Clinical Optometry最新文献

Introduction: Spectacle lens design for myopia control incorporates either lenslet or diffusion technology to slow down the eye growth, which may impact the binocular vision functions of a myopic child. This study aimed to investigate the changes in accommodation and binocular functions in myopic children over 12 months wear of myopia control spectacle lenses.

Methods: 21 myopic children aged 7-12 years were prescribed with Defocus Incorporated Multiple Segments (DIMS) lenses and assessed at baseline, 1, 3, 6, 9, and 12 months. The parameters measured were refractive error, axial length (AL), visual acuity (VA), accommodative lag (LA), amplitude of accommodation (AA), negative/positive relative accommodation (NRA/PRA), stereoacuity, near point of convergence (NPC), phoria, negative/positive fusional vergence (NFV/PFV), and accommodation convergence per accommodation ratio (AC/A).

Results: Mean spherical equivalent (SE) and AL increase from -2.90 ± 1.15 D and 24.51 ± 0.99 mm to -3.19 ± 1.25 D and 24.60 ± 0.97 mm at 12 months respectively. Visual acuity (VA) significantly improved (p < 0.001) in both high-contrast and low-contrast conditions at distance and near. Regarding accommodation and binocular functions, significant improvements were observed in lag of accommodation (LA), stereoacuity and gradient AC/A ratio (p < 0.001). The NPC reduced slightly but was still within normal limits. Distance and near phoria shifted toward esophoria with changes less than 1 PD. Additionally, distance NFV and near PFV recovery points increased significantly.

Conclusion: This study demonstrated insignificant changes in accommodation and binocular functions in myopic children after 12 months of wearing DIMS lenses. However, the absence of a control group limits causal interpretation, as observed changes may be influenced by natural development, repeated testing, or regression to the mean. Further research with controlled designs is warranted to clarify these effects.

This narrative review explores the relationship between African facial anthropometry and spectacle frame design. Despite the global eyewear market's growth, a significant gap exists in designs accommodating African facial features. Through a comprehensive literature analysis, this review examines key anthropometric measurements relevant to eyewear fit across diverse African populations, current challenges in spectacle frame design, and emerging solutions. Findings reveal persistent underrepresentation of African facial measurements in global design standards, leading to poor fit, discomfort, and reduced compliance. The review identifies opportunities for innovative frame designs, material selection, and manufacturing approaches that could better serve African populations. Recommendations include increased anthropometric research across different African ethnicities, integration of digital technologies, and development of region-specific design parameters. This review contributes to the growing body of knowledge advocating for more inclusive and culturally appropriate eyewear solutions.

Purpose: More frequent replacement of contact lenses may be beneficial for ocular health, but satisfied wearers often have prescriptions renewed in the same lens. This study sought to evaluate the wear experience of a newly released 1-week replacement lens among currently satisfied wearers of a 2-week replacement lens.

Methods: This open-label, non-comparative study of single vision lenses recruited satisfied wearers of senofilcon A and refit them in serafilcon A. Participants wore the study lenses for two weeks. Assessments included visual acuity and surveys regarding wear experience: the Contact Lens Dry Eye Questionnaire-8 (CLDEQ-8); visual analog scale (VAS) ratings of vision quality and comfort; VAS ratings of vision and comfort during a variety of activities; and ratings of convenience, satisfaction and ease of use on a 0 to 10 Likert scale.

Results: Sixty-two participants completed the study. Median (interquartile range) distance LogMAR acuity with the study lenses was -0.15 (0.12) OD, -0.16 (0.10) OS, and -0.22 (0.08) OU. The median (IQR) CLDEQ-8 score was 10 (10). Median (IQR) VAS responses were 91 (22) for overall quality of vision and 83 (30), for overall comfort. Median VAS responses regarding specific activities ranged from 87 to 91 for vision and 81 to 90 for comfort. Median (IQR) ratings were 8 (2) for convenience, 10 (1) for ease of use, and 9 (2) for satisfaction.

Conclusion: In this study, satisfied wearers of a commonly prescribed 2-week replacement soft contact lens reported median wear experience VAS scores in the upper quartile for all assessments of vision and comfort and a median CLDEQ-8 score below that associated with dryness. Findings suggest that these lenses are a viable option for practitioners interested in the weekly replacement modality of soft lenses.

Purpose: Positive fusional vergence (PFV) is important for binocular fusion, yet the influence of illumination on near PFV remains underexplored. This study investigated the effect of different illumination levels on PFV parameters (blur, break, recovery) to provide insights that could help eye care professionals optimize clinical assessments and make recommendations for near-vision activities.

Methods: Using a within-subjects design, thirty young adults (mean age: 21.87 ± 2.79 years; range 18-30) with normal binocular vision were evaluated at the University of Benin Optometry Teaching Clinic. PFV was measured under three controlled lighting conditions (50, 100, and 150 lux) using a phoropter, photometer, and LED lighting system. Preliminary tests (visual acuity, cover test and Von Graefe phoria) preceded PFV measurement, with participants reporting blur, break, and recovery points. Data were analysed using Friedman and Wilcoxon Signed Ranks tests (SPSS v25.0; p < 0.05), with effect sizes calculated via rank-biserial correlation.

Results: PFV values significantly decreased with increasing illumination (all p < 0.001). At 50 lux, mean PFV measures were highest (blur: 12.93 ± 1.62^Δ, break: 22.87 ± 3.06^Δ, recovery: 15.67 ± 2.78^Δ). These declined progressively at 100 lux (blur: 11.40 ± 1.28^Δ; break: 20.80 ± 2.71^Δ; recovery: 14.07 ± 2.72^Δ) and 150 lux (blur: 10.27 ± 1.72^Δ; break: 18.83 ± 2.09^Δ; recovery: 12.70 ± 2.74^Δ). The steepest reductions occurred between 50 and 150 lux (blur: -20.5%; recovery: -19.0%), and rank-biserial correlations indicated large effect sizes (-0.798 to -1.000).

Conclusion: Higher illumination significantly reduces PFV, which suggests that lower-to-moderate lighting optimises binocular coordination during near tasks. These findings support adjusting ambient lighting in educational, occupational, and clinical settings to reduce visual fatigue during near tasks.

Purpose: The purposes of this study were to test the validity of a portable ultrasound biometer (6000 Scanmate-A, DGH Technology) against an optical biometer and to establish its repeatability and reproducibility on patients in sitting and supine positions.

Patients and methods: Healthy adults (N = 51) were recruited prospectively. At two study visits, Observer 1 made five measurements of AL and ACD in the right eye using an optical biometer (IOLMaster, Zeiss). Then two sets of three measurements of AL and ACD were made using the Scanmate-A, one while participants were sitting and another while they were supine. Observer 2 made the same measurements at one visit on a subset of participants (n = 42). Averages of the measurements were prepared for analysis (significance threshold set to α = 0.01) according to Bland and Altman, repeated-measures analyses of variance, linear correlations, and intraclass correlation coefficients (ICC).

Results: AL and ACD were significantly shorter when measured by the Scanmate-A (median [interquartile range] = 23.4 [22.5, 24.7] mm and mean ± standard deviation = 3.22 ± 0.45 mm, respectively) than when measured by IOLMaster (23.8 [23.1, 25.2] mm and 3.51 ± 0.33 mm, respectively). For both body positions, there were no differences in ACD and AL between visit 1 and visit 2. Correlations were strong between the visits, but the limits of agreement varied. Similarly, there were no significant differences between Observer 1 and Observer 2. Correlations and ICC were strong-to-moderate between the observers, and the limits of agreement varied.

Conclusion: Consistent with reports on other a-scan devices, the Scanmate-A measured shorter AL and shallower ACD than the IOLMaster. Although, mean or median AL and ACD did not differ across study visits, observers, and body positions, large limits of agreement on Bland-Altman analyses must be accounted for by users of the Scanmate-A.

Purpose: To evaluate the availability and utilization of the advanced equipment for the diagnosis and management of early keratoconus in the public and private healthcare facilities in Nyanza and Western Kenya.

Methods: A cross-sectional study design was applied. An online questionnaire was sent to the eyecare practitioners. Data on socio-demographics, equipment availability, and utilization for early keratoconus diagnosis and management were obtained and analyzed using SPSS V 29.

Results: A total of 134 eyecare practitioners (out of 143), with the majority 80 (59.7%) being males, responded to the questionnaire. The study found that advanced equipment were scarcely available, such as Tomographer 14 (10.4%), Topographer 17 (12.7%) and Pachymeter 21 (15.7%) as compared to basic equipment: distance VA chart 134 (100%), trial lens/phoropter 129 (96.3%), retinoscope 128 (95.5%) and slit-lamp 111 (82.8%), with level 6 having the highest availability. Additionally, the available advanced equipment had working conditions far below standards and below standards: topographer 6 (35.2%) and contact lens fitting set 12 (46.1%). The utilization rates of the advanced equipment were low as follows: contact lens fitting set 8 (31.0%), pachymeter 11 (52.4%) and topographer 9 (52.9%). A chi-square test found a significant association between equipment availability and their utilization, VA chart (p=0.03333), trial lens/phoropter (p=0.00292), slit-lamp (p=0.00283) and keratometer (p=0.00001).

Conclusion: The study revealed a lack of advanced diagnostic equipment, with some existing tools falling below standard and underutilized. It recommends that healthcare institutions prioritize the acquisition and maintenance of essential equipment. Additionally, the Ministry of Health should collaborate with stakeholders to incorporate early keratoconus detection into national eyecare guidelines.

Purpose: This study aimed to assess the effect of an external yellow-tinted filter (KIROS 1-400 lens) on visual function in patients with pre-perimetric glaucoma (PPG) and early primary open-angle glaucoma (POAG). The primary outcomes were contrast sensitivity (CS) and visual field (VF) indices assessed using standard automated perimetry (SAP).

Methods: This comparative observational, within-subject study included 30 patients with PPG (30 eyes) and 50 with POAG (50 eyes) recruited from the Ophthalmology Department of the 401 General Military Hospital, Athens, between January and December 2022. CS was measured using the Pelli-Robson chart. VF indices, including mean deviation (MD), pattern standard deviation (PSD), visual field index (VFI), and Glaucoma Hemifield Test (GHT) classifications, were assessed with SAP with the 24-2 SITA-standard strategy on the Humphrey Field Analyzer II 740. All testing was performed both with and without the yellow filter KIROS 1-400 (Essilor International) in the same eyes.

Results: The KIROS 1-400 filter significantly enhanced CS in both PPG and POAG eyes, increasing the median logCS by 0.03. However, while statistically significant, this improvement may not be clinically meaningful. In contrast, no significant changes were observed in the VF indices (MD, PSD, and VFI) when the filter was applied. Analysis of GHT results revealed that the filter reduced borderline classifications and showed high precision (0.733) and recall (0.846) for "outside normal limits" classifications. However, the agreement between the filtered and unfiltered GHT results was fair.

Conclusion: The KIROS 1-400 filter significantly enhanced CS in patients with PPG and POAG without notable effects on the VF indices. However, caution is advised when interpreting GHT results obtained with yellow-tinted filters. Further studies are recommended to evaluate the filter's long-term clinical benefits and its potential role in glaucoma management.

Purpose: This report aims to discuss a case involving family members diagnosed with Peters' anomaly, detailing the clinical characteristics, vision assessment, and rehabilitation.

Patients and methods: A family comprises two daughters and a son, were diagnosed with Peters' anomaly. Assessment included: visual and reading acuity, visual field, contrast sensitivity, and color vision. Different devices were employed based on each individual's visual needs and capabilities.

Results: The first daughter exhibited a visual acuity of 6/75 at distance and 6/95 at near in the better eye, along with a restricted visual field, moderate contrast sensitivity, and normal color vision. The second daughter had 6/60 visual acuity in both eyes, a restricted visual field, moderate contrast sensitivity, and abnormal color vision. Both girls were given a +12.00D binocular spectacle for near, and a telescope for distance, additionally, they were recommended to utilize a typoscope, felt pen, and reading stand for near tasks. The son had 6/75 vision at distance and near in both eyes, a restricted visual field, significantly reduced contrast sensitivity, and normal color vision. The son does not attend school; instead, he has been instructed in the use of a mobile phone application designed to magnify small print, and an 8x monocular telescope for distant viewing. He was also referred to a local organization that provides vocational training for young with disabilities. The father had 6/600 at distance and near in both eyes, a restricted visual field, severely reduced contrast sensitivity, and abnormal color vision. He received a video magnifier and advised to utilize bright illumination during reading and to use a cane while walking. The overwhelmed mother was referred to a counselling group for emotional support.

Conclusion: In low vision-rehabilitation, various interventions may be recommended to patients with the same condition based on their age, visual function, and targeted goals.

Serratia marcescens (S. marcescens) keratitis is a rare, sight-threatening infection primarily seen in contact lens users. A 22-year-old female developed sudden ocular symptoms two days after contact lens use. Examination revealed significant conjunctival injection, anterior chamber inflammation, and a corneal abscess with an epithelial defect. Despite initial moxifloxacin treatment, her condition worsened, requiring a switch to fortified vancomycin, ceftriaxone, and voriconazole. Cultures confirmed S. marcescens, allowing treatment to be streamlined to fortified ceftriaxone. The infection gradually resolved, with visual acuity returning to 20/20 and minimal residual scarring noted at one month.