ON SENSITIVITY TO GLARE AND ITS RELATIONSHIP WITH MACULAR PIGMENT

Current trends in discomfort glare research have suggested the influence of physiological parameters on individual glare perception. To this end, we hypothesize that a specific ocular physiology characteristic, namely the macular pigment (MP) in the retina, could have an influence on glare sensitivity, encouraged by recent findings from the literature that have shown that high MP levels were indicative of better visual performance. This study investigates whether a person’s sensitivity to glare could be somehow correlated to their macular pigment optical density (MPOD). We measured MPOD in 56 participants and compared it with their discomfort glare thresholds, which were determined psychophysically by exposing the participants to a series of lighting conditions varying in intensity. We found that the influence of MPOD on glare sensitivity is borderline significant with small effect size but does not follow intuition. Additional data will be required to validate and refine these initial findings.

Clinical Effects of Dietary Supplementation of Lutein with High Bio-Accessibility on Macular Pigment Optical Density and Contrast Sensitivity: A Randomized Double-Blind Placebo-Controlled Parallel-Group Comparison Trial

Improvements in macular pigment optical density (MPOD) and contrast sensitivity after administration of 12 mg lutein alone and the timing at which efficacy is observed remain unknown. Therefore, lutein (12 mg), a crystalline formulation, was used in this study, considering its bioaccessibility. This study aimed to determine the effects of lutein administration for 16 weeks on MPOD, contrast sensitivity, and glare sensitivity, and changes in serum lutein levels were determined. The study subjects comprised 59 healthy male and female adults aged 20–69 years. The study diet included a placebo (placebo group) or a diet supplemented with 12 mg of lutein (lutein group). Each study diet was continuously administered for 16 weeks. At weeks 8 and 16, MPOD, contrast sensitivity, glare sensitivity, and serum lutein levels were evaluated. Compared with the placebo group, the lutein group showed significantly improved MPOD, contrast sensitivity, and glare sensitivity at week 16 and significantly increased serum lutein levels at weeks 8 and 16. Continuous administration of lutein for 16 weeks, considering its bioaccessibility, increased MPOD; it made the outlines of visible objects clearer and was effective in inhibiting decreases in visual function caused by glare from light.

Functional outcomes after combined iris and intraocular lens implantation in various iris and lens defects

Background To assess the functional outcomes after combined iris and intraocular lens (IOL) repair in aniridia patients. Methods Retrospective observational study in 59 aniridic and aphakic eyes for ArtificialIris (AI) and IOL reconstruction. The iris prostheses were placed together with the IOL in the capsular bag using an injection system or were fixed by transscleral suturing of the IOL and AI. The primary outcomes measured were visual acuity, contrast and glare sensitivity (Pelli-Robson chart for photopic and dark adaptometer for mesopic conditions), intraocular pressure, endothelial cell density (ECD) and patient impairment. Results Blunt trauma (37 eyes) and penetrating injuries (16 eyes) were observed more frequently than congenital aniridia (1 eye), iatrogenic causes (1 eye), aniridic state after severe iritis (2 eyes) or iris tumor (2 eyes). Monocular CDVA improved significantly (p < 0.0001) from median 0.7 logMAR (0.0–1.98) to 0.3 logMAR (− 0.08–2.0). Median pupillary area could significantly (p < 0.0001) be reduced by 79.3% from 51.27 mm2 (17.91 to 98.23) to 8.81 mm2 (4.16 to 8.84). Median ECD decreased from 2646.0 mm2 to 2497.5 mm2 (p = 0.007). Contrast and glare sensitivity improved significantly (p = 0.008) in photopic light conditions from 0.9 (0.0–1.95) to 1.35 (0.0–1.8). Patients reported to be highly satisfied with the functional improvement. Conclusion The flexible ArtificialIris seems to be a safe and effective iris prosthesis in combination with an IOL having functionally and cosmetically exceptional reconstruction options.

Detection of the stroboscopic effect by young adults varying in sensitivity

The advent of LED lighting has renewed concern about the possible visual, neurobiological, and performance and cognition effects of cyclic variations in lighting system luminous flux (temporal light modulation). The stroboscopic visibility measure (SVM) characterises the temporal light modulation signal to predict the visibility of the stroboscopic effect, one of the visual perception effects of temporal light modulation. A SVM of 1 means that the average person would detect the phenomenon 50% of the time. There is little published data describing the population sensitivity to the stroboscopic effect in relation to the SVM, and none focusing on people subject to visual stress. This experiment, conducted in parallel in Canada and France, examined stroboscopic detection for horizontal and vertical moving targets when viewed under commercially available lamps varying in SVM conditions (SVM: ∼0; ∼0.4; ∼0.9; ∼1.4; ∼3.0). As expected, stroboscopic detection scores increased with increasing SVM. For the horizontal task, average scores were lower than the expected 4/8 at ∼0.90, but increased non-linearly with higher SVMs. Stroboscopic detection scores did not differ between people low and high in pattern glare sensitivity, but people in the high-pattern glare sensitivity group reported greater annoyance in the SVM ∼1.4 and ∼3.0 conditions.

Supplementation with three macular carotenoids in patients with early stage age-related macular degeneration

Introduction. Macula lutea is the central part of the retina and it houses carotenoid macular pigments - lutein, zeaxanthin, and meso-zeaxanthin. It is considered that carotenoids can prevent or slow down the progression of the early age-related macular degeneration in some patients. Therefore, the aim of this study was to examine the effects of supplementation with all three macular pigments on vision quality in patients with early agerelated macular degeneration. Material and Methods. This prospective study included 15 patients (25 eyes in total) with early age-related macular degeneration. All visual tests - visual acuity, glare sensation and contrast sensitivity, were performed at baseline and after 6 months of continuous supplementation with 10 mg lutein, 2 mg zeaxanthin, and 10 mg mesozeaxanthin. Results. The results showed that glare sensitivity improved in 20% of cases. Most of the examined eyes (76%) presented without visual acuity deterioration. Similar results were obtained for the contrast sensitivity test, where in 80% of cases vision quality remained stable or improved. There were no statistically significant differences between average values of examined parameters at baseline and after 6 months of supplementation. Conclusion. In most of the examined eyes (over 75%) visual quality remained stable or improvement of measured parameters was observed. This type of supplementation may improve visual performance or its preservation in patients with early age-related macular degeneration.

Vitrum Vision Forte therapy effect in patients with accommodative asthenopia

The article presents the results of observational study of Vitrum Vision Forte efficacy in patients with accommodative asthenopia. The changes in asthenopic complaints, Mesotest and computer accomodography data were measured. A decrease in asthenopic complaints’ incidence and severity, a statistically significant increase in mesopic vision and glare sensitivity, a statistically significant reduction in ciliary muscle microfluctuations and accommodative response stability increase were observed.