Assessment of large-diameter and small-diameter SoftK specialty contact lenses for early-stage keratoconus.

Introduction: Soft contact lenses may be a good alternative for early-stage keratoconus (KC) patients who do not tolerate rigid gas permeable (RGP) lenses due to ocular discomfort or complications. This prospective study compared outcomes obtained after 2 weeks of wearing two types of soft silicone hydrogel contact lenses for keratoconus that varied in their diameter and central thickness (cc).

Methods: Patients with Amsler-Krumeich grades I or II KC were fitted with small-diameter (14.

Assessment of a Clinical Test for Detection of Alteration in Visual Perception Due to Astigmatism.

Purpose: Astigmatism blurs the retinal image of a circular spot along a particular orientation rendering it an elliptical shape. Astigmatic patients demonstrate adaptation to residual astigmatic blur that may affect their discrimination between oval and circular targets. The Wilkins Egg and Ball Test (WEBT) was created to detect altered visual perception due to residual astigmatic blur by discriminating a circle within a row of oval elements.

Central and peripheral corneal sagittal height in keratoconus and healthy eyes.

Purpose: To determine central and peripheral corneal sagittal height (z) values in keratoconus and healthy eyes with the Oculus Pentacam point-by-point data extraction software.

Methods: Forty eyes from patients with central or paracentral (4 mm) keratoconus (32.0 ± 12.

Impact of strabismus and binocular dysfunctions in the developmental eye movement test and test of visual perception skills: A multicentric and retrospective study.

Purpose: To compare the performance in the Developmental Eye Movement test (DEM) and the Test of Visual Perceptual Skills (TVPS) between three groups: individuals with strabismus and amblyopia, patients with binocular and accommodative dysfunctions, and subjects with normal binocular and accommodative function.

Methods: A multicentric, retrospective study including 110 children aged 6-14 years old was conducted to investigate the potential impact of strabismus, amblyopia, and different binocular conditions in DEM results (adjusted time in vertical and horizontal parts) and TVPS (percentiles in the seven sub-skills).

Results: No significant differences were found in the different subtests of the vertical and horizontal DEM and all the sub-skills in the TVPS between the three groups of the study.

Efficacy, predictability and safety of long-term orthokeratology: An 18-year follow-up study.

Purpose: To determine the efficacy, predictability and safety of long-term orthokeratology in children and adults.

Methods: Case histories of 300 orthokeratology patients (596 eyes; 34.3% children; 65.

Role of microfluctuations in accommodation: a novel approach to reduce non-accommodative noise.

Accommodative response and its possible role in myopia development has been explored through the study of the microfluctuations (MFs) of accommodation, which are commonly divided in high (1.0 to 2.3 Hz) and low (0.

Anterior chamber parameters in early and advanced keratoconus. A meridian by meridian analysis.

Purpose: To explore anterior segment changes with keratoconus onset and progression to determine whether structural changes are predominantly corneal, limbal or both. To investigate these changes in different corneal meridians.

Method: Eighty-four eyes with keratoconus and 49 healthy eyes were included in the study.

Comparative Analysis of Peripheral Corneal Geometry in Health and Keratoconus.

Objectives: To describe and compare corneal peripheral angles in normal and keratoconic eyes, to gain a better understanding of the topography of the periphery of the cornea in keratoconus and assist practitioners in the selection and fitting of large diameter contact lenses.

Methods: Eighty-eight eyes were included in the study, divided into three groups: healthy (A0, 28 eyes), keratoconus at stage I according to the Amsler-Krumeich classification (AI, 33 eyes) and keratoconus at stages II to IV (AII, 27 eyes). The Pentacam Scheimpflug system was used to manually measure the corneal peripheral angles corresponding to a chord length range between 8.

Real-Time Non-Intrusive Assessment of Viewing Distance during Computer Use.

Purpose: To develop and test the sensitivity of an ultrasound-based sensor to assess the viewing distance of visual display terminals operators in real-time conditions.

Methods: A modified ultrasound sensor was attached to a computer display to assess viewing distance in real time. Sensor functionality was tested on a sample of 20 healthy participants while they conducted four 10-minute randomly presented typical computer tasks (a match-three puzzle game, a video documentary, a task requiring participants to complete a series of sentences, and a predefined internet search).

The variability of corneal and anterior segment parameters in keratoconus.

Purpose: To analyse, describe and test diverse corneal and anterior segment parameters in normal and keratoconic eyes to better understand the geometry of the keratoconic cornea.

Method: 44 eyes from 44 keratoconic patients and 44 eyes from 44 healthy patients were included in the study. The Pentacam System was used for the analysis of the anterior segment parameters.

Blinking supervision in a working environment.

The health of the ocular surface requires blinks of the eye to be frequent in order to provide moisture and to renew the tear film. However, blinking frequency has been shown to decrease in certain conditions such as when subjects are conducting tasks with high cognitive and visual demands. These conditions are becoming more common as people work or spend their leisure time in front of video display terminals.

Effects of transient blur and VDT screen luminance changes on eyeblink rate.

Purpose: A study was designed to evaluate the efficacy of three different strategies aiming at increasing spontaneous eyeblink rate (SEBR) during computer use.

Methods: A total of 12 subjects (5 female) with a mean age of 28.7 years were instructed to read a text presented on a computer display terminal during 15min.

A new slit lamp-based technique for anterior chamber angle estimation.

Purpose: To design and test a new noninvasive method for anterior chamber angle (ACA) estimation based on the slit lamp that is accessible to all eye-care professionals.

Methods: A new technique (slit lamp anterior chamber estimation [SLACE]) that aims to overcome some of the limitations of the van Herick procedure was designed. The technique, which only requires a slit lamp, was applied to estimate the ACA of 50 participants (100 eyes) using two different slit lamp models, and results were compared with gonioscopy as the clinical standard.

Sources of variability of the van Herick technique for anterior angle estimation.

Background: The purpose of the present study was to investigate two potential sources of variability of the traditional van Herick technique for temporal anterior chamber angle estimation, namely the need to compare the depth of the peripheral anterior chamber (PACD) with the thickness of the peripheral cornea (PCT), and the possible loss of information resulting from restricting the assessment of the anterior chamber angle (ACA) to the temporal limbus.

Methods: Both image analysis and Scheimpflug photography were employed to measure PCT and PACD in a group of 82 eyes (mean ± SD age of 32.8 ± 4.

Blink rate, blink amplitude, and tear film integrity during dynamic visual display terminal tasks.

Purpose: The present study aimed at investigating the influence of the level of dynamism of two different visual display terminal tasks on spontaneous eyeblink rate, blink amplitude, and tear film integrity.

Material And Methods: A total of 25 healthy, young volunteers participated in the study. Blink rate and blink amplitude were recorded in silent primary gaze conditions and while subjects were playing two computer games of similar cognitive demands but different rate of visual information presentation.

Attitudes towards contact lenses: a comparative study of teenagers and their parents.

Purpose: This two-phase survey aimed to identify the beliefs and attitudes that create a barrier towards contact lens (CL) fitting among adolescents (aged 12-18 years) and their parents attending eye care practitioner clinics in Italy (phase 1) and Iberia (Spain and Portugal; phase 2). In phase 2, the sample was further focused, by limiting it to those adolescents who did not already wear CL.

Methods: The extent to which CL satisfy aesthetic, visual, and practical needs and their effectiveness, safety, and comfort in the general population and in adolescents was rated by respondents on a 5-point Likert scale.

Central thickness of hydrogel contact lenses as a predictor of success when fitting patients with tear deficiency.

A randomized, double masked, study was designed in order to investigate the relationship between the central thickness of hydrogel contact lenses and the overall comfort of patients with tear deficiency. To allow for statistical analysis, a thin lens was fitted in one eye and a thicker lens of the same characteristics in the contralateral eye. Subjects were asked to wear the lenses for 30 days on a normal daily wear basis and to graduate several factors such as comfort, dryness sensation, redness, photophobia, tearing, quality of vision and others.