Blue-Light Filtering Spectacle Lenses: Optical and Clinical Performances Amber lenses to block blue light and improve sleep: a randomized trial. Effect of blue-blocking glasses in major depressive disorder with sleep onset insomnia: A randomized, double-blind, placebo-controlled study Effect of Blue Light–Reducing Eye Glasses on Critical Flicker Frequency Short-Wavelength Light-Blocking Eyeglasses Attenuate Symptoms of Eye Fatigue. Attenuating Photostress and Glare Disability in Pseudophakic Patients through the Addition of a Short-Wave Absorbing Filter Effect of variable tinted spectacle lenses on visual performance in control subjects. Blue light filtering intraocular lenses in phacoemulsification cataract surgery. Benefit of coloured lenses for age-related macular degeneration. Wavelength-dependent effects of evening light exposure on sleep architecture and sleep EEG power density in men. Sleep disturbances are related to decreased transmission of blue light to the retina caused by lens yellowing. Double-masked placebo-controlled trial of precision spectral filters in children who use coloured overlays. Blue-enriched white light in the workplace improves self-reported alertness, performance and sleep quality. Clinical results of the blue‐light filtering AcrySof Natural foldable acrylic intraocular lens D‐15 Performance with Short Wavelength Absorbing Filters in Normals Acute exposure to evening blue-enriched light impacts on human sleep. Retinal function assessment of trypan blue versus indocyanine green assisted internal limiting membrane peeling during macular hole surgery.
Purpose s To evaluate the optical performance of blue-light filtering spectacle lenses and investigate whether a reduction in blue light transmission affects visual performance and sleep quality . Methods Experiment 1 : The relative changes in phototoxicity , scotopic sensitivity , and melatonin suppression of five blue-light filtering plano spectacle lenses  were calculated based on their spectral transmittances measured by a spectrophotometer . Experiment 2 : A pseudo-r and omized controlled study was conducted to evaluate the clinical performance of two blue-light filtering spectacle lenses ( BF : blue-filtering anti-reflection coating ; BT : brown-tinted ) with a regular clear lens ( AR ) serving as a control . A total of eighty computer users were recruited from two age cohorts ( young adults : 18–30 yrs , middle-aged adults : 40–55 yrs ) .  Contrast sensitivity under st and ard and glare conditions , and colour discrimination were measured using st and ard clinical tests . After one month of lens wear , subjective ratings of lens performance were collected by question naire . Results All tested blue-light filtering spectacle lenses theoretically reduced the calculated phototoxicity by 10.6 % to 23.6 % . Although use of the blue-light filters also decreased scotopic sensitivity by 2.4 % to 9.6 % , and melatonin suppression by 5.8 % to 15.0 % , over 70 % of the participants could not detect these optical changes . Our clinical tests revealed no significant decrease in contrast sensitivity either with ( 95 % confidence intervals [ CI ] : AR – BT [ –0.05 , 0.05 ] ; AR – BF [ –0.05 , 0.06 ] ; BT – BF [ –0.06 , 0.06 ] ) or without glare ( 95 % CI : AR – BT [ –0.01 , 0.03 ] ; AR – BF [ –0.01 , 0.03 ] ; BT – BF [ –0.02 , 0.02 ] ) and colour discrimination ( 95 % CI : AR – BT [ –9.07 , 1.02 ] ; AR – BF [ –7.06 , 4.46 ] ; BT – BF [ –3.12 , 8.57 ] ) . Conclusion Blue-light filtering spectacle lenses can partially filter high-energy short-wavelength light without substantially degrading visual performance and sleep quality . These lenses may serve as a supplementary option for protecting the retina from potential blue-light hazard . Trial Registration Clinical Trials.gov All light is not equal : blue wavelengths are the most potent portion of the visible electromagnetic spectrum for circadian regulation . Therefore , blocking blue light could create a form of physiologic darkness . Because the timing and quantity of light and darkness both affect sleep , evening use of amber lenses to block blue light might affect sleep quality . Mood is also affected by light and sleep ; therefore , mood might be affected by blue light blockade . In this study , 20 adult volunteers were r and omized to wear either blue-blocking ( amber ) or yellow-tinted ( blocking ultraviolet only ) safety glasses for 3 h prior to sleep . Participants completed sleep diaries during a one-week baseline assessment and two weeks ' use of glasses . Outcome measures were subjective : change in overall sleep quality and positive/negative affect . Results demonstrated that sleep quality at study outset was poorer in the amber lens than the control group . Two- by three-way ANOVA revealed significant ( p < .001 ) interaction between quality of sleep over the three weeks and experimental condition . At the end of the study , the amber lens group experienced significant ( p < .001 ) improvement in sleep quality relative to the control group and positive affect ( p = .005 ) . Mood also improved significantly relative to controls . A replication with more detailed data on the subjects ' circadian baseline and objective outcome measures is warranted ABSTRACT Blue wavelengths form the portion of the visible electromagnetic spectrum that most potently regulates circadian rhythm . We hypothesized that wearing blue-blocking ( BB ) glasses in the evening may influence circadian rhythm disturbances in patients with major depressive disorder ( MDD ) , result ing in improved sleep and mood . We used a r and omized placebo-controlled double-blinded design . Patients with MDD with sleep onset insomnia were r and omly assigned to wearing either BB glasses or clear glasses ( placebo ) . Patients were instructed to wear the glasses from 20:00 hours until bedtime for 2 weeks . We assessed sleep state ( sleep quality on a visual analog scale , the Morningness – Eveningness Question naire [ MEQ ] , and a sleep diary ) and depressive symptoms at baseline and after 2 weeks . Data were analyzed with a full analysis set . In total , 20 patients were r and omly assigned to the BB and placebo groups ( BB group , n = 10 ; placebo group , n = 10 ) . There were three dropouts ( BB group , n = 1 ; placebo group , n = 2 ) . At baseline , sleep quality , sleep latency ( assessed via a sleep diary ) , and antipsychotics use differed between the groups . To take account of these differences , the baseline sleep state or depressive symptoms and antipsychotics use were used as covariates in the later analysis . The change scores for sleep quality did not show a significant improvement in the BB group compared with the placebo group ( mean [ st and ard deviation , SD ] scores for BB versus placebo : 36.1 [ 31.7 ] versus 16.2 [ 15.1 ] , p = 0.43 ) , although half of the BB group showed a clear improvement in sleep quality . The change in MEQ scores did not significantly differ between the groups ( p = 0.14 ) , although there was a trend of a shift to morning type in the BB group ( 3.10 [ 4.95 ] points ) and to evening type in the placebo group ( 0.50 [ 3.89 ] points ) . There were no statistically significant changes in depressive symptoms in either group . Across both groups , 40 % of the participants reported pain or discomfort from wearing the glasses , which were available in only one size . Thus , the failure to find significant differences may have result ed from the glasses used in this study . Glasses fitted to individual patients may improve efficacy and safety . Replication of the study with a larger sample size and size-adjustable glasses is needed Purpose This study aims to evaluate the effect of blocking short-wavelength light on critical flicker frequency ( CFF ) . Design This study is a prospect i ve clinical study . Methods Thirty-three participants ( 17 men and 16 women ; age range , 28–39 years ) were divided into 3 groups . Each group wore 1 of 3 types of lenses while performing an intensive computer task for 2 hours . To evaluate the effect of blocking short-wavelength light before and after the task , we measured the CFF and evaluated subjective question naires . We used the analysis of variance test to examine whether the type of lenses tested affected any of the visual fatigue-related parameters . Results The type of lens worn significantly affected the CFF ; however , answers to the subjective question naires did not differ significantly between the groups . Two of the 13 question items showed a statistical difference between lens transparency and increase in the CFF ( lens 3 > lens 2 > lens 1 ) . Conclusions The higher the blocking effect of the lens , the lower the reduction in the CFF , suggesting that blocking short-wavelength light can reduce eye fatigue Purpose The purpose of this study was to determine whether subjects who wear short wavelength-blocking eyeglasses during computer tasks exhibit less visual fatigue and report fewer symptoms of visual discomfort than subjects wearing eyeglasses with clear lenses . Methods A total of 36 healthy subjects ( 20 male ; 16 female ) was r and omized to wearing no-block , low-blocking , or high-blocking eyeglasses while performing a 2-hour computer task . A masked grade r measured critical flicker fusion frequency ( CFF ) as a metric of eye fatigue and evaluated symptoms of eye strain with a 15-item question naire before and after computer use . Results We found that the change in CFF after the computer task was significantly more positive ( i.e. , less eye fatigue ) in the high-block versus the no-block ( P = 0.027 ) and low-block ( P = 0.008 ) groups . Moreover , r and om assignment to the high-block group but not to the low-block group predicted a more positive change in CFF ( i.e. , less eye fatigue ) following the computer task ( adjusted β = 2.310 ; P = 0.002 ) . Additionally , subjects wearing high-blocking eyeglasses reported significantly less feeling pain around/inside the eye ( P = 0.0063 ) , less feeling that the eyes were heavy ( P = 0.0189 ) , and less feeling that the eyes were itchy ( P = 0.0043 ) following the computer task , when compared to subjects not wearing high-blocking lenses . Conclusions Our results support the hypothesis that short-wavelength light-blocking eyeglasses may reduce eye strain associated with computer use based on a physiologic correlate of eye fatigue and on subjects ' reporting of symptoms typically associated with eye strain To evaluate the effects of filtering short wavelength light on visual performance under intense light conditions among pseudophakic patients previously implanted with a clear intraocular lens ( IOL ) .  This was a patient-masked , r and omized crossover study conducted at 6 clinical sites in the United States between September 2013 and January 2014 . One hundred fifty-four bilaterally pseudophakic patients were recruited .  Photostress recovery time and glare disability thresholds were measured with clip-on blue-light-filtering and placebo ( clear ; no blue-light filtration ) glasses worn over patients ' habitual correction . Photostress recovery time was quantified as the time necessary to regain sight of a grating target after intense light exposure . Glare disability threshold was assessed as the intensity of a white-light annulus necessary to obscure a central target . The order of filter used and test eye were r and omized across patients . Photostress recovery time and glare disability thresholds were significantly improved ( both P < 0.0001 ) when patients used blue-light-filtering glasses compared with clear , nonfiltering glasses . Compared with a nonfiltering placebo , adding a clip-on blue-absorbing filter to the glasses of pseudophakic patients implanted with clear IOLs significantly increased their ability to cope with glare and to recover normal viewing after an intensive photostress . This result implies that IOL design s with blue-light-filtering characteristics may be beneficial under intense light conditions PURPOSE To evaluate quantitatively the effects of tinted spectacle lenses on visual performance in individuals without visual pathology . METHODS 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 . RESULTS All subjects demonstrated an increase in contrast thresholds under glare conditions for all lens tints . However , purple and blue lens tints result ed in the least amount of contrast threshold increase ; the yellow lens tint result ed in the largest contrast threshold increase . CONCLUSIONS Purple and blue lens tints may improve contrast sensitivity in control subjects under glare conditions Blue light can damage retina and cause age related macular degeneration . After cataract surgery and lens removal retina stays unprotected . Blue light filtering intraocular lenses ( IOL ) increase protection of the retina . In our prospect i ve study we investigated clinical results after bilateral implantation of Acrysof Natural IOL to 30 patients ( N = 60 eyes ) . In a control group ( N = 60 eyes , 30 patients ) ,  st and ard acrysof IOL was implanted bilaterally . Uncorrected visual acuity ( UCVA ) , best corrected visual acuity ( BCVA ) and Nd YAG laser capsulotomy rate were measured and compared with control group . Subjective patient 's satisfaction and subjective colour perception were also investigated . There was no significant difference in UCVA , BCVA and Nd YAG laser capsulotomy rate between the two groups . High patient 's satisfaction was noticed ( 96.7 % of patients would implant Acrysof Natural IOL again ) . Acrysof Natural IOL enables good visual acuity VA , low rate of Nd YAG laser capsulotomy and high patient 's satisfaction without colour perception disturbances PURPOSE To evaluate and compare the functional and perceived benefits of wearing coloured lenses by patients with age-related macular degeneration ( ARMD ) . METHOD Ten subjects with early ARMD and five elderly controls wore a selection of NoIR wrap-around coloured lenses ( yellow 29.7 % light transmission , orange 22.9 % , red 16.8 % and grey 10.3 % ) , each for a duration of 7 days . Contrast sensitivity , colour vision , visual acuity , the effect of glare and peripheral sensitivity were measured for each lens and compared with a control ( no lens ) condition . Subjective ratings of visual performance were also scored . RESULTS Compared with the no filter condition , red and grey lenses reduced contrast sensitivity whereas yellow and orange lenses increased contrast sensitivity . These objective changes were supported by subjective ratings in subjects with ARMD . Grey lenses reduced the loss of contrast sensitivity usually suffered in the presence of glare , whereas visual acuity and peripheral sensitivity decreased with red lenses . Colour vision became distorted with red lenses in control subjects , but was relatively unaffected by the use of coloured lenses in subjects with ARMD . CONCLUSIONS The subjective benefit of coloured lenses appears to be due to a minor enhancement of contrast sensitivity Light strongly influences the circadian timing system in humans via non-image-forming photoreceptors in the retinal ganglion cells . Their spectral sensitivity is highest in the short-wavelength range of the visible light spectrum as demonstrated by melatonin suppression , circadian phase shifting , acute physiological responses , and subjective alertness . We tested the impact of short wavelength light ( 460 nm ) on sleep EEG power spectra and sleep architecture . We hypothesized that its acute action on sleep is similar in magnitude to reported effects for polychromatic light at higher intensities and stronger than longer wavelength light ( 550 nm ) . The  sleep EEGs  of eight young men were analyzed after 2-h evening exposure to blue ( 460 nm ) and green ( 550 nm ) light of equal photon densities ( 2.8 x 10(13 ) photons x cm(-2 ) x s(-1 ) ) and to dark ( 0 lux ) under constant posture conditions . The time course of EEG slow-wave activity ( SWA ; 0.75 - 4.5 Hz ) across sleep cycles after blue light at 460 nm was changed such that SWA was slightly reduced in the first and significantly increased during the third sleep cycle in parietal and occipital brain regions . Moreover , blue light significantly shortened rapid eye movement ( REM ) sleep duration during these two sleep cycles . Thus the light effects on the dynamics of SWA and REM sleep duration s were blue shifted relative to the three-cone visual photopic system probably mediated by the circadian , non-image-forming visual system . Our results can be interpreted in terms of an induction of a circadian phase delay and /or repercussions of a stronger alerting effect after blue light , persisting into the sleep episode STUDY OBJECTIVES Sleep pattern and circadian rhythms are regulated via the retinohypothalamic tract in response to stimulation of a subset of retinal ganglion cells , predominantly by blue light ( 450 - 490 nm ) . With age , the transmission of blue light to the retina is reduced because of the aging process of the human lens , and this may impair the photoentrainment of circadian rhythm leading to sleep disorders . The aim of the study was to examine the association between lens aging and sleep disorders . DESIGN Cross-sectional population based study . SETTING The study was performed at the Research Center for Prevention and Health , Glostrup Hospital , Denmark and at the Department of Ophthalmology , Herlev Hospital , Denmark . PARTICIPANTS An age- and sex-stratified sample of 970 persons aged 30 to 60 years of age drawn from a sample r and omly selected from the background population . INTERVENTIONS Not applicable . MEASUREMENTS AND RESULTS Sleep disturbances were evaluated by a combination of question naire and the use of prescription sleeping medication . Lens aging ( transmission and yellowing ) was measured objective ly by lens autofluorometry . The risk of sleep disturbances was significantly increased when the transmission of blue light to the retina was low , even after correction for the effect of age and other confounding factors such as smoking habits , diabetes mellitus , gender , and the risk of ischemic heart disease ( P < 0.0001 ) . CONCLUSIONS Filtration of blue light by the aging lens was significantly associated with an increased risk of sleep disturbances . We propose that this is a result of disturbance of photoentrainment of circadian rhythms We selected 68 children who reported benefit from individually chosen sheets of coloured plastic placed upon the page when reading , and who used these regularly without prompting . These children viewed text illuminated by coloured light in an apparatus that allowed the separate manipulation of hue ( colour ) and saturation ( depth of colour ) , at constant luminance . Many of the children reported improvements in perception when the light had a chromaticity within a limited range , which was different for each individual . A pair of plastic spectacle lenses ( ' experimental ' lenses ) was dyed so as to provide the appropriate chromaticity under conventional white ( F3 ) fluorescent light . An additional pair was prepared having very similar colour but with a chromaticity outside the range in which perception was reported to improve ( ' control ' lenses ) . Each pair was provided for 1 month in r and om order . The children kept diaries ( 36 completed ) recording symptoms of eye-strain and headache . The children and those responsible for their assessment were unable reliably to distinguish ' experimental ' from ' control ' lenses . Nevertheless , symptoms were less frequent on days when the ' experimental ' lenses were worn ( P < 0.003 ) OBJECTIVES Specifications and st and ards for lighting installations in occupational setting s are based on the spectral sensitivity of the classical visual system and do not take into account the recently discovered melanopsin-based , blue-light-sensitive photoreceptive system . The authors investigated the effects of exposure to blue-enriched white light during daytime workhours in an office setting . METHODS The experiment was conducted on 104 white-collar workers on two office floors . After baseline assessment s under existing lighting conditions , every participant was exposed to two new lighting conditions , each lasting 4 weeks . One consisted of blue-enriched white light ( 17 000 K ) and the other of white light ( 4000 K ) . The order was balanced between the floors . Question naire and rating scales were used to assess alertness , mood , sleep quality , performance , mental effort , headache and eye strain , and mood throughout the 8-week intervention . RESULTS Altogether 94 participants [ mean age 36.4 ( SD 10.2 ) years ] were included in the analysis . Compared with white light ( 4000 K ) , blue-enriched white light ( 17 000 K ) improved the subjective measures of alertness ( P<0.0001 ) , positive mood ( P=0.0001 ) , performance ( P<0.0001 ) , evening fatigue ( P=0.0001 ) , irritability ( P=0.004 ) , concentration ( P<0.0001 ) , and eye discomfort ( P=0.002 ) . Daytime sleepiness was reduced ( P=0.0001 ) , and the quality of subjective nocturnal sleep ( P=0.016 ) was improved under blue-enriched white light . When the participants ' expectation about the effect of the light treatments was entered into the analysis as a covariate , significant effects persisted for performance , alertness , evening fatigue , irritability , difficulty focusing , concentrating , and blurred vision . CONCLUSIONS Exposure to blue-enriched white light during daytime workhours improves subjective alertness , performance , and evening fatigue PURPOSE : To verify the safety and effectiveness of the new AcrySof Natural ( Alcon Laboratories , Inc. ) blue‐light filtering intraocular lens ( IOL ) , which was design ed to achieve a light‐transmission spectrum similar to that of the natural human crystalline lens . SETTING : Multicenter U.S. clinical trial . METHODS : In a prospect i ve r and omized patient‐masked multicenter study , 150 patients received the AcrySof Natural IOL and 147 patients received the AcrySof single‐piece IOL as a control . Patients with bilateral age‐related cataracts who were willing and able to wait at least 30 days between cataract procedures and had verified normal preoperative color vision were eligible for the study . St and ardized surgery included a 4.0 to 5.0 mm capsulorhexis and phacoemulsification . All lenses were inserted in the capsular bag , with verification of in‐the‐bag placement of both haptics . In all bilateral implantation cases , the same model IOL was used in each eye . Postoperatively , contrast sensitivity and color perception were measured up to 180 days and up to 1 year ( for visual acuity ) after implantation . RESULTS : No statistically significant differences were discovered between the 2 patient groups in visual acuity , contrast sensitivity evaluated under mesopic and photopic conditions , or the number of patients who passed the Farnsworth D‐15 color perception test . There were no lens‐related adverse events in either group . CONCLUSIONS : The blue‐light filtering AcrySof Natural IOL was equivalent to the conventional AcrySof lens in terms of postoperative visual performance . Additional long‐term clinical studies should show whether the IOL actually provides the theoretical benefits to retinal health ABSTRACT Short wavelength absorbing filters ( SWAF 's ) have become very popular in the prescription and commercial sunglass markets . Like other chromatic filters SWAF 's have the potential to alter color vision . Performance on the Farnsworth Panel D‐15 ( D‐15 ) test was measured to determine whether any of 4 popular SWAF 's , in the form of sunglasses , produced color vision changes in 22 color normal adults . Using st and ard illuminant C , observers were tested under the following conditions : wearing no filter , a 1.0 log unit neutral density filter ( NDF ) , or one of the following SWAF 's : Corning CPF 550 ; NoIR Amber 40 % ; Blu Blocker ; and Vuarnet 4006 . In addition , the Vuarnets were tested outdoors in shaded daylight to determine the effects of increased illumination . The NDF served as the control and had no effect on D‐15 performance . Compared to it , only the Blu Blockers and Vuarnets affected D‐15 cap arrangements for these SWAF 's significantly . Blu Blocker error patterns had no predominant axis , whereas the predominant axis of errors in both Vuarnet conditions was tritan . Results of quantitative analysis performed on three factors confirmed these findings and indicated the Blu Blockers and Vuarnet SWAF 's caused moderate and moderate‐to‐severe levels of color confusion , respectively . Increasing the illumination level improved performance with the Vuarnets , but it remained significantly outside the normal range Light in the short wavelength range ( blue light : 446 - 483 nm ) elicits direct effects on human melatonin secretion , alertness and cognitive performance via non-image-forming photoreceptors . However , the impact of blue-enriched polychromatic light on human sleep architecture and sleep electroencephalographic activity remains fairly unknown . In this study we investigated sleep structure and sleep electroencephalographic characteristics of 30 healthy young participants ( 16 men , 14 women ; age range 20 - 31 years ) following 2 h of evening light exposure to polychromatic light at 6500 K , 2500 K and 3000 K.  Sleep structure across the first three non-rapid eye movement non-rapid eye movement - rapid eye movement sleep cycles did not differ significantly with respect to the light conditions . All-night non-rapid eye movement sleep electroencephalographic power density indicated that exposure to light at 6500 K result ed in a tendency for less frontal non-rapid eye movement electroencephalographic power density , compared to light at 2500 K and 3000 K. The dynamics of non-rapid eye movement electroencephalographic slow wave activity ( 2.0 - 4.0 Hz ) , a functional index of homeostatic sleep pressure , were such that slow wave activity was reduced significantly during the first sleep cycle after light at 6500 K compared to light at 2500 K and 3000 K , particularly in the frontal derivation . Our data suggest that exposure to blue-enriched polychromatic light at relatively low room light levels impacts upon homeostatic sleep regulation , as indexed by reduction in frontal slow wave activity during the first non-rapid eye movement episode OBJECTIVE To compare multifocal electroretinography ( mfERG ) retinal function and the anatomical and visual outcomes of macular hole surgery performed with indocyanine green ( ICG ) or trypan blue ( TB ) . DESIGN Prospect i ve , r and omized study . PARTICIPANTS Twenty-five eyes of 24 patients . METHODS Patients underwent a pars plana vitrectomy with removal of the internal limiting membrane .  In 14 eyes , internal limiting membrane visualization during macular hole repair was performed using TB , and ICG was used in 11 eyes . The examination protocol ( performed before surgery and at 3 weeks , 3 months , 6 months , and 12 months after surgery ) included optical coherence tomography , mfERG ( mfERG-103 hexagons ) , and assessment of best corrected visual acuity ( BCVA )  and contrast sensitivity ( CS ) . RESULTS Closure of macular hole was achieved in 100 % of the cases . In the TB group , P1 amplitude and implicit time improved significantly at 12 months after surgery ( P < 0.05 ) , whereas in the ICG group , significant improvement occurred at both 6 ( P < 0.05 ) and 12 months ( P < 0.01 ) . BCVA improved significantly in both groups at 6 and 12 months ( P < 0.01 ) . Both groups also showed a statistically significant CS improvement at spatial frequency of 6 cycles per degree ( P = 0.01 ) 1 year postoperatively . At 12 months , improvement of P1 amplitude and implicit time , BCVA , and CS was not different between groups . CONCLUSIONS In this study , the use of TB or ICG appears to yield similar improvement in terms of BCVA , CS , and mfERG amplitude and implicit time changes at 12 months
A study involving normal participants found no observed difference in sleep quality .
We found no studies investigating effects on macular structure or function .
We find a lack of high quality evidence to support using BB spectacle lenses for the general population to improve visual performance or sleep quality , alleviate eye fatigue or conserve macular health
PURPOSE Blue-blocking ( BB ) spectacle lenses , which attenuate short-wavelength light , are being marketed to alleviate eyestrain and discomfort when using digital devices , improve sleep quality and potentially confer protection from retinal phototoxicity .
The aim of this review was to investigate the relative benefits and potential harms of these lenses .