Ophthalmic and Physiological Optics最新文献

This study was aimed at assessing the effects of a 6-week intervention within a training environment that uses special lighting conditions targeted to slow down the visual processing speed of visual and visuomotor performance in professional soccer players. Twenty-four soccer players (age = 21.8 ± 4.8 years, 50% women) from the under 18 and under 23 men's teams, and 1st Women's team of the Sunderland Association Football Club participated in this study. Participants were randomly assigned to the intervention and control groups, with the intervention group performing 2-weekly 30-min sessions of specific soccer tasks with specific lighting conditions using the Okkulo system (Okkulo™, okkulo.com), whereas the control group performed the same training under normal lighting conditions. The intervention group showed significant improvements in dynamic visual acuity (p < 0.001), recognition time (p = 0.002), sensory reaction time (p < 0.001), motor reaction time (p = 0.002) and peripheral identification accuracy (p < 0.001), whereas no significant effects were obtained for stereopsis (p = 0.05), peripheral identification speed (p = 0.17) and anticipation (p = 0.22). In conclusion, a 6-week training intervention using the Okkulo system improved several visual and visuomotor skills in professional soccer players. Future studies will assess the transfer effects of using this technology to on-field performance.

Purpose: To explore the longitudinal changes in retinal and choroidal thickness and their relation with the onset of type 1 diabetes mellitus (T1DM) in children.

Methods: Thirty-eight children with T1DM and 71 healthy controls were included in this 3-year longitudinal study. Ophthalmic and systemic examinations were conducted on each participant. Retinal and choroidal thickness were measured by optical coherence tomography. Baseline values and changes in retinal and choroidal thickness were compared with DR onset, diabetics without DR and healthy controls. Logistic regression was used to explore the association with DR development.

Results: Six children developed DR during the follow-up period (15.79%) and five of them developed microaneurysms in the parapapillary temporal quadrant. During follow-up, greater retinal thickening occurred in subjects with DR compared with diabetic participants without DR (p = 0.03) and healthy controls (p = 0.02) in the parapapillary outer temporal section. Compared with the control group, greater retinal thickening was observed in DR subjects in the averaged parapapillary outer ring (p = 0.01), the macular inner temporal section (p = 0.03) and several macular sections (all p < 0.05). Additionally, greater retinal thickening was observed in several parapapillary regions in non-DR T1DM participants compared with healthy controls (all p < 0.05). The thickness change in the outer temporal parapapillary section was independently associated with DR onset (OR = 1.33, 95% CI 1.01-1.73, p = 0.04).

Conclusion: Children with T1DM showed a significant or a trend of increasing retinal and choroidal thickness compared with normal controls over a 3-year period. The change of retinal thickness in the parapapillary outer temporal section was associated with the development of DR in children with T1DM, suggesting that it could serve as a biomarker for predicting and screening DR in these individuals.

Purpose: Cerebral visual impairment (CVI) is a brain-based condition which can be exacerbated by clutter. This study aimed to explore the relation between clutter and visual fatigue in children with CVI and evaluate the effectiveness of clutter algorithm metrics in assessing visual clutter in photographs of children's play areas and the relation to visual fatigue.

Methods: Visual clutter was measured using algorithmic metrics, subjective observations by a clinical researcher (who also observed visual fatigue) and a Qualtrics survey.

Results: Seventy-two children (mean performance age = 7 years 4 months) were included. Visual fatigue was present in over 90% of children. Results revealed a relation between clutter and visual fatigue observations (r_s = 0.29; p = 0.01) and between visual clutter observations from researchers and Qualtrics participants (r_s = 0.32; p = 0.02). Certain metrics were correlated with visual clutter observations (r_s ranging from -0.30 to 0.51, p-values ranging from <0.001 to 0.03), but not with visual fatigue.

Conclusions: Children with CVI presented with visual fatigue, particularly in cluttered environments. Therefore, parents, caregivers, teachers and clinicians should be attentive to visual fatigue signs, as early recognition and intervention can help address the child's needs more effectively. Algorithms that effectively quantify visual clutter are valuable tools that can be integrated to enhance the assessment of clutter and its relation with visual fatigue to advance CVI research methodology. However, a clinician is required to assess visual fatigue and to obtain detailed information on environmental clutter, which algorithms alone may not fully capture. Finally, we recognise that visual fatigue and the impact of clutter should be integrated into psychoeducation and the comprehensive assessment of individuals with CVI.

The Maddox rod is a staple in the assessment of strabismus. However, its optics mechanism is puzzling. How is it that an orthogonal line focus is formed? Surprisingly, few texts offer an explanation and those that do either provide insufficient detail, contain misleading information or are difficult to follow. There is a prevalent misconception that multiple cylinders are required for the orthogonal line focus to appear. However, this is untrue; Maddox himself only used a single cylinder when he first described the phenomenon. Herein, we review the optics explanations provided in a sample of texts and offer an accurate explanation using the biplanar principle of astigmatic refraction.

Purpose: To compare the parameters and indices of a novel swept-source optical coherence tomography device (SS-OCT, ANTERION) with those of a rotating Scheimpflug camera (RSC)-based tomograph (Pentacam) in normal and keratoconic (KC) eyes.

Methods: This prospective, monocentric, cross-sectional study included individuals with unoperated normal and KC eyes, selecting one eye per subject. Ectasia-specific parameters analysed with the SS-OCT were difference in mean keratometry (K_mean) in the inferior and superior meridians, maximum keratometry value (K_max), elevation of the posterior surface at the thinnest point, screening corneal objective risk of ectasia (SCORE) and thinnest point thickness. With the RSC, parameters determined were Belin/Ambrosio total deviation value (BAD-D), index of height decentration and index of vertical asymmetry. KC classification with the SS-OCT was based on the anterior and posterior radii of curvature and thinnest point thickness according to the ABCD classification of the RSC system.

Results: This study included 117 individuals with healthy eyes and 335 eyes with KC. The indices with the highest diagnostic discriminatory ability between the two cohorts were SCORE, difference of K_mean in the inferior and superior meridians and posterior elevation of the thinnest point (SS-OCT), as well as the index of height decentration, index of vertical asymmetry and BAD-D (RSC). The classifications using SS-OCT defined mild-stage KC as K_max, posterior elevation of the thinnest point and thinnest point thickness as ≤50.9 D, ≤30 and ≥472 μm, respectively. Moderate stage values were 51-55.9 D, 31-69 and 471-438 μm, respectively, while respective advanced stage were ≥56 D, ≥70 and ≤437 μm.

Conclusion: The diagnostic capabilities for both devices were found to be comparable. KC classification using SS-OCT can be independently based on the anterior surface, posterior surface and corneal thickness.

Purpose: To assess longitudinal changes in optical quality across the periphery (horizontal meridian, 60°) in young children who are at high (HR) or low risk (LR) of developing myopia, as well as a small subgroup of children who developed myopia over a 3-year time frame.

Methods: Aberrations were measured every 6 months in 92 children with functional emmetropia at baseline. Children were classified into HR or LR based on baseline refractive error and parental myopia. Zernike polynomials were calculated for 4 mm pupils, accounting for the elliptical shape of the pupil in the periphery. Various metrics were computed, including Strehl Ratios with only high-order aberrations (HO-SR). Primary spherical aberration (SA), horizontal coma and defocus were also analysed given their relevance in emmetropisation. The areas under the image quality metrics for various regions of interest were computed.

Results: HO-SR were higher in children at HR and children with myopia, even when SA was removed from the Strehl Ratio (SR) calculation. SA was less positive in children at HR and children with myopia. Defocus was more negative in children at HR and children with myopia at all eccentricities and was even more negative when computed relative to the fovea, an effect that increased in the mid periphery. Relative peripheral defocus also became more negative over time in children at HR and children with myopia at the mid temporal retina. The other aberrations showed no significant changes in time overall.

Conclusions: This longitudinal study showed differences in HO-SR, SA and defocus in the central and near-peripheral retina (±20°) of young children at HR before they develop myopia compared with children at LR for myopia. The results may indicate these eccentricities are significant in providing signals for emmetropisation. The small changes noted over time may indicate that the differences are a cause of myopia development.

Purpose: The aim of this study was to investigate changes in the light-adapted (LA) electroretinogram (ERG) associated with paediatric amblyopia.

Method: A total of 220 eyes from 81 postoperative paediatric cataract patients and 29 healthy children were enrolled in four groups, namely controls, unilaterally amblyopic eyes, non-amblyopic fellow eyes and bilaterally affected eyes. Differences in LA ERG variables (peak time and amplitude of a- and b-waves and photopic negative response [PhNR]) were compared across groups, as well as their associations with visual acuity and changes in axial length.

Results: The peak time of both the a-wave (p < 0.001) and b-wave (p < 0.001), as well as the amplitude of the b-wave (p < 0.001) and the PhNR (p = 0.04) differed significantly across groups. Compared to controls, affected eyes in both unilateral and bilateral groups showed significantly lower b-wave amplitude and longer a- and b-wave peak times (p < 0.008, Bonferroni-corrected). Additionally, fellow eyes in the unilateral group exhibited significantly longer b-wave peak times (p = 0.008). For all eyes, poorer visual acuity was associated with a longer peak time for both the a- (p = 0.006) and b-waves (p = 0.003), as well as lower amplitudes of the b-wave (p = 0.006) and PhNR (p = 0.02).

Conclusions: Changes in LA ERG components suggest alteration of retinal physiology in deprivation amblyopia. Thus, the LA ERG may provide additional information to help understand the mechanisms underlying deprivation amblyopia.

Purpose: Myopia, a leading cause of correctable visual impairment, is projected to affect nearly 50% of the global population by 2050, posing a significant public health challenge. Understanding its prevalence and associated factors, particularly in children, is crucial for devising prevention and intervention strategies. This study aims to determine the proportion of myopia in school-aged children in Portugal and to examine the correlation between myopia occurrence and various environmental and genetic factors.

Methods: A cross-sectional epidemiological study was conducted on children aged from 5 to 17 years from nine schools in Lisbon, Portugal, between September 2020 and May 2021. It included optometric assessments to evaluate refractive status and binocular vision, as well as questionnaires about their lifestyles and parental myopia.

Results: Out of 1992 participants enrolled, 12.7% of the children were found to be myopic. The proportion of myopia increased with age and was higher in girls. A significant association was observed between myopia and parental history, with the likelihood being higher if one or both parents were myopic. Engaging in outdoor activities was associated with a lower likelihood of myopia.

Conclusions: The study found that 12.7% of the children in the study sample, aged 5-17 years, were myopic, indicating a significant association with familial history and limited outdoor activities. These insights highlight the need for targeted myopia screening and prevention strategies in the paediatric population.