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Daylight influences more than just our vision; elements such as its intensity and spectral composition can significantly impact our circadian rhythms and, consequently, our overall well-being. In this study, we present an analysis of a classroom simulated in Dialux, involving a comprehensive examination of natural daylight through a specific type of glazing, assessing their photopic characteristics and their influence on the human circadian system in individuals aged 32 and 70 years. Our findings highlight that spectral data from daylight (D75, D65, and D50) and glazing transmittance can be easily used to evaluate the melanopic equivalent daylight illuminance (mel-EDI) in addition to standard photopic illuminance, applying a f ( M P ) G l a z i n g factor calculated from the spectral characteristics of both daylight and glazing transmittance. Our results provide new insights for users to more effectively assess daylighting quality and its implications within indoor environments. [ABSTRACT FROM AUTHOR]

This study quantitatively analyzes the influence of the spectral characteristics, reflectance or transmittance, of different materials on the lighting of an interior space with natural and artificial light. For this purpose, a three-dimensional simulated classroom is used, where each of the components is assigned specific materials with an associated reflectance or transmittance. Additionally, two types of lighting are available: 6500 K daylight and light from six continuous spectrum LED luminaires. The lighting is evaluated on two planes: the work plane and the corneal plane (80 cm and 120 cm from the floor, respectively). Three versions of the same classroom were analyzed by varying the walls (white, blue, and red), each with a different neutral-colored floor. Furthermore, calculations were performed in each situation considering two different types of glazing in the windows, with 20% and 88% transmittance. The photopic and melanopic lighting analysis was carried out with the ALFA calculation program to verify the necessary requirements for adequate lighting. The results show that the white classroom is the best lit, followed by the blue and finally the red, due to the reflectance characteristics of the walls and floor although slight differences among them are found. It was found that in some cases, additional auxiliary luminaires would be required for proper lighting depending on the transmittance of the glazing. This study highlights the critical role of material selection in optimizing both photopic and melanopic lighting, with practical implications for energy efficiency and occupant well-being in educational spaces. [ABSTRACT FROM AUTHOR]

The aim of the study is to compare macular sensitivity and retinal thickness in patients with long-term type 1 diabetes mellitus (DM1) without diabetic retinopathy (DR) after 5 years of follow-up. Thirty-two eyes from 32 long-term DM1 patients without DR were included. All participants underwent a complete ophthalmological examination, including microperimetry and spectral domain optical coherence tomography (SD-OCT). The data were compared with results from 5 years prior. The mean age of the DM1 patients was 43.19 ± 10.17 years, with a mean disease duration of 29.84 ± 8.98 years and good glycemic control. In 2023, patients exhibited a significantly worse best corrected visual acuity (BCVA) compared to 2018 (p < 0.001). DM1 patients did not show statistically significant changes in macular sensitivity over the 5-year follow-up period. Macular integrity showed significant differences between the two time points (p = 0.045). Retinal thickness showed significant differences, particularly in inner retinal layers (IRL) across most of the ETDRS areas. Long-term DM1 patients without DR lesions showed worsened macular integrity and a lower BCVA in 2023. Additionally, they displayed significant alterations in retinal thicknesses, especially in the IRL, between 2018 and 2023. These findings suggest that even in the absence of visible DR, long-term DM1 patients may experience subclinical retinal changes and functional deterioration over time, highlighting the importance of regular monitoring for the early detection and management of potential complications. [ABSTRACT FROM AUTHOR]

Background: Three computerized tests were designed to evaluate visual function, alertness, and visuocognitive integration under three different lighting conditions (white, red, and blue lighting). Methods: Three computerized tests were designed and programmed using the experimental design software PsychoPy version 2023.2.2. Test 1 evaluated visual acuity (VA), Test 2 assessed contrast sensitivity, and Test 3 measured alertness. This study was conducted on 53 young subjects who performed three computerized tests after adapting to each of the three different lighting conditions. A baseline aberrometric measurement was taken before and after the tests for each lighting condition. Measurements of accuracy and reaction time were taken for each test, along with total, high-, and low-order aberration values for each situation. Results: Statistically significant differences (p ≤ 0.05) were found among the different lighting conditions across the three tests, with white lighting yielding better performance in Test 1 and Test 3. Additionally, the aberrometric analysis revealed significant differences (p ≤ 0.05), with the baseline measurement being more myopic. Conclusions: White lighting produced the best VA results and faster reaction times, whereas red lighting had poorer VA effects. These findings suggest that different lighting conditions induce changes in vision and alertness, although further research is needed to understand the underlying causes. [ABSTRACT FROM AUTHOR]

To study retinal and choriocapillaris (CC) alterations using optical coherence tomography angiography (OCTA) in long-term type 1 diabetic (DM1) patients without diabetic retinopathy (DR). Seventy-eight eyes from 78 well-controlled DM1 patients diagnosed at least 15 years prior and 130 eyes of 130 healthy subjects were included in a cross-sectional descriptive study. Six eyes were excluded from the DM1 group. OCTA with Deep Range Imaging (DRI)-Triton swept source (SS)-OCT was performed. Statistically significant differences were found in all areas of the superficial capillary plexus (SCP), with lower values in DM1 patients. Differences were noted in all quadrants of the deep capillary plexus (DCP) except for the central area. Significant changes in CC blood flow were only found in the center. The foveal avascular zone (FAZ) area and diameters in the SCP were significantly different, while the DCP FAZ area was similar in both groups. Disease duration and microalbuminuria correlated negatively with some SCP areas and positively with FAZ values. Anatomical evaluation revealed microaneurysms in both plexuses, FAZ modifications, and areas lacking blood perfusion. Long-term type 1 diabetic patients without DR display microvascular abnormalities affecting retinal and CC blood perfusion, along with anatomical changes in retinal blood vessels. [ABSTRACT FROM AUTHOR]

Accommodation mainly affects the lens, a structure of the eyeball that degrades with age. The aim of this work was to study the morphological changes of different ocular structures during accommodation, both in the anterior pole and the posterior pole, which may also be involved in the accommodation process. The study will be carried out by stimulating accommodation through lenses of -1.00, -3.00 and -5.00 D starting from the spherical equivalent (M) of each participant in different age groups, from 18 to 66 years. To obtain the M value, aberrometry was achieved, and retinal optical coherence tomography and anterior pole tomography were performed to evaluate the possible structural modifications (central and peripheral), while accommodation was progressively stimulated. It showed that as the accommodative demand increased, morphological changes were produced in retinal thickness, both in the central and peripheral retina, in all age groups. A thinning of the retina was observed in the central 3 mm, while significant progressive thickening was observed closer to the periphery (up to 6 mm from the fovea) as the required accommodative power increased. A decrease in the anterior chamber depth (ACD) and anterior chamber volume (ACV) was observed with increasing lens power. Structural changes were observed in the central and peripheral retina, as well as in the ACD and ACV, while progressively greater accommodation was stimulated, showing that these structures were modified in the accommodation process even in advanced presbyopes. [ABSTRACT FROM AUTHOR]

Background: To evaluate changes in pattern electroretinogram (pERG) and pattern visual evoked potentials (pVEP) in patients with long-lasting type 1 diabetes without diabetic retinopathy (DR). Methods: Prospective study involving 92 eyes divided into two groups. The diabetic group included 46 eyes of 23 patients with type 1 diabetes (T1DM); the control group included 23 age-matched healthy subjects. pERG and pVEP were assessed using the RETI-port/scan21 recording software (version 1021.3.0.0). Results: Mean age was 48 ± 9.77 years for the diabetic group and 51.7 ± 4.75 years for the control group. The mean duration of diabetes was 28.88 ± 8.04 years. The mean HbA1c value was 7.29 ± 0.89%. There were no differences in the age or sex distribution. Regarding the pERG, T1DM patients exhibited a significant decrease in the amplitude of the P50 and N95 waves compared to the control group (p = 0.018 and p = 0.035, respectively), with no differences in the peak time of each component. pVEP showed no significant changes in either peak time or amplitude of the different components. Conclusions: Long-term T1DM patients without DR showed changes in the amplitude of pERG waves with preserved peak times. We did not observe modifications in pVEP. pERG may serve as a subclinical marker of ganglion cell damage in long-term T1DM patients. [ABSTRACT FROM AUTHOR]

Background: We aimed to study the optical and retinal modifications that occur after adapting to different lighting conditions including photopic, mesopic, scotopic, blue light and red light conditions. Methods: Thirty young healthy subjects with a mean age of 23.57 ± 3.45 years were involved in the study (both eyes included). They underwent aberrometry and optical coherence tomography at both the central and peripheral retina with the 3 × 3 mm2 macular cube protocol before starting adaptation to the illuminations (baseline) and after remaining for 5 min under the five different lighting conditions inside a controlled lighting cabinet. Results: Significant myopization (p = 0.002) was observed under scotopic and mesopic lighting conditions, while hypermetropization occurred under the influence of blue LED light. In the central retina, a significant thickening of the inner temporal (p = 0.025) and outer inferior (p = 0.021) areas was observed in the scotopic area, and the thickening increased even more under blue and red light. The mean central thickness decreased significantly under photopic lighting conditions (p = 0.038). There was an increase in the mean volume of the central retinal area with red light and a reduction in the volume under photopic lighting (p = 0.039). In the peripheral retina, no significant thickness changes were observed after adapting to any of the lighting conditions (p > 0.05). Regarding morphological changes, a significant increase in retinal eccentricity (p = 0.045) and the shape factor (p = 0.036) was found. In addition, a significant correlation was found only between the eccentricity and volume of the central retina in scotopic conditions (r = −0.265; p = 0.041), meaning that a higher volume was associated with lower retinal eccentricity. Conclusions: When exposed to different lighting conditions, the retina changes in shape, and ocular refraction is modified to adapt to each condition, revealing the phenomenon of night myopia when transitioning from photopic to scotopic regimes. [ABSTRACT FROM AUTHOR]

The vergence facility (VF) test is important in a complete optometric examination, but there is still controversy over which prismatic power combinations to use according to the patient age, especially in children. The aim of this work is to study the VF test using three different prismatic power combinations in four age groups, with a view to determine the best prismatic power for performing the test. The VF of 122 healthy subjects was evaluated using three prismatic flippers with different powers: 8∆ base-in with 8∆ base-out (8BI/8BO∆), 3BI/12BO∆ and 5BI/15BO∆. The number of cycles per minute (cpm) was counted. The participants were divided into four age groups. The mean age of group 1 was 6.69 ± 0.65 years, that of group 2 was 9.36 ± 0.87 years, that of group 3 was 12.08 ± 0.79 years and that of group 4 was 28.67 ± 8.11 years. The mean cpm value in VF was higher for near vision than in distance vision. The lowest cpm values were observed in the youngest group (group 1) (far vision: 8BI/8BO∆: 2.32 cpm, 3BI/12BO∆: 2.68 cpm and 5BI/15BO∆: 1.59 cpm; near vision: 8/8∆: 6.59 cpm, 3BI/12BO∆: 7.77 cpm and 5BI/15BO∆: 5.27 cpm). The cpm values increased progressively with age, with group 4 achieving the highest cpm values (far vision: 8BI/8BO∆: 3.61 cpm, 3BI/12BO∆: 8.56 cpm and 5BI/15BO∆: 5.28 cpm; near vision: 8BI/8BO∆: 10.22 cpm, 3BI/12BO∆: 12.28 cpm and 5BI/15BO∆: 10.89 cpm). VF increased with age. The youngest children achieved the lowest cpm values, which progressively increased until the highest cpm values were achieved in adults. The best results were found with 3BI/12BO∆ in all groups in near and far vision. Higher cpm values were achieved in near vision than in far vision with all flippers in all groups. [ABSTRACT FROM AUTHOR]