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Football players’ contrast sensitivity comparison when wearing amber sport-tinted or clear contact lenses
Abstract
Background:
Many experiments are conducted each year in the sporting world to try and improve the existing technology and equipment in an effort to positively influence athletic outcomes. These studies, at times, are concerned about vision and how athletes can improve their visual inputs to respond most advantageously. Sports vision aids are becoming a more integral part of an athlete's equipment. Recently, sport-tinted contact lenses have become available to athletes of various sports. The purpose of this study was to compare football players' contrast sensitivity when wearing specially designed sport-tinted contact lenses to that when wearing clear contact lenses or no contact lenses in the case of an emmetropic athlete.
Methods:
Participants were fitted with either clear contact lenses or sport-tinted contact lenses. Spherical equivalent refractions were used because sport-tinted contact lenses are not currently available for astigmatic prescriptions. Contrast sensitivity was measured monocularly on a sine-wave grating chart of 4 spatial frequencies, each with decreasing contrast. Testing then was repeated with the other contact lens. Comparison was made to determine if statistically or clinically significant data would support the claim of increased contrast enhancement for the athletes while wearing the sport-tinted contact lenses.
Results:
Thirty-five subjects participated (35 left eyes), ranging in age from 18 to 32 years. All subjects were professional or collegiate football players. Testing done at 3, 6, 12, and 18 cycles per degree (cpd) of spatial frequency found statistically significant improvement with the sport-tinted contact lenses where P < 0.05. With an examination of the emmetropic-only subgroup, these same results were confirmed at 3 and 6 cpd. Although most of the results were statistically significant, it is questionable whether there is any clinically significant improvement in contrast enhancement while wearing these lenses.
Conclusion:
Sport-tinted contact lenses appear to have a statistically significant effect on contrast sensitivity when worn by a relatively low astigmatic or spherically refracted patient. These results also hold true for enhancing sensitivity in the emmetropic athlete. This information is dampened, however, when considering clinical significance. Overall, there does not appear to be overwhelming evidence that the sport-tinted lenses provide any clinically significant difference when considering contrast enhancement. There are always exceptions to any study; therefore, each case would have to be evaluated by the individual practitioner and the athlete.
... Previous studies suggested that glare and brightness on the surrounding of visual field can be reduced by enhancing visual comfort with wearing tinted lenses [5,8,12,13]. In addition, tinted lens will filter selective short wavelength and resulting in increment of contrast level. ...
... Amber tinted lens works as a substantial filter for a short wavelength colour (blue) that lead to decrement of chromatic aberration between the longer red wavelength and the transmitted mid range green. One of a recent study [8] showed a statistical significant difference of contrast sensitivity with amber lens worn compared with clear lens. However the result do not rise to the level of clinical significant changes, might be due to the test that was done indoors under standard room illumination whereas the amber lens was designed to cater outdoors surrounding under natural sunlight. ...
Contrast sensitivity function was believed can be enhanced by wearing amber tinted lenses. However the increment varied with respect to significant diagnosis. The aim of this study was to assess contrast sensitivity with and without wearing amber lens between youth hockey player and non-hockey player. Preliminary examination was done to assess on refractive status and ocular health among eighty healthy male subject aged between 13 to 16 years old where they were divided into youth hockey player (n=40) and non-hockey player (n=40). Pelli-Robson contrast chart was used in measurement of contrast sensitivity with latest refractive correction, two times; with and without wearing amber tinted lens. Contrast sensitivity between youth hockey player and non-hockey player seems to show a significant difference in both conditions of without and with wearing amber tinted lens with statistical value U = 312.0, z = −4.95, p
... 3,14-20 A recent study found that Maxsight lenses significantly improved CSF in collegiate and professional football athletes. 21 Another study confirmed that Maxsight CLs improve contrast discrimination and speed of visual recovery in bright sunlight when compared with clear lenses. 22 Maxsight lenses also provided better contrast discrimination when alternating between bright and shaded target conditions. ...
... This result confirms the Porisch findings in a study of athletes with the same amber CLs. 21 The Maxsight CLs were also significantly better than clear CLs combined with Eye Black going from 20/17 to 20/15. ...
Objectives:
Athletes who participate in outdoor activities seek products to reduce glare and improve contrast. This study compares performance of low-contrast visual acuity (VA) in bright outdoor conditions between the Maxsight Amber contact lens (CLs) and clear CLs with and without Eye Black grease.
Methods:
Seventeen subjects were fitted with clear CLs, clear lenses with Eye Black grease, Maxsight lenses with Eye Black grease, and Maxsight lenses alone. With each modality, the subject demonstrated low-contrast VA assessed and completed a questionnaire. At the end of testing, subjects completed a questionnaire to survey the performance of each modality.
Results:
The average low-contrast VA with clear CLs was 20/18.4, which improved to 20/17 with the addition of Eye Black grease (P=0.132). Significant improvement in low-contrast VA was seen with the Maxsight CLs to 20/15.4 (P<0.05), although it was not further improved with the addition of Eye Black grease. The results of the questionnaire showed a preference of the Maxsight CLs throughout the study for low-contrast VA.
Conclusions:
Although Eye Black grease has its place in sport and some sporting environments, the benefit in contrast acuity is insignificant. The better performance of the amber Maxsight lenses in this study demonstrates a visual performance benefit in bright sunlight.
... A recent study found that Nike Maxsight lenses significantly improved CSF in collegiate and professional football athletes. 23 The study cautioned that, while the improvements in contrast sensitivity were statistically significant, the results did not rise to the level of clinical significance. However, this study was performed indoors under "standard room illumination," whereas the Nike Maxsight lenses are designed for use in outdoor sports under natural sunlight. ...
... The resulting difference between testing in natural sunlight rather than under artificial lighting conditions magnified earlier effects that were not deemed clinically significant. 23 A number of sport situations contain subtle visual information with varying contrast conditions. For example, it is essential for a golfer to accurately identify subtle variations in the surface of the green. ...
The use of tinted and clear contact lenses (CLs) in all aspects of life is becoming a more popular occurrence, particularly in athletic activities. This study broadens previous research regarding performance-tinted CLs and their effects on measures of visual performance.
Thirty-three subjects (14 male, 19 female) were fitted with clear B&L Optima 38, 50% visible light transmission Amber and 36% visible light transmission Gray-Green Nike Maxsight CLs in an individualized randomized sequence. Subjects were dark-adapted with welding goggles before testing and in between subtests involving a Bailey-Lovie chart and the Haynes Distance Rock test. The sequence of testing was repeated for each lens modality.
The Amber and Gray-Green lenses enabled subjects to recover vision faster in bright sunlight compared with clear lenses. Also, subjects were able to achieve better visual recognition in bright sunlight when compared with clear lenses. Additionally, the lenses allowed the subjects to alternate fixation between a bright and shaded target at a more rapid rate in bright sunlight as compared with clear lenses. Subjects preferred both the Amber and Gray-Green lenses over clear lenses in the bright and shadowed target conditions.
The results of the current study show that Maxsight Amber and Gray-Green lenses provide better contrast discrimination in bright sunlight, better contrast discrimination when alternating between bright and shaded target conditions, better speed of visual recovery in bright sunlight, and better overall visual performance in bright and shaded target conditions compared with clear lenses.
... There is currently very little scientific information regarding these lenses. A very recent report on the visual performance of football players with AM-tinted contact lenses compared with clear contact lenses showed that, in a sample of 35 eyes from 35 football players, contrast sensitivity was significantly improved with the Amber Maxsight Ò tinted contact lenses, although whether this was clinically significant was questioned by the author (Porisch, 2007). No information was provided on the clear lenses used, which seemed to be quite varied and this could have affected the results obtained. ...
... The eyes examined in this study were all wellpigmented (grades 3–4 according to the grading system of Seddon et al. (1990), and therefore these results might not be the same if the sample included lesspigmented eyes. Despite significant differences from baseline being found for the GGM lenses, these straylight differences do not seem likely to affect the quality of vision when considering contrast enhancement at a clinical level (Porisch, 2007), although because they are conceived for sport activity the implications may be significant at that level. The variations with pigmentation and age among the population in larger studies could, however, reveal different results. ...
To investigate the effect of two tinted contact lenses (CL) designed for outdoor sports activity on the psychometric determination of retinal straylight using the compensation comparison method.
Thirteen emmetropic subjects were randomly fitted with two different tinted Nike Maxsight (Bausch & Lomb, Rochester, NY, USA) CL in one eye, while the contralateral eye was fitted with a clear lens made of the same material (Optima 38, Bausch & Lomb). Three valid straylight measurements were taken on each eye before and a few minutes after lens insertion, when lens stabilization had occurred.
The subjects' mean straylight values were 0.90 +/- 0.09 at baseline and 0.95 +/- 0.10 with the clear Optima 38 CL. Straylight values were 0.97 +/- 0.10 and 1.0 +/- 0.10 log units with the amber and grey-green tinted CL, respectively. Differences in straylight between baseline (without CL) and with the clear CL in place were neither statistically significant (p = 0.066) nor was there a significant difference between baseline and the amber CL (p = 0.052). However, the grey-green CL showed a statistically significant difference from baseline (p = 0.006). Differences in straylight with the clear CL compared with the grey-green CL were also statistically different from zero (p = 0.002) showing an increased straylight value for the tinted CL. These differences were variable, but consistent for each subject, thus those showing higher or lower changes with one tinted lens tended to show the same trend with the second lens (r(2) = 0.736).
Despite increases having been found in straylight values with tinted contact lenses, those changes are not likely to induce clinically significant changes in visual function under photopic conditions, even for the grey-green CL, which seems to increase straylight values more significantly than the amber CL. This difference between the tinted CL could suggest a wavelength dependence of straylight values, although this should be investigated further by controlling for pupil size and subjects' pigmentation, as well as by using neutral density filters.
... Another pressing question centers on the validity of the evidence supporting PVTI's claim that its lenses confer significant visual advantages to athletes. Many studies comparing the Nike MaxSight lenses to regular vision found a lack of significant evidence supporting their vision enhancement capabilities during sporting activities, [7][8][9] suggesting that any perceived improvement is placebo. PVTI primarily cites two studies from 2009 to 2011 funded by Nike and Bausch & Lomb, 10,11 which raises questions about potential bias. ...
This editorial examines a recent addition to the CL market: a tinted "performance" lens, used to enhance vision and reduce glare during sporting activity. We discuss the pros and cons and evidence supporting its use.
... These performance-enhancing claims are purported to be due to the manipulation of visible light transmitted to the eye based on the colour of the tint and the type of material used in the lens (2). These features supposedly improve visual factors such as visual acuity, depth perception, and contrast sensitivity, which enhances one's ability to discern crucial details, such as tracking the ball's trajectory and judging depth (2,16,17) which may assist with completing a successful catch. However, support for these purported benefits is lacking. ...
Introduction
Sunglasses are worn by outdoor athletes such as cricketers for many reasons, including comfort and glare reduction, which may help to improve vision. Anecdotally they are purported to have performance-enhancing benefits, but there is a lack of evidence for this. Further, it appears that fielders are the only position in cricket who wear sunglasses. Therefore, this study aimed to compare the catching performance of fielders when wearing three different colour sunglasses tints during an indoor, laboratory-based experiment.
Methods
Twenty-one male cricketers currently playing for a university or amateur provincial teams in Makhanda, South Africa, who were non-habitual sunglass wearers, were recruited for this study. An optometrist administered pre-screening tests. Players had four testing sessions during which they wore a different colour tint at each session indoors (clear, blue, G30 (rose), and red). Players were required to catch 18 balls projected from a bowling machine. The number of balls caught, as well as the quality of the catch, was recorded. At the final session, they were asked which tint they thought was best.
Results
Pre-screening tests showed that the red lens was best for contrast sensitivity and stereopsis. During data collection, sunglass tint did not affect catching performance. The players perceived the red lens as the worst and the G30 as the best.
Discussion
It can be concluded that catching performance indoors is not affected by tint colour.
... Lam (2002) also found a higher frequency of female vs. male CLMK cases (23) . It is well known that CL use provides a better appearance and imposes less restrictions on daily activities (24) . This may be the reason why our study showed a female predominance among CLMK cases. ...
ABSTRACT Purpose: The aim of this study was to analyze patient data and the laboratory results of corneal samples collected from patients followed at the Ophthalmology Department, Hospital São Paulo, Brazil over a 30-year period, and correlate the analize with contact lens wearing. Methods: Corneal samples from patients diagnosed clinically with microbial keratitis between January 1987 and December 2016 were included in this study. Cultures that were positive for bacteria, fungi, and Acanthamoeba spp. were analyzed retrospectively. To ascertain if the number of patients with contact-lens-associated microbial keratitis (as a risk factor for microbial infection) changed over time, the analysis was divided into three decades: 1987-1996, 1997-2006, and 2007-2016. Information pertaining to patient gender and age, as well as type of organism isolated, were compared among these periods. Results: The corneal samples of 10.562 patients with a clinical diagnosis of microbial keratitis were included in the study, among which 1.848 cases were related to the use of contact lenses. The results revealed that the frequency of contact-lens-associated microbial keratitis increased over the last two decades. Overall, females had contact-lens-associated microbial keratitis more frequently (59.5%). Patients aged 19-40 years also had contact-lens-associated microbial keratitis more frequently in all study periods. Staphylococcus spp. and Pseudomonas spp. were the most frequent Gram-positive and Gram-negative bacteria, respectively, in the microbial keratitis groups. Among the fungal cases of microbial keratitis, filamentous fungi were the most frequent fungi over the entire study period, with Fusarium spp. being the most frequent fungi in the group with microbial keratitis not associated with contact lens wearing (p
... Several human studies have investigated different visual attributes (visual acuity, contrast sensitivity, depth perception, low-contrast visual acuity, dynamic visual acuity, and hand-eye coordination) when wearing tinted lenses. These have revealed contradictory findings (Kuyk and Thomas, 1990;Wolffsohn et al., 2000;Pérez et al., 2003;Porisch, 2007;Kohmura et al., 2013), however, changes in color discrimination seems to be a common finding (Kuyk and Thomas, 1990;De Fez et al., 2002;Kohmura et al., 2013). ...
The amount and spectral composition of light changes considerably during the day, with dawn and dusk being the most crucial moments when light is within the mesopic range and short wavelength enriched. It was recently shown that animals use both cues to adjust their internal circadian clock, thereby their behavior and physiology, with the solar cycle. The role of blue light in circadian processes and neuronal responses is well established, however, an unanswered question remains: how do changes in the spectral composition of light (short wavelengths blocking) influence neuronal activity? In this study we addressed this question by performing electrophysiological recordings in image (dorsal lateral geniculate nucleus; dLGN) and non-image (the olivary pretectal nucleus; OPN, the suprachiasmatic nucleus; SCN) visual structures to determine neuronal responses to spectrally varied light stimuli. We found that removing short-wavelength from the polychromatic light (cut off at 525 nm) attenuates the most transient ON and sustained cells in the dLGN and OPN, respectively. Moreover, we compared the ability of different types of sustained OPN neurons (either changing or not their response profile to filtered polychromatic light) to irradiance coding, and show that both groups achieve it with equal efficacy. On the other hand, even very dim monochromatic UV light (360 nm; log 9.95 photons/cm²/s) evokes neuronal responses in the dLGN and SCN. To our knowledge, this is the first electrophysiological experiment supporting previous behavioral findings showing visual and circadian functions disruptions under short wavelength blocking environment. The current results confirm that neuronal activity in response to polychromatic light in retinorecipient structures is affected by removing short wavelengths, however, with type and structure – specific action. Moreover, they show that rats are sensitive to even very dim UV light.
... A successful visual rehabilitation using a rigid gas permeable (RGP) contact lens has been reported from Nepal in a nonophthalmic patient presenting with retinal dystrophy [12]. Contact lenses have improved the quality of life not only by correcting refractive errors but also by providing better appearance and less restriction in activities [13]. ...
Though, the use of contact lens and its availability is increasing with more world leading brands introduced, lack of strong laws and regulations against malpractice, patient’s un- awareness and hunting for cheaper products, lack of contact lens experts and their services are dragging the flourishment of healthy contact lens practice in developing countries like Nepal. To flourish contact lens practice is our paramount responsibility and that can be done by bridging the gap between the practitioner and the user. More epidemiological studies regarding contact lens use, practice, complications and compliance are needed to analyze the scenario of contact lens practice in Nepal.
... 7 Some of the previous studies found no difference in the CSF in subjects wearing spectacles and CL. 6 However, Ortiz et al. found lower CSF with cosmetic as well as iris tinted soft CL when compared to no correction. 8 Porish showed that the CSF can be improved in athletes with sport-tinted CL. 9 However, the improvement was too small to affect the performance of these athletes. ...
Purposes:
To compare contrast sensitivity function (CSF) with soft contact lens (SCL) and spectacles wear. To investigate the effect of a three-month period of SCL wear on CSF.
Methods:
Forty-seven myopic subjects with no history of contact lens (CL) wear were included in this longitudinal prospective study. CSF was measured with spectacles using the CSV-1000 (VectorVision, Greenvile, OH). Subsequently, subjects were fitted with a daily disposable lens (Nelfilcon-A, Stenofilcon-A or Nesofilcon-A) in one eye and a monthly disposable lens (Lotrafilcon-B, Comfilcon-A or Balafilcon-A) in the other eye and wore the same type of CLs for three months. CSF was measured again on the same day and after three months wearing CLs. Differences in CSF with spectacles and CLs on baseline and changes to CSF after three months of CLs wear were assessed. The effect of lens materials and wearing modality on CSF change was also investigated.
Results:
CSF was higher with CLs in comparison to the values with spectacles for spatial frequencies of 3, 6 and 12 cycles per degree (cpd) (p<0.05) while there was no difference for spatial frequency of 18 cpd (p=0.114). No significant difference was found in the CSF with CLs between baseline and after three months of lens wear (p>0.05). There was no difference in CSF between hydrogel and silicone CLs as well as when comparing daily with monthly wear CLs (p>0.05).
Conclusion:
CSF is better with CLs than with spectacles. CSF values with CL are similar between baseline and after 3 months of lens wear.
... Sportsmen commonly use tinted lenses to enhance visual performance including visual acuity and contrast sensitivity. 14,15 A popular brand of sunglasses comprising of the tints persimmon, black iridium and G30 is claimed to enhance depth perception. 16 ...
Background: Stereopsis is the accurate awareness of relative depth necessary for efficient hand–eye coordination and navigation. A popular brand of sunglasses claims to enhance depth perception.
Aim: This study set out to investigate the effect of tinted lenses on distance stereoacuity under varying retinal illumination.
Setting: This study was set at the Discipline of Optometry, University of KwaZulu-Natal.
Methods: A pretest–post-test research design was used. Forty participants were recruited using convenience sampling. The Howard–Dolman apparatus was used to measure distance stereoacuity with different tints of a popular sporting brand under varying retinal illumination. The tinted lenses and their respective transmission values used included persimmon (61%), light grey (38%), G30 (30%) and black iridium (10%). The placebo comprised of a white lens (100% transmission). Habitual distance stereoacuity was measured with no lens as the control. Retinal illumination was varied with neutral density filters to simulate mesopic and scotopic conditions. The Friedman and paired t-tests were used to analyse the data.
Results: The mean stereoacuity for each lens was significantly different across the three retinal illumination levels (p 0.05). A statistically significant difference (p = 0.012) was found with only the light grey tint under scotopic conditions when compared to the habitual stereoacuity. However, clinically significant differences were noted with the persimmon, light grey and black iridium tints. Overall, poorer stereoacuity was noted in mesopic and scotopic conditions compared to photopic for all five lenses.
Conclusion: Tinted lenses used had no statistically significant effect on distance stereoacuity but clinically significant changes were noted. However, the change in retinal illumination adversely affected distance stereoacuity.
... bursztynowy polecany jest w narciarstwie i sportach wodnych, a kolor zielonoszary zaleca się do gry w golfa. Nie ma badań naukowych, które wykazałyby zależność pomiędzy poprawą osiągnięć sportowych a noszeniem barwionych soczewek kontaktowych, jednakże takie rozwiązanie ma swoich zwolenników i każdy przypadek doboru takich soczewek powinien być rozpatrywany indywidualnie [23][24][25][26][27]. ...
... Qualquer desportista deve possuir uma acuidade visual próxima de 10/10, ou então corrigida por óculos ou lentes de contacto que quando necessário melhoram a sua performance (Porish, 2007). Deste modo, o futebol pressupõe uma visão estereoscópica indispensável às informações topográficas necessárias para a actualização das condutas motoras face às tarefas que se apresentam. ...
Policies are open in order to promote integration of adapted sport into general sport. The project Blanquerna Inclusion would bring knowledge and strategies to facilitate the process of social inclusion in the sports system. The project will involve athletes, technicians and managers, representing single sport federations and federations of sports for people with disabilities. As a first step, from a sociocognitive perspective, beliefs and attitude are evaluated into a group of participants, in all three roles, representing the federations of sports for people with disabilities. A technique based on Fishbein and Ajzen model and a content analysis strategy, using triangulation of expert judges, will be used. We describe differences in attitudes between men and women, over their conception of adapted sports and athletes with disabilities, and differences in beliefs about social inclusion, among the group of athletes and the group of coaches and managers.
... Qualquer desportista deve possuir uma acuidade visual próxima de 10/10, ou então corrigida por óculos ou lentes de contacto que quando necessário melhoram a sua performance (Porish, 2007). Deste modo, o futebol pressupõe uma visão estereoscópica indispensável às informações topográficas necessárias para a actualização das condutas motoras face às tarefas que se apresentam. ...
Through this study, we intend to evaluate whether the chromatic variation in the equipment of the goalkeeper (GK) have interference on the accuracy of soccer players when they shoot at goal. Our goal is to determine the degree to which players can isolate visual stimuli related to the distraction as a function of the polychrome outfit of the GK to make a shot on goal. In this sense, we analyzed 40 players in the Portuguese national football league, the trajectory of the ball cap on goal during a training situation, studying the precision will change color depending on the GK. We used four different tests to quantify the results, by which combine static and dynamic situations of the attackers, along with a neutral colored dress and an alive color of the GK clothes. The results show differences in the various tests.
... On a sunny day, a lens with low luminous transmittance is assumed to be usable without an effect on lowcontrast visual acuity. Recently, although the usage and situations were very different from the lenses used in this study, there have also been reports regarding the effect of colored contact lenses in sports activities (Porisch, 2007;Cerviño et al., 2008). Erickson et al. (2009) studied and reported the effect of colored contact lenses; they found that using amber and gray-green contact lenses with luminous transmittances of 50% and 36%, respectively, could achieve better contrast sensitivity than using colorless lenses in bright sunlight. ...
The purpose of this study was to clarify the effect of colored lenses on visual attributes related to sports activities. The subjects were 24 students (11 females, 13 males; average age 21.0 ±1.2 years) attending a sports university. Lenses of 5 colors were used: colorless, light yellow, dark yellow, light gray, and dark gray. For each lens, measurements were performed in a fixed order: contrast sensitivity, dynamic visual acuity, depth perception, hand-eye coordination and visual acuity and low-contrast visual acuity. The conditions for the measurements of visual acuity and low-contrast visual acuity were in the order of Evening, Evening+Glare, Day, and Day+Glare. There were no significant differences among lenses in dynamic visual acuity and depth perception. For hand-eye coordination, time was significantly shorter with colorless than dark gray lenses. Contrast sensitivity was significantly higher with colorless, light yellow, and light gray lenses than with dark yellow and dark gray lenses. The low-contrast visual acuity test in the Day+Glare condition showed no significant difference among the lenses. In the Evening condition, low-contrast visual acuity was significantly higher with colorless and light yellow lenses than with dark gray lenses, and in the Evening+Glare condition, low-contrast visual acuity was significantly higher with colorless lenses than with the other colors except light yellow. Under early evening conditions and during sports activities, light yellow lenses do not appear to have an adverse effect on visual attributes.
... There is a large body of literature suggesting that tinted contact lenses can improve a range of visual abilities including better contrast discrimination in bright sunlight and reduced photostress recovery times (36)(37)(38). Similarly, tinted intraocular lenses (eg, Acrysof natural; Alcon) have been shown to reduce photostress recovery times, reduce glare disability, and improve contrast discrimination (39,40). ...
Macular pigment (MP) is composed of the yellow, blue-absorbing carotenoids lutein and zeaxanthin. Although distributed throughout the visual system, MP is heavily concentrated in the central retinal area (eg, screening the foveal cones). Because light must pass through MP before reaching the receptors, it filters significant amounts of short-wave energy. Individual variation in peak absorbance is large and ranges from 0.0 to 1.6 optical density units depending largely on dietary intake. Several important functions of MP have been proposed. MP may serve to protect the retina from damage by absorbing actinic short-wave light (analogous to internal sunglasses) or by inactivating highly reactive free radicals and oxygen triplicates that are the by-product of light-driven cellular activity. MP may also serve, as proposed more than a century ago, to improve the retinal image through optical mechanisms. Recent data suggest that the MP carotenoids reduce glare discomfort and disability, shorten photostress recovery times, enhance chromatic contrast, and increase visual range (how far one can see in the distance). Lutein and zeaxanthin within the brain might also increase temporal processing speeds. This article reviews the influences of MP on visual function by exploring the implications of these visual improvements for baseball players.
Several lifestyle choices made by contact lens wearers can have adverse consequences on ocular health. These include being non-adherent to contact lens care, sleeping in lenses, ill-advised purchasing options, not seeing an eyecare professional for regular aftercare visits, wearing lenses when feeling unwell, wearing lenses too soon after various forms of ophthalmic surgery, and wearing lenses when engaged in risky behaviours (e.g., using tobacco, alcohol or recreational drugs). Those with a pre-existing compromised ocular surface may find that contact lens wear exacerbates ocular disease morbidity. Conversely, contact lenses may have various therapeutic benefits. The coronavirus disease-2019 (COVID-19) pandemic has impinged upon the lifestyle of contact lens wearers, introducing challenges such as mask-associated dry eye, contact lens discomfort with increased use of digital devices, inadvertent exposure to hand sanitizers, and reduced use of lenses. Wearing contact lenses in challenging environments, such as in the presence of dust and noxious chemicals, or where there is the possibility of ocular trauma (e.g., sport or working with tools) can be problematic, although in some instances lenses can be protective. Contact lenses can be worn for sport, theatre, at high altitude, driving at night, in the military and in space, and special considerations are required when prescribing in such situations to ensure successful outcomes. A systematic review and meta-analysis, incorporated within the review, identified that the influence of lifestyle factors on soft contact lens dropout remains poorly understood, and is an area in need of further research. Overall, this report investigated lifestyle-related choices made by clinicians and contact lens wearers and discovered that when appropriate lifestyle choices are made, contact lens wear can enhance the quality of life of wearers.
Purpose: Anecdotal evidence suggests that some sunglass users prefer yellow tints for outdoor activities such as driving, and research has suggested that such tints improve the apparent contrast and brightness of real-world objects. The aim of this study was to establish whether yellow filters resulted in objective improvements in performance for visual tasks relevant to driving.Methods: Response times of nine young (age 31.4 ± 6.7 years) and nine older (age 74.6 ± 4.8) adults were measured using (a) video presentations of traffic hazards (driving hazard perception task), and (b) a simple low-contrast grating which appeared at random peripheral locations on a computer screen. Response times were compared when participants wore a yellow filter (with and without a linear polariser) versus a neutral density filter (with and without a linear polariser). All lens combinations were matched to have similar luminance transmittances (approximately 27%). Results: In the driving hazard perception task, the young but not the older participants responded significantly more rapidly to hazards when wearing a yellow filter than with a luminance matched neutral density filter (mean difference 450 ms). In the low-contrast grating task, younger participants also responded more quickly for the yellow filter condition but only when combined with a polariser. Although response times increased with increasing stimulus eccentricity for the low-contrast grating task, for the younger participants this slowing of response times with increased eccentricity was reduced in the presence of a yellow filter, indicating that perception of more peripheral objects may be improved by this filter combination. Conclusions: Yellow filters improve response times for younger adults for visual tasks relevant to driving.
Contact lens-related problems are common and can result in severe sight-threatening complications or contact lens drop out if not addressed properly. We systematically reviewed the most important and the most common contact lens-related complications and their diagnosis, epidemiology, and management according to the literature published in the last 20 years. Alipour Fateme 1 Eye Research Center, Farabi Eye Hospital, Tehran University of Medical Sciences, Tehran Khaheshi Saeed 2 Eye Research Center, Farabi Eye Hospital, Tehran University of Medical Sciences, Tehran Soleimanzadeh Mahya 3 Eye Research Center, Farabi Eye Hospital, Tehran University of Medical Sciences, Tehran Heidarzadeh Somayeh 4 Eye Research Center, Farabi Eye Hospital, Tehran University of Medical Sciences, Tehran Heydarzadeh Sepideh 5 Eye Research Center, Farabi Eye Hospital, Tehran University of Medical Sciences, Tehran Fonn D. Targeting contact lens induced dryness and discomfort: What properties will make lenses more comfortable. © 2017 Journal of Ophthalmic and Vision Research Published by Wolters Kluwer - Medknow.
To compare the chromatic contrast sensitivity function (CSF) for the blue-yellow opponent channel (BYOC) between female badminton players and non-athlete controls.
We recruited 40 young females (18-25 years old) who played badminton for at least 5 consecutive years as the test group, and 30 age-matched female controls who had no history of regular physical activity. The Pattern Generator™ system was used to test the CSF for the BYOC which was performed at three spatial frequencies (SFs) of 2 cycles per degree (cpd), 5 cpd, and 25 cpd.
Comparison of BYOC thresholds showed significantly better results in the test group for all three SFs (P<0.001). Band pass shift (better CSF in the middle SF) was seen in the test group. The control group had low pass (better CSF in the low SF). Ocular motility (heterophoria, fusional convergence and divergence at far and near distances, and near point of convergence) was better in the test group, but the inter-group difference was not significant.
The BYOC threshold results for badminton players indicated a better visual performance which may be a result of enhanced performance of the parallel processing of the parvocellular and magnocellular systems. This may be inherent and/or acquired in badminton players. In addition, badminton players appear to have developed sensory-motor programmed activities. Testing the CSF for BYOC may be useful for athlete selection in different levels and/or used as a criterion for screening players in the field of badminton.
Anecdotal evidence suggests that some sunglass users prefer yellow tints for outdoor activities, such as driving, and research has suggested that such tints improve the apparent contrast and brightness of real-world objects. The aim of this study was to establish whether yellow filters resulted in objective improvements in performance for visual tasks relevant to driving.
Response times of nine young (age [mean ± SD], 31.4 ± 6.7 years) and nine older (age, [mean ± SD], 74.6 ± 4.8) adults were measured using video presentations of traffic hazards (driving hazard perception task) and a simple low-contrast grating appeared at random peripheral locations on a computer screen. Response times were compared when participants wore a yellow filter (with and without a linear polarizer) versus a neutral density filter (with and without a linear polarizer). All lens combinations were matched to have similar luminance transmittances (~27%).
In the driving hazard perception task, the young but not the older participants responded significantly more rapidly to hazards when wearing a yellow filter than with a luminance-matched neutral density filter (mean difference, 450 milliseconds). In the low-contrast grating task, younger participants also responded more quickly for the yellow filter condition but only when combined with a polarizer. Although response times increased with increasing stimulus eccentricity for the low-contrast grating task, for the younger participants, this slowing of response times with increased eccentricity was reduced in the presence of a yellow filter, indicating that perception of more peripheral objects may be improved by this filter combination.
Yellow filters improve response times for younger adults for visual tasks relevant to driving.
Unlabelled:
: The building blocks of effective sports vision are visual acuity and contrast sensitivity. Proper measurement of these spatial vision attributes is necessary for repeatability in the clinic or in the laboratory. The most repeatable method of testing visual acuity is with logMAR charts-either the Bailey-Lovie chart or the Early Treatment Diabetic Retinopathy Study chart. The Pelli-Robson and the Mars are the most repeatable contrast sensitivity tests. Athletes may or may not demonstrate superior visual acuity and contrast sensitivity compared with age-matched nonathlete populations, and the optical quality of their eyes may be similar. Dynamic visual acuity in athletes and their performance are typically superior to those of nonathletes. How these differences relate to on-field performance is not known. Other changes to the visual system because of refractive surgery or contact lens wear may increase higher order aberrations and reduce low-contrast visual acuity. The ability to improve already-normal visual acuity is unclear although contrast sensitivity can improve with fast-paced video games. Tinted contact lenses help reduce discomfort glare and speed up adaptation but do not have an appreciable effect on visual acuity and contrast sensitivity.
Conclusion:
The use of valid and repeatable visual acuity and contrast sensitivity tests is essential for measuring the differences in visual performance among athletes and nonathletes. The development of a standardized dynamic visual acuity test is needed as are well-controlled scientific studies to evaluate the benefits of sports vision training.
To determine boundary values of test-retest reliability and sensitivity to acuity change that are unlikely to be exceeded in any clinical situation, for a popular visual acuity chart (Lighthouse/ETDRS) with three scoring methods; to discuss general methodological issues associated with statistical accuracy of optotype chart testing; and to link measures of test reliability to measures of sensitivity to change.
Five highly practiced subjects were tested using a computer-controlled acuity testing system in a procedure designed to reduce measurement error. Subjects read the computerized chart 156 times, yielding a sample of 78 test-retest comparisons.
Under conditions likely to minimize variability, visual acuity may, with 95% confidence, be ascertained only within +/- 0.1 log units, using this chart with the recommended letter-by-letter scoring. Detecting a significant change in visual acuity requires about +/- 0.14 log units for the same degree of confidence.
These measurements may be viewed as approaching the upper limit of reliability of this letter chart. Reliability probably is considerably less in typical usage.
To evaluate quantitatively the effects of tinted spectacle lenses on visual performance in individuals without visual pathology.
Twenty-five subjects were assessed by measuring contrast sensitivity with and without glare. Gray, brown, yellow, green, purple, and blue lens tints were evaluated. Measurements were repeated with each lens tint and with a clear lens, and the order was counterbalanced within and between subjects. Glare was induced with a modified brightness acuity tester.
All subjects demonstrated an increase in contrast thresholds under glare conditions for all lens tints. However, purple and blue lens tints resulted in the least amount of contrast threshold increase; the yellow lens tint resulted in the largest contrast threshold increase.
Purple and blue lens tints may improve contrast sensitivity in control subjects under glare conditions.
It has been suggested that contact lens wear improves the visual function of patients with visual loss from congenital nystagmus. In this study, four patients with congenital nystagmus had two evaluations separated by at least one week (one with spectacles, one with contact lenses) including visual acuity, contrast sensitivity, oscillopsia scale, quality of life questionnaire (NEI VFQ-25), and eye movement recording with an infrared tracking system. All patients subjectively preferred contact lenses to spectacles. Their contrast sensitivity and VFQ-25 scores were improved with contact lenses compared with spectacles alone. Several parameters of nystagmus showed no change in two patients, worsening in one patient and improvement in one patient. This suggests that much of the clinical improvement observed in our patients may result from a better optical correction of their refractive error with contact lenses than with spectacles, rather than from a true damping effect of the nystagmus by contact lenses.
It has been suggested that contact lens wear improves the visual function of patients with visual loss from congenital nystagmus. In this study, four patients with congenital nystagmus had two evaluations separated by at least one week (one with spectacles, one with contact lenses) including visual acuity, contrast sensitivity, oscillopsia scale, quality of life questionnaire (NEI VFQ-25), and eye movement recording with an infrared tracking system. All patients subjectively preferred contact lenses to spectacles. Their contrast sensitivity and VFQ-25 scores were improved with contact lenses compared with spectacles alone. Several parameters of nystagmus showed no change in two patients, worsening in one patient and improvement in one patient. This suggests that much of the clinical improvement observed in our patients may result from a better optical correction of their refractive error with contact lenses than with spectacles, rather than from a true damping effect of the nystagmus by contact lenses.
Yellow filter glasses, often sold as "antifog" or "safety" glasses at department stores and other retail outlets, are claimed to improve contrast sensitivity and the yield of visually perceived objects, particularly under poor conditions (e.g., fog, rain and twilight), by enhancing contrast. These claims were tested in 15 healthy subjects (30 eyes) aged 26 to 58 (mean 42.5) years with the Vision Contrast Test System (VCTS 6500), first with and then without yellow filter glasses. Testing was done with commercial antifog glasses and frame-mounted, hand-held filter glasses of CR (Columbia resin) 39 quality with a yellow tint made by an optician. Contrast sensitivity was found to be significantly improved with yellow filter glasses (p less than 0.0001). The use of yellow filter glasses may safely be recommended to patients who report subjective improvement in contrast vision with such glasses.
Contrast sensitivity testing reveals visual deficits not detected by standard acuity tests, providing a more sensitive measure of visual performance. Sine wave contrast sensitivity functions were examined for spectacle and contract lens correction of keratoconic eyes after penetrating keratoplasty (PKP). Contrast sensitivity was significantly higher for middle and high spatial frequencies with a rigid gas permeable contact lens than with glasses, even when Snellen acuity was identical for both forms of correction. Contrast performance correlated with subjective assessments of vision quality. This may be related to the quality of the keratometry mire images and suggests that mild irregularities in graft contour may be affecting contrast sensitivity. When considering the options for optical correction of grafted eyes, an evaluation of contrast sensitivity may help determine whether contact lens correction would optimize visual performance.
The visual performances of eight low myopic subjects (-2 D to -7 D) and eight high myopic subjects (greater than -7 D) with normal visual acuities were analyzed by contrast sensitivity testing with both spectacle and contact lens corrections to determine if any differences in function exist between those groups. Statistically significant (p = 0.0382) contrast sensitivity losses, particularly at the higher spatial frequencies, were found for the high myopic subjects when corrected with spectacles. However, with contact lens correction, no statistically significant overall difference between the two groups was evident (p = 0.5083). We believe that these results confirm for highly myopic subjects the lack of any consistently present loss of resolution. The differences with spectacle correction are attributable to the nature of the optical correction.
Contrast sensitivity (CS) has recently emerged as an important predictor of visual performance. Few studies, however, have been published involving CS and its role in vision for sport. The purpose of this investigation was to determine if significant differences occurred in CS between female professional and collegiate tennis players who wore daily-wear soft contact lenses (N = 10) and those players who wore no corrective lenses (N = 10) in competition as measured by the Stereo Optical Optec 2000 Vision Tester. Subjects were between the ages of 18 and 37 years. Mean ages were 21.76 (+/- 4.018) and 25.40 (+/- 5.379) years for those wearing lenses and those not, respectively. Each subject was preliminarily screened for SVA-distance, lateral/vertical phorias, stereopsis, and color perception. All subjects were within accepted limits. CS was assessed at 1.5, 3, 6, 12, and 18 cycles per degree (cpd). Each subject was assessed monocularly; eye initially assessed was determined randomly. A 2 x 2 factorial analysis of variance (alpha = .05) was used to analyze data. No significant differences were found between eyes. Significant differences were found at 3, 6, 12, and 18 cpd. It may be concluded that those female professional and collegiate tennis players wearing no corrective lenses were significantly higher in CS at intermittent and high spatial frequencies than those who wore daily-wear soft contact lenses in competition.
Special-effect contact lenses (opaque, tinted soft contact lenses that incorporate decorative images such as "cateyes," stars, or hearts to alter eye color and structure) have become increasingly popular. The purpose of this study was to investigate whether such lenses impair visual function.
A clear soft contact lens and a special-effect soft contact lens (Crazy lens,) were fit in changing sequence in nine healthy subjects. The parameters studied included: visual acuity, contrast sensitivity (with and without glare), visual field, and mesopic vision (with and without glare).
The following parameters displayed a statistically significant difference (P < 0.05). Visual acuity was decreased to 0.9 +/- 0.23 in the Crazy lens group as compared with 1.2 +/- 0.13 in the clear lens group. Goldmann visual field displayed a significant constriction of the isopters: III/4, I/4, and I/3. Mesopic vision without glare was reduced from 1:2.5 to 1:7.4. Contrast sensitivity was significantly reduced in a photopic condition with and without glare and in a scotopic condition without glare. Furthermore, the special-effect lenses were associated with a decrease in lens wearing comfort.
Special-effect contact lenses were associated with a reduction of many visual functions, including visual acuity and contrast sensitivity. For some wearers this may interfere with activities where excellent vision is crucial, such as driving a car.
to measure the contrast sensitivity function of varying degrees of myopia with two types of optical correction (spectacle lens and contact lens).
One hundred and five myopic eyes and twenty-eight emmetropic eyes were collected. The myopic group included 105 eyes corrected with spectacle lenses and 71 eyes of them corrected with contact lenses, too; all had corrected vision acuity of 20/20 or better. The myopic eyes were divided into four groups: group 1 (-1D to -3D), low myopia; group 2 (-3.25D to -6D), medium myopia; group 3 (-6.25D to -12D), high myopia; and group 4 (> -12D), severe myopia. Spatial contrast sensitivity was measured using the OPTEC 2000 Contrast Sensitivity System.
In groups 1 and 2, no statistically significant difference was found between myopes and emmetropes. In group 3, statistically significant loss of contrast sensitivity at higher spatial frequencies was found for myopic subjects corrected with spectacle lens, but not for myopes corrected with contact lens. In group 4, myopic subjects corrected with spectacle lenses showed significantly reduced contrast sensitivity function at all spatial frequencies; subjects corrected with contact lenses showed statistical sensitivity losses at 6, 12, 18 cycle/degree spatial frequencies.
1. We may suppose that low and medium myopes (groups 1 and 2), who showed normal contrast sensitivity functions, had no retinal dysfunction. 2. For high myopes, contact lens correction could reduce optical defocus and improve contrast sensitivity function in high spatial frequencies. 3. As retinal function disturbances occurred in severe myopes, the diminished contrast sensitivity was not fully compensated by contact lens correction. 4. Loss of contrast sensitivity might be interpreted as evidence for early retinal function disruption before retinal pathological events occur in severe myopes.
The purpose of the present work was to study the effect on visual performance of wearing disposable soft tinted contact lenses for cosmetic purposes. Parameters such as contrast sensitivity (Vistech 6000), colour vision (Farnsworth-Munsell 100-Hue colour test), visual fields (static Goldmann perimetry) and subjective vision (what the wearer feels while wearing the lenses) were studied under different illumination levels in order to check for possible vision losses while wearing these contact lenses at low illumination levels. Sixteen emmetropic subjects were fitted consecutively with seven pairs of different colour lenses (Optima Colors lenses by Bausch & Lomb), and the experimental parameters were measured under four different illumination levels (60, 6, 1, and 0.1 cd/m2; but 15 and 0.3 cd/m2 for the static perimetry) The results obtained showed no statistically significant differences in visual performance between wearing the lenses and not wearing them (p > 0.01), except for the static perimetry, in which statistically significant differences (p < 0.01) occur at eccentricities greater than 30 degrees.
To investigate the effects of daily wear opaquely tinted hydrogel soft contact lenses on contrast sensitivity functions, as measured using the Pelli-Robson chart viewed at 1 meter.
Contrast sensitivity was measured in 48 healthy individuals before and 6 hours after soft contact lens wear. Twenty-four subjects used clear soft contact lenses and 24 used tinted soft contact lenses.
The contrast sensitivity scores were significantly decreased monocularly and binocularly (P = 0.000 and P = 0.002, respectively) in the colored contact lens group whereas there were no significant changes in the clear contact lens group (P = 0.317 and P = 0.317, respectively).
Color-tinted contact lenses were associated with a reduction of contrast sensitivity function. Therefore, those who wear colored contact lenses should be informed about the possible consequences of tinted contact lens wearing.
A body of clinical and laboratory evidence suggests that tinted spectacle lenses may have an effect on visual performance. The aim of this study was to quantify the effects of spectacle lens tint on the visual performance of 25 subjects with cataracts.
Cataracts were scored based on best-corrected acuity and by comparison with the Lens Opacity Classification System (LOCS III) plates. Visual performance was assessed by measuring contrast sensitivity with and without glare (Morphonome software version 4.0). The effect of gray, brown, yellow, green and purple tinting was evaluated.
All subjects demonstrated an increase in contrast thresholds under glare conditions regardless of lens tint. However, brown and yellow lens tints resulted in the least amount of contrast threshold increase. Gray lens tint resulted in the largest contrast threshold increase.
Individuals with lenticular changes may benefit from brown or yellow spectacle lenses under glare conditions.
In this investigation the quality of two types of optical correction, hydrogel contact lenses and ophthalmic lenses, was compared by measuring the modulation transfer function (MTF) of the correcting lens plus visual optics system using an objective method. A merit function was defined in order to allow the direct comparison between the optical performance with the two corrections. A study on 10 subjects was undertaken, measuring the MTF of both corrections by using the double pass method. The results show that the optical quality of contact lenses was higher than that with ophthalmic lenses. The contrast sensitivity function (CSF) and visual acuity (VA) were determined as subjective parameters of visual performance.