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. 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. For each experimental condition, tear volume was evaluated by measuring meniscus height and with the red phenol thread test. Fluorescein and non-invasive break-up time tests, as well as the observation of interference patterns and the estimation of the dry area extension, were employed to assess tear stability. Statistically significant differences were revealed in blink rate (F = 595.85, p < 0.001) and blink amplitude (χ(2) = 34.00, p < 0.001), with blink rate during fast- and slow-paced game play decreasing to almost 1/3 and 1/2 of baseline levels, respectively, and with a larger percentage of incomplete blinks during dynamic tasks. Fluorescein and non-invasive break-up time tests and dry area extension were able to differentiate between experimental conditions in general (F = 408.42, p < 0.001; F = 163.49, p < 0.001; χ(2) = 20.74, p < 0.001), as well as between fast- and slow-paced games, thus suggesting that tear quality was more affected than tear volume. Blink rate, blink amplitude, and tear film stability were compromised during the most dynamic visual display terminal task, suggesting a negative influence of not only the cognitive aspects of the task, but also of the rate at which new visual information is presented. Frequent breaks and blinking awareness training are recommended for visual display terminal users requiring prolonged periods of visually demanding dynamic computer play or work.

Purpose: To evaluate spontaneous eye blink rate (SEBR) and percentage of incomplete blinks in different hard-copy and visual display terminal (VDT) reading conditions, compared with baseline conditions. Methods: A sample of 50 participants (29 females, age range, 18–74 years) were recruited for this study. All participants had good ocular health and reported no symptoms of dry eye (OSDI score < 15). Face video recordings were captured while participants observed in silence a landscape picture at 2 m (baseline) and during six different, 6-minute controlled reading experimental conditions. Texts were presented in electronic (tablet and computer display at 100% and 330% zoom levels) and hard-copy (text in book position in silence and aloud and text pasted on the computer display) formats. Video analysis was subsequently conducted to assess blink parameters. Results: All reading conditions resulted in a decrease in SEBR when compared with baseline conditions (all P < 0.001), with the least negative impact corresponding to reading in a 330% expanded display. The percentage of incomplete blinks was found to increase when reading was conducted on an electronic platform, in contrast to hard-copy text. Conclusions: The high cognitive demands associated with a reading task led to a reduction in SEBR, irrespective of type of reading platform. However, only electronic reading resulted in an increase in the percentage of incomplete blinks, which may account for the symptoms experienced by VDT users. Spanish Abstract

Background: We objectively assessed the optical quality and intraocular scattering by means of parameters provided by a clinical double‐pass system in healthy young subjects and thereby we obtained new reference data for clinical diagnosis. We calculated normal values of neural contrast sensitivity function (nCSF) from the measured modulation transfer function (MTF) and the contrast sensitivity function (CSF). Methods: Eligible subjects were healthy adults aged from 18 to 30 years with a logMAR visual acuity (VA) of 0.0 or better and normal values of CSF. Optical quality measurements for a 4.0 mm pupil were performed using the Optical Quality Analysis System (OQAS) based on the double‐pass technique. The following parameters were analysed: the modulation transfer function cutoff frequency (MTF_cutoff), the Strehl^2D ratio, the OQAS values (OV) at 100, 20 and nine per cent contrasts and the objective scatter index (OSI). Results: A total of 178 volunteers responded to the call, of whom 181 eyes were finally part of the study taking into account the criteria for inclusion. The values for the optical quality parameters were: 44.54 ± 7.14 cpd (MTF_cutoff), 0.27 ± 0.06 (Strehl^2D ratio), 1.48 ± 0.24 (OV_100%), 1.58 ± 0.32 (OV_20%), 1.64 ± 0.39 (OV_9%), and 0.38 ± 0.19 (OSI). The nCSF calculated was 1.76 ± 0.21 (3 cpd), 2.13 ± 0.23 (6 cpd), 2.01 ± 0.28 (12 cpd) and 1.86 ± 0.33 (18 cpd). Conclusion: The normal values provided can be a useful tool for discriminating healthy eyes from early abnormal ones in which the optical quality or sensory function is impaired.

To describe the experience of parents caregiving children with visual impairment (VI), to determine how their quality of life (QoL) is assessed, and to summarize QoL indicators through a review of the literature. A thematic search through PubMed, PsycINFO, ProQuest and ERIC databases was performed of articles published in English in peer-reviewed journals between 1996 and 2016. Publications were included if they referred to both children or adolescents with VI and their parents, or the family context. The complete selection process disclosed 37 papers suitable for review. Researchers mainly used ad hoc interviews and questionnaires to investigate this topic. Two specific tools, the CarCGQoL (congenital glaucoma) and the OTI (congenital cataract), were identified. Most of the information collected referred to the parents' opinion concerning professional services, their needs and worries, the impact of VI on their emotional well-being and the strategies to assist parents to cope and adjust to the situation. The experience of caring for a child with VI is mainly influenced by psychosocial factors. Information and guidance to understand the child's visual condition are insufficient, and the available resources reinforce concerns of caregivers regarding the child's opportunities, expressed as negative emotional reactions.

Purpose: A prospective, randomized, double-masked, clinical trial was designed to evaluate distance and near contrast sensitivity (CS) in patients symmetrically, and randomly, implanted with 4 different multifocal intraocular lens (MIOL) designs (ReSTOR SN6AD1, ReSTOR SN60D3, ReZoom NXG, and Tecnis ZMA00) and a monofocal control group (Tecnis ZA9003), 6 months after cataract intervention. Methods: Photopic, mesopic, and mesopic with glare distance CS, as well as photopic near CS, was evaluated with the CSV-1000 CS test and the Vistech VCTS 6000 system, respectively, in a group of 180 patients attending the ophthalmology department of Sant Pau Hospital, Barcelona, for cataract intervention and lens implantation. Results: Statistically and clinically significant differences were found between the monofocal and multifocal lens groups at all spatial frequencies and illumination conditions, both during distance and near CS evaluation (all p<0.05), with the monofocal lens offering the best performance in all cases. Contrast sensitivity was similarly compromised in all MIOL models at distance, although MIOLs with diffractive optics and aspheric profiles showed a non–statistically significant trend to perform better in mesopic conditions. Near CS was lower for refractive, distance dominant lens designs, particularly at medium to high spatial frequencies. Conclusions: The present results, which reflect intraocular lens (IOL) characteristics in optics, profile, and add power, may contribute to help surgeons decide on the type of IOL most suitable for each patient by taking into consideration the individual needs for critical distance and near vision, both in terms of visual acuity and contrast sensitivity.

To use a double-pass system to compare the optical quality after photorefractive keratectomy (PRK) and laser in situ keratomileusis (LASIK) for mild to moderate myopia. Universitat Politècnica de Catalunya, Terrassa, Barcelona Institute of Ocular Microsurgery, Barcelona, Spain. Comparative case series. Optical quality was assessed with a clinical double-pass system preoperatively and 3 months after PRK or LASIK. The modulation transfer function (MTF), retinal image quality parameters (MTF cutoff frequency, Strehl ratio), and intraocular scattering (objective scatter index [OSI]) were calculated. This study evaluated 34 eyes that had PRK and 55 eyes that had LASIK. Both PRK and LASIK had a statistically significant impact on retinal image quality, although no significant differences between the techniques were observed. The MTF at 30 cycles per degree decreased by a factor of 1.50 in the PRK group and by a factor of 1.32 in the LASIK group. The MTF cutoff frequency decreased by a factor of 1.04 in the PRK group and by a factor of 1.06 in the LASIK group. The Strehl ratio decreased by a factor of 1.10 and 1.07, respectively. Photorefractive keratectomy and LASIK increased the objective scatter index by factors of 1.48 and 1.57, respectively. Significant correlations between the preoperative refraction and the OSI were found. Retinal image quality was similarly reduced with PRK and LASIK, with no significant differences between the 2 methods. Some PRK patients had a residual refractive error that might have been related to corneal-wound healing still present 3 months postoperatively.