Photostress Recovery Time Research Articles

The Effects of Blue Light-Filtering Intraocular Lenses on the Protection and Function of the Visual System.

Filtration of high-energy short-wave visible light (blue light) to improve vision and protect against damage has evolved both in aquatic animals and terrestrial species. In humans, pigments in the inner layer of the macula absorb wavelengths between 400 and 520 nm and function to improve visual performance. In patients who undergo cataract surgery, replacing cataractous lenses with artificial intraocular lenses (IOLs) that do not mimic normal healthy adult lenses could result in preventable negative visual effects, including glare disability. Blue light–filtering (BLF) IOLs were designed to filter short-wave light in addition to ultraviolet light and mimic the natural crystalline lens. Current studies indicate that BLF IOLs may provide protection from blue light–induced retinal damage and slow the development and progression of age-related macular degeneration. Additionally, BLF IOLs have been shown to improve chromatic contrast, reduce photostress recovery time, reduce glare disability and discomfort, and generally improve visual performance under glare conditions. Although a number of concerns have been raised about the relative risks versus the benefits of BLF IOLs, recent studies reported no adverse effects on visual function or contrast under photopic conditions, no long-term effects on color vision, and no detrimental effects on circadian rhythms with BLF IOLs. Based on the current understanding of the field, evidence suggests that BLF IOLs would be returning the eye to a more natural state compared with non-BLF lenses.

Effect of central hole location in phakic intraocular lenses on visual function under progressive headlight glare sources

To analyze the effect of the central hole location in the V4c implantable collamer lens (ICL) on the quality of vision, including progressive headlight glare simulation and quality of life. IOBA-Eye Institute, Valladolid, Spain. Case series. The central hole location was determined by slitlamp and dual Scheimpflug imaging for 6months or more postoperatively. The visual acuity, mesopic contrast sensitivity, halogen glare contrast sensitivity, xenon glare contrast sensitivity, photostress recovery time after glare, de Boer scale, and Quality of Life Impact of Refractive Correction (QIRC) questionnaire results were evaluated. Multiple regression models were used to analyze the effect of the central hole location on parameters using the pupil center and visual axis as references based on Cartesian and polar coordinates. The safety index was 1.13 and the efficacy index, 1.12. Under all testing circumstances, central hole decentration did not affect the visual acuity or contrast sensitivity. With the visual axis as a reference, worse QIRC values were associated with greater upward central hole displacement (P=.03) and a lower polar angle value (P=.008); also, halogen glare discomfort was greater with a higher radius (P=.04). Using the pupil center as a reference, greater nasal central hole decentration was associated with longer xenon glare photostress recovery time (P=.002). Implantation of the ICL with a central hole yielded excellent visual outcomes, even under increasing glare sources, regardless of the hole's location. However, hole decentration might affect patient-perceived quality of life, bothersome halogen glare, and longer xenon glare photostress recovery time. Such complaints after the early postoperative period might be managed with discrete ICL centration if the central hole is decentered upward or nasally.

An Investigation of the Role of Macular Pigment in Attenuating Photostress through Comparison between Blue and Green Photostress Recovery Times

ABSTRACTPurpose: Photostress recovery time (PSRT) is the time required for the macula to return to its normal functioning after the bleaching of cone photopigments due to light exposure, usually white. This work investigates the role of macular pigment (MP) as an optical filter that attenuates photostress by analyses of PSRT at different wavelengths.Methods: Thirty-nine subjects (19–28 years) were exposed to blue/green photostress varying in irradiance. During photostress, pupil constriction (Cp) was measured. Twenty-seven subjects (20–27 years) were exposed to white photostress. After 25 s of photostress, the time (PSRT) required to read correctly a 0.2 logMAR letter was measured. Correlation was studied between PSRT, CP, and irradiance. Statistical significance of differences between PSRTs was evaluated at Log(irradiance(quanta s−1 cm−2)) = 14 by Student’s t statistics.Results: Cp and PSRT were found linearly correlated to Log(irradiance) for blue, green, and white. At Log(irradiance(quanta s−1 cm−2)) = 14, blue and green mean PSRTs resulted different (p < 0.001) with 3.8 ± 0.8 s and 6.7 ± 1.7 s, respectively. After correcting irradiance for the optical absorption of MP, mean blue PSRT became 6.6 ± 0.8 s, at the logarithm of MP-corrected irradiance in quanta s−1 cm−2 equal to 14 (p = 0.571 compared to green PSRT). For white light, at the logarithm of MP-corrected irradiance in quanta s−1 cm−2 equal to 14, mean PSRT was 7.5 ± 2.2 s, not significantly different from blue and green PSRT (p > 0.05).Conclusions: MP plays the role of an optical filter attenuating photostress. PSRT was substantially proportional to the number of incident photons corrected for the MP optical absorption, regardless of their wavelength.

Macular pigment is associated with glare-affected visual function and central visual field loss in glaucoma

AimTo evaluate the relationship between macular pigment optical density (MPOD) and glare disability in open-angle glaucoma.MethodsA cross-sectional analysis of baseline data (88 subjects; median age, 67 (range 36–84) years) collected...

The effects of photochromic lenses on visual performance

BackgroundThe purpose of the current study was to evaluate the effects of filtering by an activated photochromic lens on visual performance in healthy adults. Glare disability, glare discomfort, heterochromatic contrast thresholds and photostress recovery time were assessed.MethodsA subject‐masked, randomised, cross‐over design was employed. Seventy‐five healthy adults were recruited, aged 19 to 73 years (mean = 45.61 ± 13.24 years). Visual functions were measured using three different photochromic lenses that were partially activated with a steady state transmittance of 63 per cent T (Gray1), 71 per cent T (Gray2), and 71 per cent T (Brown). These lenses were compared with a clear (92 per cent transmission) polycarbonate lens. Glare disability was assessed as the intensity of a white (xenon)‐light annulus necessary to obscure a central grating target. Heterochromatic contrast thresholds were measured as absolute thresholds for a monochromatic 570 nm target superimposed on a 460 nm circular background. Glare discomfort was quantified using bio‐imaging of the squint response as well as a Likert‐based self‐report scale. Photostress recovery time was recorded as the time necessary to regain sight of a grating target after intense light exposure. Glare discomfort and photostress recovery were only assessed for the Gray1 lens compared to placebo. Lens order was randomised between subjects and conditions.ResultsAll visual functions measured were significantly improved (p < 0.05) for all of the activated photochromic lenses tested versus the clear lens. In the glare disability and heterochromatic contrast conditions, numeric differences (p < 0.09) were also seen between each of the three different activated photochromic lens types. Glare discomfort and photostress recovery times were improved in the Gray1 condition, as quantified by both the squint and subjective responses (p < 0.05).ConclusionAdding filtering via a photochromic lens significantly increased subjects' abilities to cope with intense broadband and shortwave lighting conditions and to adapt back to normal viewing after being presented with an intense photostressor.

Relationship between macular pigment and visual function in subjects with early age-related macular degeneration

PurposeTo investigate the relationship between macular pigment (MP) and visual function in subjects with early age-related macular degeneration (AMD).Methods121 subjects with early AMD enrolled as part of the Central Retinal...

Photostress recovery time among commercial drivers in Nigeria

Photostress recovery time (PSRT) test is a simple technique used to assess the macular function. Prolonged recovery time is attributed to the delay in regeneration of visual pigments after being bleached with a bright light. In car drivers with macular degeneration, photostress effects from opposing cars may bleach retinal pigments and cause a dramatic drop in visual acuity. The study aims todetermine the prevalence of abnormal PSRT and the association of PSRT with age, visual function and driving safety among commercial drivers in Nigeria.A cross-sectional descriptive study was carried out in Ilorin metropolis, a city in north central Nigeria.Of the estimated 4,729 registered commercial drivers, 327were selected using multistage sampling methods. Structured questionnaire was administered by trained research assistants. PSRT test and visual function tests were carried out by the principal researcher and an assistant. Subject with normal healthy macular function should be able to read the visual acuity line just above the pre-exposure visual acuity line in 50-60 seconds. Patients with a macular problem may have recovery times lasting 1.5 to 3 min or longer. The study revealed a statistically significant association between PSRT and visual acuity as well as colour vision (p<0.05). No association existed between PSRT and age, visual field and driving safety. Majority of the respondents with normal PSRT had fair driving safety. Regular visual screening especially during license renewals may be the most useful tool for the detection of impaired visual function and delayed photo stress recovery time among commercial drivers. Keywords: Photostress, Macular degeneration, Commercial drivers

Multimodal Characterization of Proliferative Diabetic Retinopathy Reveals Alterations in Outer Retinal Function and Structure

To identify changes in retinal function and structure in persons with proliferative diabetic retinopathy (PDR), including the effects of panretinal photocoagulation (PRP). Cross-sectional study. Thirty adults who underwent PRP for PDR, 15 adults with untreated PDR, and 15 age-matched controls. Contrast sensitivity, frequency doubling perimetry (FDP), Humphrey visual fields, photostress recovery, and dark adaptation were assessed. Fundus photography and macular spectral-domain optical coherence tomography (SD OCT) were performed. To quantify retinal layer thicknesses, SD OCT scans were segmented semiautomatically. Visual function measures were compared among patients with PDR and PRP, untreated patients with PDR, and controls. Mean retinal layer thicknesses were compared between groups. Correlation analyses were performed to evaluate associations between visual function measures and retinal layer thicknesses. A significant reduction of FDP mean deviation (MD) was exhibited in PRP-treated patients with PDR (MD ± standard deviation, -8.20±5.76 dB; P < 0.0001) and untreated patients (-5.48±4.48 dB; P < 0.0001) relative to controls (1.07±2.50 dB). Reduced log contrast sensitivity compared with controls (1.80±0.14) also was observed in both PRP-treated patients (1.42±0.17; P < 0.0001) and untreated patients (1.56±0.20; P = 0.001) with PDR. Compared with controls, patients treated with PRP demonstrated increased photostress recovery time (151.02±104.43 vs. 70.64±47.14 seconds; P = 0.001) and dark adaptation speed (12.80±5.15 vs. 9.74±2.56 minutes; P = 0.022). Patients who underwent PRP had diffusely thickened nerve fiber layers (P = 0.024) and diffusely thinned retinal pigment epithelium (RPE) layers (P = 0.009) versus controls. Untreated patients with PDR also had diffusely thinned RPE layers (P = 0.031) compared with controls. Patients with untreated PDR exhibited inner retinal dysfunction, as evidenced by reduced contrast sensitivity and FDP performance, accompanied by alterations in inner and outer retinal structure. Patients who underwent PRP had more profound changes in outer retinal structure and function. Distinguishing the effects of PDR and PRP may guide the development of restorative vision therapies for patients with advanced diabetic retinopathy.

Attenuating Photostress and Glare Disability in Pseudophakic Patients through the Addition of a Short-Wave Absorbing Filter.

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, randomized 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 randomized 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 designs with blue-light-filtering characteristics may be beneficial under intense light conditions.

A double-blind, placebo-controlled study on the effects of lutein and zeaxanthin on photostress recovery, glare disability, and chromatic contrast.

Past studies have shown that higher macular pigment optical density (MPOD) and lutein (L) and zeaxanthin (Z) supplementation are related to improvements in glare disability, photostress recovery, and chromatic contrast. This study assessed those links using a randomized, double-blind, placebo-controlled design. The visual effects of 1 year of supplementing L (10 mg/d) and Z (2 mg/d) were investigated. One hundred fifteen young, healthy subjects were recruited and randomized into the study (58 received placebo, 57 L+Z). Several dependent measures were collected at baseline and then once every 3 months: serum L and Z measured by HPLC chromatography; MPOD measured using customized heterochromatic flicker photometry; photostress recovery assessed by measuring the time needed to recover visual acquisition of a grating target after 30 seconds of an intense xenon white flash exposure; glare disability evaluated as the energy in a surrounding annulus necessary to veil a central grating target; and chromatic contrast assessed by measuring thresholds for a yellow grating target superposed on a 460-nm background. Macular pigment optical density increased significantly versus placebo at all eccentricities (10, 30, 60, and 105 minutes from the center of the macula). Serum L and Z also increased significantly by the first follow-up visit (at 3 months), and remained elevated throughout the intervention period of 1 year. Chromatic contrast and photostress recovery time improved significantly versus placebo. Glare disability was correlated with macular pigment density throughout the study period but did not increase significantly in the treated group. Daily supplementation with L+Z resulted in significant increase in serum levels and MPOD and improvements in chromatic contrast and recovery from photostress. These results are consistent with past studies showing that increasing MPOD leads to improved visual performance. (ClinicalTrials.gov number, NCT00909090.).

SUITABILITY AND REPEATABILITY OF A PHOTOSTRESS RECOVERY TEST DEVICE, THE MACULAR DEGENERATION DETECTOR (MDD-2), FOR DIABETES AND DIABETIC RETINOPATHY ASSESSMENT

Diabetic retinopathy can result in impaired photostress recovery time despite normal visual acuity and fundoscopic appearance. The Macular Degeneration Detector (MDD-2) is a novel flash photostress recovery time device. In this study, we examine the repeatability of the MDD-2 in normal and diabetic subjects. One hundred and ninety one (90 women, 101 men) subjects were recruited and divided into 1 of the 3 study groups (normal controls, n = 40; diabetes no retinopathy, n = 98; nonproliferative diabetic retinopathy, n = 53). Photostress recovery time was measured three times in the study eye using the MDD-2, each measurement separated by a 5-minute interval. Repeated measures analysis of variance revealed no statistically significant learning or fatigue effects on intrameasurement repeatability for any group. Photostress recovery time measures were broadly similar and typically not statistically significantly different between study groups. The coefficient of repeatability reached clinically acceptable levels once the initial photostress recovery time measure, which demonstrated increased variability and latency compared with all subsequent measures, was excluded. The MDD-2 seems to provide repeatable photostress recovery time measurements among naive diabetic subjects. The device does not, however, seem capable of differentiating normal and nonproliferative diabetic eyes, and would not be suitable for inclusion in diabetic retinopathy screening protocol.

눈의 광피로회복시간 검사를 위한 도구의 탐색

Purpose: This study was investigated to find out a useful instrument instead of direct ophthalmoscope for ocular photostress recovery time (PSRT) test. Methods: The PSRT test was performed using direct ophthalmoscope, trans illuminator, pen light, and camera flash for 48 subjects (average age 22.88 years, 96 eyes) who were corrected to 0.8~1.2 of visual acuity. Results: Each mean of PSRT measured by direct ophthalmoscope, trans illuminator, pen light, and camera flash was sec, sec, sec, and sec, respectively. The difference of PSRT between the eyes corrected more than 1.0 and the other eyes corrected under 1.0 of visual acuity was not found significantly. And there was no difference between dominant eyes and nondominant eyes of PSRT. Conclusions: Though the nearest instrument to direct ophthalmoscope was trans illuminator, pen light and camera flash could be the useful instruments for PSRT test.

The microstructural and functional changes in the macula of heavy habitual smokers

To investigate whether heavy habitual smoking affects microstructures and functions of the macula, 45 age- (20-39 years old) and sex-matched adult smokers (≥1 box/day for ≥5 years) and 45 nonsmokers (controls) were enrolled in this case-control study. Central macular thickness (CMT), macular autofluorescent pigment density (MAPD), macular electroretinogram (ERG), and photostress recovery time (PRT) measurements were performed. The mean age of smokers and nonsmokers was 32.9 ± 3.9 and 33.1 ± 4.1 years, respectively (p = 0.43), and smoking duration was 11 ± 5.6 years. CMT in smokers (220 ± 28 μm) and nonsmokers (217.2 ± 31 μm; p = 0.57) was similar. Smokers had lower MAPD values (124.6) than nonsmokers (138.2) (p = 0.010). Multifocal ERG parameters in the central (6°) hexagon were similar in both groups (p > 0.05 for latency and amplitudes of P1 and N1). PRT in smokers and nonsmokers was similar (7.2 ± 1.2 and 7.4 ± 1.9 min, respectively; p = 0.33); however, foveal threshold value (FTV) at the first minute after photostress was statistically higher in smokers (36.1 ± 1.04 dB) than nonsmokers (34.8 ± 1.05 dB) (p = 0.011). We conclude that decreased MAPD and altered response to photostress may be indicative of early nicotine toxicity in microstructurally sound macula of adult chronic smokers.

The Effect of Chronic Smoking on the Pupil and Photostress Recovery Time

Purpose: To determine the effect of chronic smoking on the pupil and photostress recovery time. Methods: Macular adaptation to photostress condition, and mesopic and photopic pupillary responses were measured using automated perimetry (Humprey®), and an OPD device (Nidek), respectively. Forty heavy smokers (smoking ≥1 box/day for the past 5 years at least), and 40 age- and sex-matched nonsmokers were enrolled. All the subjects had full vision and no ocular problems. Results: The baseline foveal threshold value (FTV) before photostress was similar in both groups (p = 0.75). Although photostress recovery times (7.1 ± 1.1 and 7.4 ± 1.3 min) were similar in smokers and nonsmokers (p = 0.30), FTV measured at the first minute after photostress was statistically higher in smokers (36.05 ± 0.98 dB) than nonsmokers (34.7 ± 1.03 dB; p = 0.018). Scotopic pupil sizes in smokers (6.73 ± 0.82 mm) and nonsmokers (6.55 ± 0.62 mm) were similar (p = 0.28); however, photopic pupil size in smokers (5.36 ± 0.73 mm) was different from nonsmokers (4.73 ± 0.58 mm; p = 0.001). Conclusions: Chronic smoking may dilate the pupil, and increases macular FTV immediately after photostress.

A comparative study of the usefulness of color vision, photostress recovery time, and visual evoked potential tests in early detection of ocular toxicity from hydroxychloroquine

Ocular toxicity from hydroxychloroquine (HCQ) is rare, but its potential permanence and severity makes it imperative to employ measures and screening protocols to minimize its occurrence. This study was performed to assess the usefulness of color vision, photo stress recovery time (PSRT), and visual evoked potentials (VEP) in early detection of ocular toxicity of HCQ, in patients with rheumatoid arthritis (RA) and systemic lupus erythematosus (SLE). 86 patients were included in the study and divided into three groups: (1) with history of HCQ use: interventional 1 (Int.1) without fundoscopic changes and Int.2 with fundoscopic changes; and (2) without history of HCQ use, as control. Visual field, color vision, PSRT and VEP results were recorded for all patients and the effect of age, disease duration, treatment duration and cumulative dose of HCQ on each test was assessed in each group. There was a significant relationship among PSRT and age, treatment duration, cumulative dose of HCQ and disease duration (P<0.001 for all). Color vision was normal in all the cases. P100 amplitude was not different between the three groups (P=0.846), but P100 latency was significantly different (P=0.025) and for Int.2 it was greater than the others. The percentage of abnormal visual fields for Int.2 was more than Int.1 and control groups (P=0.002 and P=0.005 respectively), but Int.1 and control groups were not significantly different (P>0.50). In the early stages of maculopathy, P100 latencies of VEP and PSRT are useful predictors of HCQ ocular toxicity. In patients without ocular symptoms and fundoscopic changes, the P100 latency of VEP predicts more precisely than the others.

The effect of Telfaira occidentalis(fluted pumpkin) extract on the photostress recovery time (psrt) of young Nigerian adults

Telfaira Occidentalis (fluted pumpkin) is a vital source of plant vitamin, Zinc and a food antioxidant. The study was designed to determine the effect of Telfaira Occidentalis (T. Occidentalis) extract on the photo-stress recovery time (PSRT) of young Nigerian adults. The PSRT of forty subjects was determined before and after the ingestion of 180ml of the extract in three divide doses of 60ml daily for three days, using photic radiation from an ophthalmoscope on subjects who has a minimum PSRT of 30 seconds (secs). The post-test was measured at 24hrs interval for a period of 72hrs (3days). The results showed reduction in the mean baseline PRST value (48.56secs). The induced values were 45.30secs, 40.67secs, and 35.38secs at 24hrs, 48hrs and 72hrs respectively. This showed a percentage reduction of 6.49%, 16.25% and 26.73% per 24hrs interval.The effect was found to be insignificant (P

Photostress Recovery Time Among Nigerians

Visual impairment may result from a deficiency of the retinal pigment epithelium or macula. Macula photostress test (MPST) is a quantitative estimation of the functional capability and performance reserve of the photoreceptive elements of the macula/retina. The purpose of this study was to determine the Photostress Recovery Time (PSRT) of different age groups in a sample of healthy subjects. Two hundred subjectswithanage range of 11years to70years (meanage of 33.30±12.74years)were usedfor this study. All the subjects had clear ocularmedia, normal appearance of the fundus, and visual acuityof 6/6 or better inthe testedeye. Prior toexperimentationeachsubjectwas adaptedtothe ambient roomlightingfor about 5mins. The upperlid of the eye to be tested was held firmly while a penlight was shone into the eye for about 10 seconds, PRSTwas assessed immediately after 10 seconds by asking the subjects to read at least three letters on the V.Aline immediately above the subject's best acuity line. The testing order of subjects in different age groups was randomized. Results indicated that the PSRT distribution in the sample population was found to be positively skewed with a mean of PSRTranging from10.34seconds to 46.98 seconds for an age range of 11 years to 70 years. Clinically males had slightly higher PSRT when compared to females. There was a positive relationship between age and PSRT which was highly significant (r =0.96) with a linear regression equation of PSRT=0.785+ 0.60xage. Themean increase in PSRT across consecutive age groups investigated was 27.46%. Males demonstrated a much sharper and larger increase in PSRT across consecutive age groups when compared to the females at all ages investigated except in the presbyopic age group. This study attempts to establish age related PSRTscores among healthy Nigerians in order to provide a quick reference in comparing normal physiological PSRT values and PSRTvalues arising from impending retinal/macular lesions. Keywords: Macular photostress test, Retinal photoreceptors, Retinal pigment epithelium

Functional outcome of subthreshold versus threshold diode laser photocoagulation in diabetic macular oedema

To compare the efficacy of subthreshold diode laser photocoagulation with conventional threshold diode laser in clinically significant macular oedema (CSME) in diabetics. Prospective randomised controlled trial. Thirty eyes of 20 patients with CSME having central macular thickness (CMT) >or=250 microm on optical coherence tomography (OCT) and best corrected Snellen visual acuity (BCVA) of 20/80 or better were randomly assigned to receive subthreshold diode laser (group A) or threshold laser (group B). The clinical course of BCVA, CMT on OCT, photo stress recovery time (PSRT), contrast sensitivity (CS) using Pelli Robson chart, and central visual field (10-2 VF, Humphrey Field Analyser II) were monitored regularly for 18 weeks after intervention. Both groups showed significant (P=0.03) and comparable improvement in mean BCVA at 18 weeks visit. There were also significant and comparable reductions (P<0.01) in mean CMT at all visits compared with baseline in both groups. PSRT and CS (75+/-16 (mean+/-SD) and 0.72+/-0.3 in group A and 81+/-12 and 0.68+/-0.2 in group B pre-laser) were significantly better in group A at the final visit (66+/-17 and 1.04+/-0.3) as compared to group B (78+/-11 and 0.73+/-0.3). One patient in group B showed a paracentral scotoma on 10-2 VF after the laser, which persisted till the end of follow-up. Subthreshold diode laser photocoagulation is as effective as conventional threshold laser in reducing or eliminating diabetic macular oedema (on OCT) and in improving BCVA. Recovery of macular function as assessed by CS and PSRT maybe better with subthreshold laser.

The relationship between macular pigment and visual performance

This study was designed to assess whether macular pigment optical density (MPOD) is associated with visual performance. One hundred and forty-two young healthy subjects were recruited. Macular pigment optical density and visual performance were assessed by psychophysical tests including best corrected visual acuity (BCVA), mesopic and photopic contrast sensitivity, glare sensitivity, photostress recovery time (PRT). Measures of central visual function, including BCVA and contrast sensitivity, were positively associated with MPOD ( p < 0.05, for all). Photostress recovery and glare sensitivity were unrelated to MPOD ( p > 0.05). A longitudinal, placebo-controlled and randomized supplementation trial will be required to ascertain whether augmentation of MPOD can influence visual performance.

Contralateral comparison of blue-filtering and non-blue-filtering intraocular lenses: glare disability, heterochromatic contrast, and photostress recovery

Purpose:To compare visual performance in eyes with intraocular lenses (IOLs) that filter short-wave blue light versus contralateral eyes with IOLs that do not filter visible blue light.Methods:In this prospective, assessor-masked study that was conducted at five clinics in the US, eligible candidates were at least 12 months postimplantation of a control IOL and a contralateral IOL that filtered blue light. Glare disability was defined as the intensity of a white-light annulus that obscured a subject’s ability to see a central target. Heterochromatic contrast thresholds were defined as the intensity of a blue-light disk that obscured a central target. Photostress recovery time was the duration required to regain sight of the target after a five-second flash of annulus light.Results:Fifty-two subjects were evaluated. Mean glare disability was significantly less (P = 0.04) in the blue-filtering IOL group (1.97 ± 0.44 log μW/cm2) than in the control group (1.88 ± 0.43 log μW/cm2). Mean heterochromatic contrast threshold was significantly higher (P = 0.0003) in the blue-filtering IOL group (0.36 ± 0.43 log μW/cm2) than in the control IOL group (0.15 ± 0.49 log μW/cm2). Geometric mean photostress recovery time was significantly faster (P = 0.02) in the blue-filtering IOL group (21 ± 3 seconds) than in the control IOL group (26 ± 3 seconds).Conclusions:Glare disability was significantly lower, heterochromatic contrast threshold was significantly better, and recovery from photostress was significantly faster in the eyes with blue-filtering IOLs than in the contralateral control eyes with IOLs that did not filter blue light.