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Scientific Reports Apr 2024Primary congenital glaucoma is a rare disease that occurs in early birth and can lead to low vision. Evaluating affected children is challenging and there is a lack of...
Primary congenital glaucoma is a rare disease that occurs in early birth and can lead to low vision. Evaluating affected children is challenging and there is a lack of studies regarding color vision in pediatric glaucoma patients. This cross-sectional study included 21 eyes of 13 children with primary congenital glaucoma who were assessed using the Farnsworth D-15 test to evaluate color vision discrimination and by spectral domain optical coherence tomography to measure retinal fiber layer thickness. Age, visual acuity, cup-to-disc ratio and spherical equivalent data were also collected. Global and sectional circumpapillary and macular retinal fiber layer thicknesses were measured and compared based on color vision test performance. Four eyes (19%) failed the color vision test with diffuse dyschromatopsia patterns. Only age showed statistical significance in color vision test performance. Global and sectional circumpapillary and macular retinal fiber layer thicknesses were similar between the color test outcomes dyschromatopsia and normal. While the color vision test could play a role in assessing children with primary congenital glaucoma, further studies are needed to correlate it with damage to retinal fiber layer thickness.
Topics: Humans; Female; Male; Child; Cross-Sectional Studies; Tomography, Optical Coherence; Glaucoma; Child, Preschool; Color Vision; Visual Acuity; Adolescent; Color Vision Defects; Color Perception; Retina; Color Perception Tests
PubMed: 38664551
DOI: 10.1038/s41598-024-60320-2 -
Taiwan Journal of Ophthalmology 2024Ocular comorbidities can happen as congenital defective gene associations. We present a 37-year-old female patient who was mentally challenged and had coexisting...
Ocular comorbidities can happen as congenital defective gene associations. We present a 37-year-old female patient who was mentally challenged and had coexisting achromatopsia gene abnormality on genetic analysis. She was operated in childhood for congenital cataract, and posterior chamber intraocular lens (IOL) was implanted at 10 years of age elsewhere. The patient presented 27 years later with luxated IOL with endothelial decompensation. There was a coexisting steep and thin cornea noted on corneal topography. She was managed with pre-Descemet's endothelial keratoplasty with transpositioning of posterior chamber IOL to glued IOL with single-pass four-throw pupilloplasty. Postoperatively, the cornea was clear with centered glued IOL. The lesser postanesthetic challenges and faster rehabilitation are obtained in combination procedures with reduced complications in such rare scenarios.
PubMed: 38655000
DOI: 10.4103/tjo.TJO-D-23-00172 -
Yi Chuan = Hereditas Apr 2024Red-green colour blindness is a classic example for the teaching of X-linked recessive inheritance in genetics course. However, there are lots of types of color vision...
Red-green colour blindness is a classic example for the teaching of X-linked recessive inheritance in genetics course. However, there are lots of types of color vision deficiencies besides red-green colour blindness. Different color vision deficiencies caused by different genes may have different modes of inheritance. In recent years, many research achievements on colour blindness have been made. These achievements could be used as teaching resources in genetics course. Here, we summarize the construction of genetics teaching resources related to colour blindness and their application in genetics teaching in several chapters such as introduction, cellular and molecular basis of genetics, sex-linked inheritance, chromosomal aberration, gene mutation and advances in genetics. Teacher could use the resources in class or after class with different teaching methods such as questioning teaching method and task method. It may expand students' academic horizons and inspire students' interest in genetics besides grasping basic genetic knowledge.
Topics: Humans; Color Vision Defects; Mutation; Chromosome Aberrations; Teaching; Genetics
PubMed: 38632096
DOI: 10.16288/j.yczz.24-017 -
Investigative Ophthalmology & Visual... Apr 2024Achromatopsia (ACHM) is an autosomal recessive retinal disease associated with reduced or absent cone function. There is debate regarding the extent to which cone...
PURPOSE
Achromatopsia (ACHM) is an autosomal recessive retinal disease associated with reduced or absent cone function. There is debate regarding the extent to which cone structure shows progressive degeneration in patients with ACHM. Here, we used optical coherence tomography (OCT) images to evaluate outer nuclear layer (ONL) thickness and ellipsoid zone (EZ) integrity over time in individuals with ACHM.
METHODS
Sixty-three individuals with genetically confirmed ACHM with follow-up ranging from about 6 months to 10 years were imaged using either Bioptigen or Cirrus OCT. Foveal cone structure was evaluated by assessing EZ integrity and ONL thickness.
RESULTS
A total of 470 OCT images were graded, 243 OD and 227 OS. The baseline distribution of EZ grades was highly symmetrical between eyes (P = 0.99) and there was no significant interocular difference in baseline ONL thickness (P = 0.12). The EZ grade remained unchanged over the follow-up period for 60 of 63 individuals. Foveal ONL thickness showed a clinically significant change in only 1 of the 61 individuals analyzed, although detailed adaptive optics imaging revealed no changes in cone density in this individual.
CONCLUSIONS
ACHM appears to be a generally stable condition, at least over the follow-up period assessed here. As cones are the cellular targets for emerging gene therapies, stable EZ and ONL thickness demonstrate therapeutic potential for ACHM, although other aspects of the visual system need to be considered when determining the best timing for therapeutic intervention.
Topics: Humans; Color Vision Defects; Tomography, Optical Coherence; Retinal Cone Photoreceptor Cells; Fovea Centralis; Retina
PubMed: 38587442
DOI: 10.1167/iovs.65.4.16 -
Japanese Journal of Ophthalmology May 2024To identify the ophthalmic causes of congenital nystagmus with normal eye examination by electroretinography (ERG). (Observational Study)
Observational Study
PURPOSE
To identify the ophthalmic causes of congenital nystagmus with normal eye examination by electroretinography (ERG).
STUDY DESIGN
Retrospective observational study.
METHODS
We reviewed the medical records of patients younger than 6 months of age who presented between June 2008 and November 2011 with nystagmus and no other neurological signs following an otherwise normal eye examination. A complete ophthalmic examination and ERG (Nicolet Bravo system; Nicolet Biomedial & RETIscan; Roland Instruments), fundus photography, and Ishihara color test were performed to identify any ophthalmic causes of congenital nystagmus.
RESULTS
Thirty-three patients met the criteria. Rod dysfunction was diagnosed in 4 patients (12.1%), cone dysfunction in 2 patients (6.1%), and cone-rod dysfunction in 1 patient (3.0%). The results of ERG were negative in 2 patients (6.1%). Idiopathic infantile nystagmus was diagnosed in the remaining 24 patients (72.7%) based on their normal ERG examination.
CONCLUSIONS
In Korean congenital nystagmus patients with a normal fundus examination, achromatopsia and Leber's congenital amaurosis are uncommon causes. ERG is needed to make a definite diagnosis and provide prognostic information in congenital idiopathic nystagmus patients with a normal fundus examination.
Topics: Humans; Electroretinography; Retrospective Studies; Female; Male; Nystagmus, Congenital; Fundus Oculi; Infant; Retina; Visual Acuity
PubMed: 38568447
DOI: 10.1007/s10384-024-01058-2 -
Investigative Ophthalmology & Visual... Apr 2024To describe and evaluate a novel method to determine the validity of measurements made using cycle-by-cycle (CxC) recording techniques in patients with advanced retinal...
PURPOSE
To describe and evaluate a novel method to determine the validity of measurements made using cycle-by-cycle (CxC) recording techniques in patients with advanced retinal degenerations (RD) having low-amplitude flicker electroretinogram (ERG) responses.
METHODS
The method extends the original CxC recording algorithm introduced by Sieving et al., retaining the original recording setup and the preliminary analysis of raw data. Novel features include extended use of spectrum analysis, reduction of errors due to known sources, and a comprehensive statistical assessment using three different tests. The method was applied to ERG recordings from seven patients with RD and two patients with CNGB3 achromatopsia.
RESULTS
The method was implemented as a Windows application to processes raw data obtained from a commercial ERG system, and it features a computational toolkit for statistical assessment of ERG recordings with amplitudes as low as 1 µV, commonly found in advanced RD patients. When recorded using conditions specific for eliciting cone responses, none of the CNGB3 patients had a CxC validated response, indicating that no signal artifacts were present with our recording conditions. A comparison of the presented method with conventional 30 Hz ERG was performed. Bland-Altman plots indicated good agreement (mean difference, -0.045 µV; limits of agreement, 0.193 to -0.282 µV) between the resulting amplitudes. Within-session test-retest variability was 15%, comparing favorably to the variability of standard ERG amplitudes.
CONCLUSIONS
This novel method extracts highly reliable clinical recordings of low-amplitude flicker ERGs and effectively detects artifactual responses. It has potential value both as a cone outcome variable and planning tool in clinical trials on natural history and treatment of advanced RDs.
Topics: Humans; Electroretinography; Retinal Degeneration; Retinal Cone Photoreceptor Cells; Color Vision Defects; Photic Stimulation; Retina
PubMed: 38558093
DOI: 10.1167/iovs.65.4.3 -
Vision Research May 2024Manufacturers of notch filter-based aids for color vision claim that their products can enhance color perception for people with anomalous trichromacy, a form of color...
Manufacturers of notch filter-based aids for color vision claim that their products can enhance color perception for people with anomalous trichromacy, a form of color vision deficiency (CVD). Anecdotal reports imply that people with CVD can have radically enhanced color vision when using the filters. However, existing empirical research largely focussed on the effect of notch filters on performance on diagnostic tests for CVD has not found that they have any substantial effect. Informed by a model of anomalous trichromatic color vision, we selected stimuli predicted to reveal the effects of EnChroma filters. Using these stimuli, we tested the ability of EnChroma filters to enhance color vision for 10 deuteranomalous trichromats in three experiments: 1. asymmetric color matching between test and control filter conditions, 2. color discrimination measured using four alternative forced-choice, and 3. color appearance measured using dissimilarity ratings to reconstruct subjective color spaces using multidimensional scaling. To investigate potential effects of long-term adaptation or perceptual learning, participants completed all three experiments at two time points, on first exposure to the filters, and after a week of regular use. We found a significant effect of the filters on color matches in the direction predicted by the model at both time points, implying that the filters can enhance the anomalous trichromatic color gamut. However, we found minimal effect of the filters on color discrimination at threshold. We found a significant effect of the filters in enhancing the appearance of colors along the red-green axis at the first time point, and a trend in the same direction at the second time point. Our results provide the first quantitative experimental evidence that notch filters can enhance color perception for anomalous trichromats.
Topics: Humans; Color Vision; Color Perception Tests; Color Vision Defects; Color Perception; Cardiovascular Diseases; Color
PubMed: 38531192
DOI: 10.1016/j.visres.2024.108390 -
Ophthalmology. Retina Mar 2024To examine the molecular causes of Schubert-Bornschein (S-B) congenital stationary night blindness (CSNB), clinically characterize in detail, and assess...
OBJECTIVE
To examine the molecular causes of Schubert-Bornschein (S-B) congenital stationary night blindness (CSNB), clinically characterize in detail, and assess genotype-phenotype correlations for retinal function and structure.
DESIGN
Retrospective, longitudinal, single-center case series.
PARTICIPANTS
One hundred twenty-two patients with S-B CSNB attending Moorfields Eye Hospital, United Kingdom.
METHODS
All case notes, results of molecular genetic testing, and OCT were reviewed.
MAIN OUTCOME MEASURES
Molecular genetics, presenting complaints, rates of nystagmus, nyctalopia, photophobia, strabismus, color vision defects and spherical equivalent refraction (SER). Retinal thickness, outer nuclear layer (ONL) thickness, and ganglion cell layer + inner plexiform layer (GCL+IPL) thickness from OCT imaging.
RESULTS
X-linked (CACNA1F and NYX) and autosomal recessive (TRPM1, GRM6, GPR179 and CABP4) genotypes were identified. The mean (± standard deviation) reported age of onset was 4.94 ± 8.99 years. Over the follow-up period, 95.9% of patients reported reduced visual acuity (VA), half had nystagmus, and 64.7% reported nyctalopia. Incomplete CSNB (iCSNB) patients more frequently had nystagmus and photophobia. Nyctalopia was similar for iCSNB and complete CSNB (cCSNB). Color vision data were limited but more defects were found in iCSNB. None of these clinical differences met statistical significance. There was no significant difference between groups in VA, with a mean of 0.46 logarithm of the minimum angle of resolution, and VA remained stable over the course of follow-up. Complete congenital stationary night blindness patients, specifically those with NYX and TRPM1 variants, were more myopic. CACNA1F patients showed the largest refractive variability, and the CABP4 patient was hyperopic. No significant differences were found in OCT structural analysis during the follow-up period.
CONCLUSIONS
Retinal structure in CSNB is stationary and no specific genotype-structure correlates were identified. Visual acuity seems to be relatively stable, with rare instances of progression.
FINANCIAL DISCLOSURE(S)
Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.
PubMed: 38522615
DOI: 10.1016/j.oret.2024.03.017 -
Vision Research May 2024EnChroma filters are aids designed to improve color vision for anomalous trichromats. Their use is controversial because the results of lab-based assessments of their...
EnChroma filters are aids designed to improve color vision for anomalous trichromats. Their use is controversial because the results of lab-based assessments of their effectiveness have so far largely failed to agree with positive anecdotal reports. However, the effectiveness of EnChroma filters will vary depending on the conditions of viewing, including whether the stimuli are broadband reflective surfaces or colors presented on RGB displays, whether illumination spectra are broadband or narrowband, the transmission spectra of particular filters, and the cone spectral sensitivity functions of the observer. We created a model of anomalous trichromatic color vision to predict the effects of EnChroma filters on the color signals impaired in anomalous trichromacy. Using the model we varied illumination, filter type and observer cone sensitivity functions, and tested the effect of presenting colors as broadband reflective surfaces or on RGB displays. We also used hyperspectral images to assess the impact of the filters on anomalous trichromats' color vision for natural scenes. Model results predicted that the filters should be broadly effective at enhancing anomalous trichromats' equivalent to L/(L + M) chromatic contrasts under a range of viewing conditions, but are substantially more effective for deuteranomals than for protanomals. The filters are predicted to be more effective for broadband reflective surfaces presented under broadband illuminants than for surfaces presented under narrowband illuminants or for colors presented on RGB displays. Since the potential impacts of contrast adaptation and perceptual learning are not considered in the model, it needs to be empirically validated. Results of empirical tests of the effects of EnChroma filters on deuteranomalous color vision in comparison with model predictions are presented in an accompanying paper (Somers et al., in prep.).
Topics: Humans; Color Perception; Color Perception Tests; Color Vision Defects; Retinal Cone Photoreceptor Cells; Color Vision; Color
PubMed: 38522412
DOI: 10.1016/j.visres.2024.108381 -
Should Colour Vision Deficiency be a Factor for Considering Admission to Nursing Education Programs?Journal of the College of Physicians... Mar 2024Null.
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Topics: Humans; Color Vision Defects; Education, Nursing
PubMed: 38462884
DOI: 10.29271/jcpsp.2024.03.379