients seen in five optometry clinics.

The effect of eye closure on the post-lens tear film thickness during silicone hydrogel contact lens wear.

Purpose: The purpose of this study was to investigate the effect of eye closure on the thickness on the post-lens tear film (POLTF) during silicone hydrogel contact lens wear.

Methods: Ten subjects (mean age, 30.2 +/- 8.

Are we nearsighted when it comes to myopia treatment?

Purpose: The purpose of this article is to highlight the current research on myopia treatment and to speculate about the future of myopia treatment.

Methods: A review of the literature on myopia treatment in humans was performed using Medline, CRISP, and a variety of web pages. A summary of the research is presented in the article.

Clinical value of the Beery visual-motor integration supplemental tests of visual perception and motor coordination.

Purpose: Children may perform poorly on a test of visual-motor integration due to deficits in one or more of the following: visual analysis/visual spatial ability, motor coordination, visual conceptualization, or visual-motor integration. The VMI Supplemental Developmental Test of Visual Perception (VP) and VMI Supplemental Developmental Test of Motor Coordination (MC) were developed to help differentiate between such difficulties after administration of the Beery-Buktenica Developmental Test of Visual-Motor Integration (VMI). However, the clinical value of the VMI supplemental tests has not been reported.

Ocular component data in schoolchildren as a function of age and gender.

Purpose: To describe the refractive error and ocular components of a large group of school-aged children as a function of age and gender.

Methods: In this report, we describe the refractive error and ocular components of 2583 school-aged children (49.3% girls, overall mean [+/-SD] age 10.

Thickness of the pre- and post-contact lens tear film measured in vivo by interferometry.

Purpose: To evaluate an interferometric method for measuring the thickness of the pre- (PLTF) and postlens tear film (POLTF) in subjects wearing hydrogel contact lenses. The precision and accuracy of measuring postlens tear thickness is compared with a previous method based on optical pachymetry and mechanical measurement of contact lens thickness.

Methods: Reflectance spectra (562-1030 nm) from the front of an eye wearing a contact lens were measured at normal incidence.

Parental myopia, near work, school achievement, and children's refractive error.

Purpose: To quantify the degree of association between juvenile myopia and parental myopia, near work, and school achievement.

Methods: Refractive error, parental refractive status, current level of near activities (assumed working distance-weighted hours per week spent studying, reading for pleasure, watching television, playing video games or working on the computer), hours per week spent playing sports, and level of school achievement (scores on the Iowa Tests of Basic Skills [ITBS]) were assessed in 366 eighth grade children who participated in the Orinda Longitudinal Study of Myopia in 1991 to 1996.

Results: Children with myopia were more likely to have parents with myopia; to spend significantly more time studying, more time reading, and less time playing sports; and to score higher on the ITBS Reading and Total Language subtests than emmetropic children (chi(2) and Wilcoxon rank-sum tests; P < 0.

Ocular fixation during eye and head tracking with and without a visual cue to head position.

Purpose: This experiment had two purposes. The first purpose was to compare ocular fixation during eye tracking, head tracking, and head tracking with a visual cue to head position. The second purpose was to compare head tracking with and without a visual cue to head position.

Genetic loci for pathological myopia are not associated with juvenile myopia.

The purpose of this study was to evaluate chromosomal regions previously linked to pathological myopia for linkage to juvenile myopia in a sample of myopic children and their families. Of 125 families with a myopic child participating in the Orinda longitudinal study of myopia, 53 submitted 221 buccal swab samples for genetic analysis. Myopia in proband children was defined as -0.

Between-eye asymmetry in keratoconus.

Purpose: To report baseline differences between eyes on key variables in the Collaborative Longitudinal Evaluation of Keratoconus (CLEK) Study cohort compared with a retrospectively assembled group of myopic contact lens wearers without ocular disease.

Methods: A total of 1,079 keratoconus patients who had not undergone a penetrating keratoplasty in either eye before their baseline visit were enrolled and examined at baseline. Records from 330 contact lens-wearing myopes were reviewed.

Is visual memory predictive of below-average academic achievement in second through fourth graders?

Purpose: Controversy exists regarding the relation between visual memory and academic achievement.

Methods: A masked investigation of the relation between visual memory and academics was performed in 155 second-through fourth-grade children (mean age = 8.83 years).

The effect of accommodation on ocular shape.

Purpose: Ocular shape is altered in myopia, and accommodation during nearwork is a proposed risk factor for myopia. Using relative peripheral refractive error (RPRE), ocular shape was assessed before, during, and after a period of sustained nearwork to determine whether accommodation affects ocular shape.

Methods: Measurements of RPRE at 30 degrees in the nasal visual field were obtained using the spherical equivalent calculated from Canon R-1 autorefraction.

Performance and repeatability of the NEI-VFQ-25 in patients with dry eye.

Purpose: The use of the National Eye Institute Visual Function Questionnaire (NEI-VFQ) has increased as a method of assessing patients' impressions of their vision-specific quality of life. The purpose of this study was to assess the performance and test-retest repeatability of the 25-question format of the NEI-VFQ in patients with dry eye.

Methods: The self-administered NEI-VFQ-25 was administered to 75 patients with dry eye on two occasions in a university-based optometry practice.

The performance of the contact lens dry eye questionnaire as a screening survey for contact lens-related dry eye.

Purpose: The contact lens dry eye questionnaire (CLDEQ) is a self-administered survey developed to examine the distribution of dry eye symptoms among contact lens wearers. In this report, we examine the CLDEQ as a screening survey for contact lens-related dry eye and compare it with McMonnies' questionnaire.

Methods: The CLDEQ and McMonnies' questionnaire were administered to 367 unselected contact lens wearers at six clinics across the United States and Canada.

A pilot study. Depth perception and near stereoacuity: is it related to academic performance in young children?

Purpose: A study of the relationship between an overall measure of visual function at near, specifically stereoacuity, and academic performance in kindergarten through second grade was conducted.

Method: One hundred seventeen children (mean age = 7.33 +/-0.

Corneal staining in hydrogel lens wearers.

Purpose: The purpose of this study was to determine the factors that contribute to corneal staining in hydrogel lens wearers by examining the following variables: type of lens worn, wearing time and lens replacement schedule, lens care system, and topical and systemic medication use.

Methods: Five hundred full-time, successful hydrogel contact lens wearers were evaluated for corneal fluorescein staining at 20 clinical sites. Corneal staining was evaluated in five regions and was graded on a scale of 0 (no staining) to 4 (severe staining) in 0.

The effect of saccades and brief fusional stimuli on phoria adaptation.

Purpose: The purpose of this experiment was to determine whether brief fusional stimuli and saccades similar to those seen in the alternate cover test affect phoria disadaptation.

Methods: Three cover test conditions were performed randomly. Before each test condition, subjects fused for 2 min at an angle convergent to the subjective phoria.

Visual acuity in contact lens wearers.

Purpose: The difference between high- and low-contrast visual acuity provides a sensitive indicator of vision loss in ocular disease; however, the effect of refractive error correction on this difference is still debated.

Methods: High- and low-contrast visual acuity was measured in 116 rigid gas permeable contact lens wearers, 51 spectacle wearers, and 50 soft contact lens wearers with habitual and best correction. Twenty-nine of the soft contact lens wearers reported that they wore disposable contact lenses (discarded on a monthly or more frequent basis), whereas the other 21 soft contact lens wearers wore traditional soft contact lenses.