Filtering Intraocular Lenses Research Articles

Effect of Blue Light Filter Intraocular Lens (IOL) on Colour Vision.

Purpose The objective of this study is to knowthe effect of blue light filter (BF) intraocular lenses (IOL) on colour vision of Sudanese patiens as BF IOLs are relatively new in Sudan and its effect on Sudanese patients is not yet studied. Methods This was a descriptive cross-sectional observational study. Data collection was done through interview andpretested structured questionnaire containing three sections: (i) personal data, (ii) past medical and ocular surgical history, and (iii) visual acuity (VA), the anterior and posterior segment exam result, and the D15photopic color vision test result. Results In this study, 206 eyes of 103 patients were enrolled. Of them, 57 (55.3%) were females and 46 (44.7 %) were males. The mean age of the participants was 58.38 years±11.488 (SD). Furthermore, 81 patients (78.64%) achieved normal D15 color vision test results, while 22 patients (21.4%) had abnormal results. There was a significant effect (P=.00) on photopic color vision perception. Finally, the gender-wise performance showed an insignificant difference (P=.933)with 78.3% of the males having normal D15 color vision test and the females having slightly better results with 78.9 %. Conclusions The results suggested that implantation of BF IOLs has a significanteffect on photopic color vision perception.

Filtering blue light mitigates the deleterious effects induced by the oxidative stress in human retinal pigment epithelial cells

Age-related macular degeneration (AMD) is a major cause of blindness in elderly. It is characterized by the loss of central vision due to damaged retinal pigment epithelial (RPE) cells and photoreceptors. Blue Light (BL) exposure was proposed as a risk factor for AMD progression. We undertook this study to determine the effects of BL on the behaviour of RPE cells and their potential mitigation by BL-filtering intraocular lenses (IOL). Human RPE cells were exposed or not to BL, with the absence or presence of either a clear ultraviolet (UV)-filtering IOL (CIOL), or a yellow UV- and BL-filtering IOL (YIOL). Cells were analyzed for their oxidative stress by measuring the levels of reactive oxygen species (ROS), and their viability. BL exposure significantly increased the levels of both total cellular and mitochondrial ROS. While this increase was not affected by placing the CIOL in the BL beam, YIOL decreased the levels of both ROS reservoirs. Increased ROS production was accompanied by increased cell death which was similarly decreased when cells were protected with the YIOL. Pre-treatment of cells with N-acetylcycteine (NAC) abolished the increased cell death, suggesting that the effects of BL on cell viability were mainly due to increased levels of ROS. BL is deleterious to RPE cells due to increased oxidative stress and cell death. These effects were mitigated by filtering these radiations. The use of BL-filtering devices may represent a strategy to reduce these effects on RPE cells and delay the onset of AMD.

Protector Role of Intraocular Lenses under Artificial Light Conditions

Introduction: The aim of this work was to analyze, in an in vitro model, the possible protective effects of ultraviolet- (UV-) or UV/blue-filtering intraocular lens (IOL) under light-emitting diode (LED) lighting conditions. Methods: Ten models of IOLs were evaluated. Light transmission spectrum was recorded from 300 to 800 nm, in steps of 1 nm. Photodamage in vitro model was induced in ARPE-19 cells by blue LED light (465–475 nm). Changes in cell viability and oxidative stress variables were studied to assess the protective effect of IOLs. Results: UV/blue-filtering IOLs models block blue light spectrum in different proportion and UV-filtering IOLs blocking wavelength below 400 nm. However, in vitro study under blue LED light exposure does not show protective effects related with mitochondrial dysfunction and oxidative stress of UV/blue-filtering IOLs. Conclusions: The current in vitro study suggests that UV/blue filtering IOLs are not useful in terms of photoprotection in artificial light conditions. The results obtained indicate that it is needed to give attention to other IOL parameters besides the type of filter, as it seems they could have influence on the protective role.

Cataract type and pupillary response to blue and white light stimuli

We evaluated the pupil reaction to blue and white light stimulation in 70 eyes with cataract and in 38 eyes with a selective blue-light filtering intra-ocular lens. The diameter of the pupil before stimulation was set as baseline (BPD) and, after a stimulus duration of 1 s, the post-illumination pupillary response (PIPR) was measured using an electronic pupillometer. The BPD showed no significant difference among three grades of nuclear sclerosis (NS). In contrast, the PIPRs differed significantly among the NS grades eyes including with and without subcapsular cataract (SC) and IOL eyes for white light (p < 0.05, Kruskal–Wallis test), but not for blue light. Subcapsular opacity did not affect the BPD or PIPR in all cataract grades for either light stimulus. The tendency of larger PIPR in the pseudophakic eyes than the cataract eyes for both lights, however significant difference was found only for white light (p < 0.05 for white light, p > 0.05 for blue light). Our study demonstrates retention of the PIPR for blue light, but not for white light in cataract eyes. We also confirmed that the pupillary response in pseudohakic eyes with a selective blue light-filtering intra ocular lens was greater than that in cataractous eyes for white light.

Psychophysical Measurements of Luminance Contrast Sensitivity and Color Discrimination with Transparent and Blue-Light Filter Intraocular Lenses.

IntroductionThe purpose of this study was to measure luminance contrast sensitivity and color vision thresholdfs in normal subjects using a blue light filter lens and transparent intraocular lens material.MethodsMonocular luminance grating contrast sensitivity was measured with Psycho for Windows (version 2.36; Cambridge Research Systems) at 3.0, 6.0, 12.0, 20.0, and 30.0 cycles per degree of visual angle (cpd) in 15 normal subjects (eight female), with a mean age of 21.6 years (SD = 3.8 years). Chromatic discrimination was assessed with the Cambridge colour test (CCT) along the protan, deutan, and tritan color confusion axes. Both tests were performed in a darkened room under two situations: with a transparent lens and with blue light filter lens. Subjective impressions were taken by subjects regarding their visual experience under both conditions.ResultsNo difference was found between the luminance contrast sensitivity measured with transparent and blue light filter. However, 13/15 (87%) of the subjects reported more comfortable vision with the blue filter. In the color vision test, tritan thresholds were significantly higher for the blue filter compared with the transparent filter (p = 0.003). For protan and deutan thresholds no differences were found.ConclusionBlue-yellow color vision is impaired with the blue light filter, and no impairment occurs with the transparent filter. No significant differences in thresholds were found in the luminance contrast sensitivity comparing the blue light and transparent filters. The impact of short wavelength light filtering on intrinsically photosensitive retinal ganglion cells is also discussed.

The effect of lens aging and cataract surgery on circadian rhythm.

Many organisms have evolved an approximately 24-hour circadian rhythm that allows them to achieve internal physiological homeostasis with external environment. Suprachiasmatic nucleus (SCN) is the central pacemaker of circadian rhythm, and its activity is entrained to the external light-dark cycle. The SCN controls circadian rhythm through regulating the synthesis of melatonin by pineal gland via a multisynaptic pathway. Light, especially short-wavelength blue light, is the most potent environmental time cue in circadian photoentrainment. Recently, the discovery of a novel type of retinal photoreceptors, intrinsically photosensitive retinal ganglion cells, sheds light on the mechanism of circadian photoentrainment and raises concerns about the effect of ocular diseases on circadian system. With age, light transmittance is significantly decreased due to the aging of crystalline lens, thus possibly resulting in progressive loss of circadian photoreception. In the current review, we summarize the circadian physiology, highlight the important role of light in circadian rhythm regulation, discuss about the correlation between age-related cataract and sleep disorders, and compare the effect of blue light- filtering intraocular lenses (IOLs) and ultraviolet only filtering IOLs on circadian rhythm.

Effect of the blue filter intraocular lens on the progression of geographic atrophy.

To clinically evaluate the effect of blue light-filtering intraocular lenses (IOLs) on disease progression in patients with geographic atrophy (GA). Clinical data from 66 eyes of 40 patients were investigated, 27 with a blue filter and 39 with a non-blue filter IOL. Spectral-domain optical coherence tomography technology and the advanced retinal pigment epithelium analysis software tool were used to measure lesion size and monitor its progression over 1 year. The mean and median baseline area of GA for the total sample was 5.55 ± 4.72 mm2 and 4.40 mm2, respectively. There was a statistically significant difference of the mean (p = 0.0002) and median (p&lt;0.0001) GA progression in 1 year between the blue filter and non-blue filter IOL group (0.72 ± 0.39 SD mm2 mean and 0.70 mm2 median compared to 1.48 ± 0.88 SD mm2 and 1.30 mm2, respectively). The clinical data strongly support a photoprotective role of blue light-filtering IOLs on the progression of the atrophic form of dry age-related macular degeneration after cataract surgery.

The yellow intraocular lens and the natural ageing lens

The purpose of this study is to review and evaluate the advantages and disadvantages of blue light (400-480 nm) filtering intraocular lenses (IOLs) when compared with the ultraviolet (UV)-blocking IOLs. Theories that blue light could be related to the pathogenesis of age-related macular degeneration (AMD) have led to the use of yellow tinted IOLs in cataract surgery to filter short wavelength light. In spite of the potential benefits, some concerns have been raised. The potential advantages of the blue light filtering IOLs are that they could better mimic the conditions of phakia and therefore be more protective for the retina in decreasing the incidence of AMD. However, the potential disadvantages are that blue light filtering could negatively affect scotopic vision and circadian rhythms in older patients. These advantages and disadvantages of blue light filtering IOLs have not been proven clinically and thus many questions remain. Studies have shown that each type of IOL may have its own benefits and the type of IOL should be picked on the basis of patients' specific situations. In cataract surgery, considerations such as preexisting AMD, night vision problems or sleep problems may be considered with the choice of IOL.

Retinal straylight and the yellow Bag in the Lens IOL

AbstractPurpose To evaluate the influence of blue‐blocking Bag in the Lens (BIL) intraocular lens (IOL) on retinal straylight.Methods Twenty‐one patients scheduled for bilateral senile cataract surgery with a BIL intraocular implant (Morcher GmbH, Germany) randomly received implantation of either a UV light‐filtering and blue‐light filtering IOL (Morcher 89A yellow BIL) or a UV‐light filtering lOL (Morcher 89A, clear BIL) in both eyes. Only the left eyes were included in this study. Best corrected visual acuity and retinal straylight level were evaluated 3 months postoperatively with decimal charts at 4m and with C‐Quant (Oculus Optigeräte, Wetzlar, Germany) respectively.Results There were 11 eyes in the yellow BIL group and 10 eyes in the clear BIL group. Preoperative measurements (K1, K2, anterior chamber depth, axial length, IOL power) showed no significant differences between the yellow and the clear BIL group. No significant difference in visual acuity was found between both groups (p = 0.512). Mean retinal straylight did not differ significantly (p = 0.809) between yellow BIL (1.24 ± 0.26) and clear BIL (1.19 ± 0.21), even after correction for age and axial length with the pseudophakic model (p =0.557).Conclusion The UV and blue‐blocking bag‐in‐the‐lens had no influence on visual acuity and retinal straylight measured 3 months postoperatively, in comparison with a UV filtering bag‐in‐the‐lens.

Blue-light Filtering Intraocular Lenses

Blue-light filtering intraocular lenses are purported to reduce the incidence of potentially damaging UV and blue light on the retina. This article reviews their background, the proposed benefits on long-term eye health and the possible disadvantages on circadian rhythm, scotopic vision and colour vision.

Spektrale Durchlässigkeit bei Blaufilter-Intraokularlinsen

There is uncertainty in ophthalmology concerning the quality and spectral transmission of light of so-called blue filter intraocular lenses (IOL). Clinical users have noticed that such IOL's appear to have different color intensities. The discussion on medical changes by means of such IOL's is dependent on the real light transmission of these IOL's. To add some objective data we compared these IOL's by systematic transmission measurements and observed technical differences of diffraction and geometry as well as transmission differences. The result gives objective indications that differences between blue filter IOL's from different manufacturers are important and are detailed in this paper.

Influence of Blue Light-filtering Intraocular Lenses on Retinal Nerve Fiber Layer Measurements by Spectral-domain Optical Coherence Tomography

Purpose: The purpose of this study was to assess the influence of blue light-filtering intraocular lenses (IOL) on peripapillary retinal nerve fiber layer (RNFL) thickness measurements by spectral-domain (SD) optical coherence tomography (OCT).Methods: This prospective study included 50 eyes of 50 patients. Patients were randomly assigned to receive either a blue light-filtering IOL (acrysof IQ (SN60WF) [Alcon]) or a clear IOL (Tecnis (Z9003) [AMO]). The peripapillary RNFL thickness was measured using a Cirrus SD OCT before and 8 weeks after cataract surgery. Perioperative differences in RNFL thickness measurements and signal strengths (SS) were evaluated and compared in both IOL groups.Results: Thirty-nine eyes of 39 patients were included in the final analysis. There was a significant increase in average RNFL thickness and SS after cataract surgery in both IOL groups. No significant difference in perioperative changes of RNFL measurements was noted between yellow and clear IOL groups. In the multivariable analysis, the factor affecting perioperative differences of RNFL measurements was not IOL type but SS.Conclusions: Our data suggests that blue-light filtering IOL does not influence RNFL thickness measurements by Cirrus SD-OCT.

Influence of Blue-Light-Filtering Intraocular Lenses on Color Perception and Contrast Acuity

To compare contrast acuity at different illumination levels and color vision and the subjective impression in patients after bilateral cataract surgery with a mixed implantation of a blue-light-filtering and an ultraviolet (UV)-filtering intraocular lens (IOL). Randomized, controlled, double-masked, and bilateral study with intraindividual comparison. This study included 48 eyes of 24 consecutive patients with age-related cataract. Each patient had standardized small incision cataract surgery with IOL implantation into the capsular bag. Patients were randomly assigned to receive a blue-light-filtering Hoya AF-1 (UY) YA-60BB IOL in one eye and a UV-filtering Hoya AF-1 (UV) VA-60BB IOL (Hoya Medical Europe, Frankfurt/Main, Germany) in the contralateral eye. Contrast acuity was measured at illumination levels of 500, 5, and 0.5 lux and contrast levels of 100%, 50%, 25%, 12.5%, and 6.25%. Color vision was assessed using the Lanthony desaturated D-15 test, the Lanthony new color test (Munsell chroma 2 and 4), and an anomaloscope. Blue/yellow foveal threshold was tested applying short-wave automated perimetry. The subjective visual impression of patients was evaluated using a questionnaire. Contrast acuity, color vision, and foveal threshold. The blue-light-filtering IOLs had worse contrast acuity (P = 0.0004) and foveal threshold (P = 0.008) compared with the UV-filtering IOLs. Color vision tests and high-contrast visual acuity did not show any statistically significant differences between IOLs (P>0.05). On questioning, 3 of 24 patients noticed a difference between the implanted IOLs concerning visual impression. This study shows that blue-light-filtering IOLs negatively affect contrast acuity and blue/yellow foveal threshold when compared with UV-filtering IOLs. Although the differences were small, the results suggest bilateral implantation of the same IOL type and avoidance of a mixed implantation of a blue-light-filtering IOL in one and a non-blue-light-filtering IOL in the contralateral eye in patients with high demands in color vision. The author(s) have no proprietary or commercial interest in any materials discussed in this article.

Blue Light–Filter Intraocular Lenses in Vitrectomy Combined with Cataract Surgery: Results of a Randomized Controlled Clinical Trial

To evaluate the effect of the blue light-filter intraocular lenses (IOLs) in vitrectomy combined with cataract surgery, focusing on the surgeon's ability to perform specific vitreoretinal procedures and on the patients' outcome. Randomized clinical trial. Sixty patients, recruited from our outpatient department, were assigned randomly to receive an ultraviolet-filter IOL (clear IOL group) or a blue light-filter IOL (yellow IOL group) combined with a vitreoretinal procedure. Main outcome measures were intraoperative conditions for the surgeon and the functional outcome. Second outcome measures were complication rates and vitreoretinal diagnoses. The questionnaire responses showed that the blue light-filter IOLs did not represent an impediment to vitreoretinal surgery (P>.05). No intraoperative complications were encountered in either group. Patients in both IOL groups showed comparable functional results with respect to visual acuity, contrast sensitivity, color vision, and glare effect (P>.05). The functional outcome was influenced significantly by the vitreoretinal diagnosis (P<.01). With the possible advantage of macular protection and no intraoperative or functional disadvantage, the routine use of the blue light-filter IOL in combined surgery can be recommended.

Ultraviolet radiation and age-related macular degeneration: the protective benefit of blue-light-blocking intraocular lenses. A literature review

Aim: To evaluate the association between ocular sunlight exposure and the risk of age-related macular degeneration (ARMD), and to explore the retinal protection offered by blue-light filters in ultraviolet intraocular lenses (IOLs). Methods: A literature search was undertaken using the Pub Med and Web of Knowledge databases. Non- English-language studies were not included. The review considers the effect of ultraviolet light on the eye with particular attention to retinal effects and ARMD. The blue-light hazard is considered, includ­ing the concept of blue-light filters in IOLs. Results: The majority of papers did not find any statistical significance between sunlight exposure and ARMD. However, there were some statistically significant relationships between sunlight and early ARMD. Blue light has caused photochemical retinal damage in animal studies. Therefore, the presence of blue-light filters in IOLs may be indicated. Although theoretical predictions suggest a decrease in scotopic sensitivity with blue-light filter IOLs, clinical studies did not replicate these findings. Conclusion: A causal association between ocular exposure to sunlight and the development of ARMD cannot be established from current literature. More epidemiological research is required to ascertain any strong association between sunlight exposure and ARMD, and to explore the effectiveness of ultraviolet and violet radiation-filtering IOLs.

Visuelle Funktion mit Blaulichtfilter-IOL

Recently, intraocular lenses (IOLs) with a blue light filter have been introduced to protect the retina from age-related macular degeneration (AMD) after cataract extraction. A reduction of longitudinal chromatic aberration by filtering blue light may enhance patient's visual function. In this study we compared subjective and objective parameters of visual function following implantation of blue light filter (yellow) IOLs and IOLs of the same design without filter. 21 patients (21 eyes) underwent implantation of an IOL with a blue light filter (AF-1 UY, Hoya, Japan), 22 patients (22 eyes) received an IOL without blue light filter (AF-1 UV, Hoya, Japan). Patients were examined three months postoperatively for uncorrected and best corrected spectacle visual acuity, mesopic and photopic contrast sensitivity, colour vision and subjective quality of vision by a standard questionnaire. Eyes with blue light filter IOLs did not show any significant difference in any parameter analysed when compared to eyes without the blue light filter IOL. Subjective quality of vision was considered to be high by all patients and no significant difference was observed between the two IOL groups. The visual function of patients with blue filter IOLs is not significantly different to those without blue light filter IOLs. Since blue light filter IOLs did not show any functional disadvantage, but potentially protect the macula from AMD, blue light filter IOLs may be considered as a reasonable alternative to traditional IOLs, especially in eyes with a high risk for the development of macular degeneration.

Contrast sensitivity and higher order aberrations with aspheric and blue-light filter intraocular lenses

Zahlreiche Intraokularlinsen (IOLs), welche die visuelle Funktion durch Reduktion der spharischen oder chromatischen Aberration nach Kataraktoperationen verbessern konnten, wurden in den letzten Jahren zugelassen. In dieser Studie untersuchten wir Kontrastsehen und Aberrationen hoherer Ordnung bei Patienten mit aspharischen und gelben IOLs.

The economic impact of blue-light filtering intraocular lenses on age-related macular degeneration associated with cataract surgery: a third-party payer's perspective

ABSTRACTObjectives: Epidemiological data support an association between age-related macular degeneration (AMD) and cataract surgery that may be attributed to post-operative blue light exposure. By limiting the retina's blue light exposure, new blue-light filtering intraocular lenses (BLF IOLs) have the potential to reduce the development of AMD following cataract surgery. In the current economic healthcare environment, there is increased interest in the cost impact of new medical technologies. The objective of this analysis was to evaluate the cost impact of a BLF IOL versus a non-BLF IOL in cataract surgery.Methods: An economic model was developed to emulate three age-specific cohorts and to assess the clinical and economic outcomes over 5 years. Data from the published literature was supplemented with clinical expert opinion. Key literature inputs involved the risk of AMD after cataract surgery as well as laboratory and animal data on the effectiveness of the BLF IOL in reducing the risk of AMD. Clinical experts provided information on the management of AMD. Direct medical costs including the cost of the IOL, monitoring, and AMD prophylaxis and treatment and AMD prophylaxis and treatment were incorporated into the model. All costs were standardized to 2004 US dollars. Age-stratified sensitivity analyses were conducted.Results: In the BLF IOL group, the 5-year age-stratified incidence of AMD ranged from 0.58 to 9.23 per 100 eyes, compared with 1.69 to 24.55 per 100 eyes in the non-BLF IOL group. The incremental cost of the BLF was offset by reduced costs associated with averted AMD treatment. Estimated savings with BLF IOLs per 100 eyes were $4275, $29 997, and $111 734 in the 55 to 64 year-old, 65 to 74 year-old, and > 75-year-old cohorts, respectively; these findings remained robust throughout the sensitivity analyses.Conclusion: Limitations of this analysis include the lack of prospective clinical trial data that definitively demonstrate the efficacy of a BLF IOL in preventing AMD. Moreover, the efficacy data used to populate the model were derived from laboratory and animal studies. Thus, based on preliminary data, this study suggests that the economic benefits of implanting BLF IOLs during cataract surgery are observed in all patients over a 5‐year timeframe although cost savings are greatest in patients ≥ 75 years.

Blood-retinal barrier in pseudophakias with blue-light filtering intraocular lenses

Blood-retinal barrier in pseudophakias with blue-light filtering intraocular lenses

Erythropsial phototoxicity associated with nonultraviolet-filtering intraocular lenses

Four patients with monocular erythropsia (seeing red) caused by excessive exposure to bright light are presented. Each patient had a nonultraviolet (UV)filtering intraocular lens (IOL) in the involved eye; the fellow eye was either phakic or had a (UV)-filtering IOL. Each patient had seen a definite red hue to lights (moon, automobile headlights, etc.) only at night after prior prolonged exposure to high-intensity sunlight and only in the eye with a non-UV-filtering IOL.