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Journal of Clinical Medicine Apr 2023Color vision deficiency (CVD) is an under-reported problem among medical personnel, and its impact is still not well characterized. We aim to assess the impact of CVD...
BACKGROUND
Color vision deficiency (CVD) is an under-reported problem among medical personnel, and its impact is still not well characterized. We aim to assess the impact of CVD among ophthalmologists on the accuracy of diagnosing different benign and malignant choroidal lesions.
METHODS
This is a cross-sectional study conducted on ophthalmologists. We used a web-based survey to collect responses through professional ophthalmology society social media. The survey included a set of five images for normal fundus, choroidal nevus, circumscribed choroidal hemangioma, choroidal metastasis, and choroidal melanoma, wherein each image simulated the three main types of CVD: protanopia, deuteranopia, and tritanopia, in addition to a non-simulated image.
RESULTS
Forty-one participants were included, with a mean age of 40 (±9.2) years. They were 28 (68%) men and 13 (32%) women. Participants showed significantly low accuracy for definite diagnosis for circumscribed choroidal hemangioma, nevus, melanoma, and metastasis when the images simulated protanopia and deuteranopia, but not tritanopia. Nevertheless, participants maintained the capability to recognize the nature of the lesions for both simulated and non-simulated images if they were benign or malignant, thereby ensuring immediate referral for specialized care. The exception was with simulated choroidal nevi images, wherein participants incorrectly assigned simulated protanopia and deuteranopia nevi images to malignant lesions.
CONCLUSION
Protanopia and deuteranopia affected the accuracy of diagnosing several choroidal lesions; however, ophthalmologists with those two simulated CVDs were still able to discriminate between benign and malignant tumors.
PubMed: 37048826
DOI: 10.3390/jcm12072744 -
BMC Ophthalmology Apr 2023Peripapillary retinoschisis (PPRS) is often associated with glaucomatous eyes. It usually occurs in eyes with a more advanced stage of glaucoma with obvious optic nerve...
BACKGROUND
Peripapillary retinoschisis (PPRS) is often associated with glaucomatous eyes. It usually occurs in eyes with a more advanced stage of glaucoma with obvious optic nerve damage. We report a patient who was found to have PPRS in one eye during a routine physical examination without obvious glaucoma symptoms. Further examination revealed glaucomatous visual field loss and retinal nerve fiber layer defects in the contralateral eye.
CASE PRESENTATION
A 55-year-old man presented for a routine physical examination. The anterior segment was normal in both eyes. Fundus examination revealed an elevated and red optic disc in the right eye. In addition, scattered patchy red lesions were seen on the retina on the temporal side of the optic disc. The color and boundary of the left optic disc were normal, and the cup-to-disc ratio was 0.6. Optical coherence tomography showed retinoschisis on the optic nerve head of the right eye throughout the entire circumference, extending to the retina on the temporal side of the optic disc. The intraocular pressure was 18 mmHg OD and 19 mmHg OS. The patient was diagnosed with PPRS (OD). However, no optic disc pit or optic disc coloboma was found. Further examination showed that the visual field of the patient's right eye was generally normal, while a glaucomatous visual field defect was found in the left eye, which manifested as a nasal step visual field defect. Moreover, stereophotography and a red-free fundus image revealed two retinal nerve fiber layer defects in the supratemporal and infratemporal regions of the retina of the left eye. Continuous intraocular pressure measurement found that the intraocular pressure fluctuated between 18 and 22 mmHg OD and 19-26 mmHg OS during the daytime. Primary open-angle glaucoma was then diagnosed.
CONCLUSIONS
In this case, we found that PPRS was associated with glaucomatous optic nerve changes and visual field defects in the fellow eye.
Topics: Male; Humans; Middle Aged; Retinoschisis; Glaucoma, Open-Angle; Glaucoma; Optic Disk; Intraocular Pressure; Optic Nerve Injuries; Retinal Diseases; Tomography, Optical Coherence; Vision Disorders; Optic Nerve
PubMed: 37013512
DOI: 10.1186/s12886-023-02887-4 -
Ecotoxicology and Environmental Safety May 2023The widespread presence of mercury, a heavy metal found in the environment and used in numerous industries and domestic, raises concerns about its potential impact on...
The widespread presence of mercury, a heavy metal found in the environment and used in numerous industries and domestic, raises concerns about its potential impact on human health. Nevertheless, the adverse effects of this environmental toxicant at low concentrations are often underestimated. There are emerging studies showing that accumulation of mercury in the eye may contribute to visual impairment and a comorbidity between autism spectrum disorders (ASD) trait and visual impairment. However, the underlying mechanism of visual impairment in humans and rodents is challenging. In response to this issue, zebrafish larvae with a cone-dominated retinal visual system were exposed to 100 nM mercury chloride (HgCl), according to our previous study, followed by light-dark stimulation, a social assay, and color preference to examine the functionality of the visual system in relation to ASD-like behavior. Exposure of embryos to HgCl from gastrulation to hatching increased locomotor activity in the dark, reduced shoaling and exploratory behavior, and impaired color preference. Defects in microridges as the first barrier may serve as primary tools for HgCl toxicity affecting vision. Depletion of polyunsaturated fatty acids (PUFAs), linoleic acid, arachidonic acid (ARA), alpha-linoleic acid, docosahexaenoic acid (DHA), stearic acid, L-phenylalanine, isoleucine, L-lysine, and N-acetylputrescine, along with the increase of gamma-aminobutyric acid (GABA), sphingosine-1-phosphate, and citrulline assayed by liquid chromatography-mass spectrometry (LC-MS) suggest that these metabolites serve as biomarkers of retinal impairments that affect vision and behavior. Although suppression of adsl, shank3a, tsc1b, and nrxn1a gene expression was observed, among these tsc1b showed more positive correlation with ASD. Collectively, these results contribute new insights into the possible mechanism of mercury toxicity give rise to visual, cognitive, and social deficits in zebrafish.
Topics: Humans; Animals; Zebrafish; Mercury; Mercuric Chloride; Vision Disorders; Gene Expression
PubMed: 37004432
DOI: 10.1016/j.ecoenv.2023.114862 -
Vision Research Jul 2023Blue cone monochromacy (BCM) is a congenital vision disorder characterized by complete loss or severely reduced long- and middle-wavelength cone function, caused by... (Review)
Review
Blue cone monochromacy (BCM) is a congenital vision disorder characterized by complete loss or severely reduced long- and middle-wavelength cone function, caused by mutations in the OPN1LW/OPN1MW gene cluster on the X-chromosome. BCM patients typically suffer from poor visual acuity, severely impaired color discrimination, myopia, and nystagmus. In this review, we cover the genetic causes of BCM, clinical features of BCM patients, genetic testing, and clinical outcome measurements for future BCM clinical trials. However, our emphasis is on detailing the animal models for BCM and gene therapy using adeno-associated vectors (AAV). We describe two mouse models resembling the two most common causes of BCM, current progress in proof-of-concept studies to treat BCM with deletion mutations, the challenges we face, and future directions.
Topics: Animals; Mice; Color Vision Defects; Mutation; Genetic Therapy; Retinal Cone Photoreceptor Cells; Rod Opsins
PubMed: 37001420
DOI: 10.1016/j.visres.2023.108221 -
Journal of Ophthalmology 2023To evaluate the association between visual-related quality of life (VRQoL) and visual field (VF) loss in patients with primary angle-closure glaucoma (PACG).
PURPOSE
To evaluate the association between visual-related quality of life (VRQoL) and visual field (VF) loss in patients with primary angle-closure glaucoma (PACG).
METHODS
In this case-control study, a total of 79 patients with PACG (with or without VF detects) and 35 healthy controls were included. The patients underwent the 25-item National Eye Institute Visual Functioning Questionnaire (NEI VFQ-25), clinical examination, and VF testing. VF defects were identified by simplified Hodapp's classification. NEI VFQ-25 scores were compared between the three groups.
RESULTS
No significant differences were found in gender, VFQ rating for "composite score" and "color vision" between the three groups. PACG patients with VF loss were most likely to be older and had lower best corrected visual acuity (BCVA), spherical equivalent (SE), mean deviation (MD), and visual field index (VFI), but higher pattern standard deviation (PSD) (all < 0.05). Furthermore, patients with VF loss had significantly lower NVE-VFQ-25 subscale scores for general health, general vision, ocular pain, near activities, distance activities, social functioning, mental health, role difficulties, dependency, driving, and peripheral vision than PACG patients without VF loss and healthy controls (all < 0.05). VFI ( = 1.498, =0.003) and MD ( = -3.891, =0.016) were significantly correlated with Role Difficulties scores. Additionally, PSD was significantly correlated with Peripheral Vision scores ( = -1.346, =0.003).
CONCLUSIONS
PACG patients with VF loss reported lower NEI VFQ-25 composite and subscale scores. VF indices including VFI, MD, and PSD were strongly correlated with VRQoL as assessed by NEI VFQ-25; thus, VRQoL may be significantly impacted by glaucomatous VF defects.
PubMed: 36994448
DOI: 10.1155/2023/9981060 -
International Journal of Environmental... Mar 2023Since the 1960s, Grassy Narrows First Nation (Ontario, Canada) has been exposed to methyl mercury (Hg) through fish consumption, resulting from industrial pollution of...
Since the 1960s, Grassy Narrows First Nation (Ontario, Canada) has been exposed to methyl mercury (Hg) through fish consumption, resulting from industrial pollution of their territorial waters. This cross-sectional study describes the visual characteristics of adults with documented Hg exposure between 1970 and 1997. Oculo-visual examinations of 80 community members included visual acuity, automated visual fields, optical coherence tomography [OCT], color vision and contrast sensitivity. Median age was 57 years (IQR 51-63) and 55% of participants were women. Median visual acuity was 0.1 logMAR (Snellen 6/6.4; IQR 0-0.2). A total of 26% of participants presented a Visual Field Index inferior to 62%, and qualitative losses assessment showed concentric constriction (18%), end-stage concentric loss (18%), and complex defects (24%). On OCT, retinal nerve fiber layer scans showed 74% of participants within normal/green range. For color testing with the Hardy, Rand, and Rittler test, 40% presented at least one type of color defect, and with the Lanthony D-15 test, median color confusion index was 1.59 (IQR 1.33-1.96). Contrast sensitivity showed moderate loss for 83% of participants. These findings demonstrate important loss of visual field, color vision, and contrast sensitivity in older adults in a context of long-term exposure to Hg in Grassy Narrows First Nation.
Topics: Mercury; Dietary Exposure; Cross-Sectional Studies; Retina; Ontario
PubMed: 36981736
DOI: 10.3390/ijerph20064827 -
Genes Mar 2023Achromatopsia is a rare congenital condition with cone photoreceptor dysfunction causing color blindness, reduced vision, nystagmus and photophobia. New treatments are...
Achromatopsia is a rare congenital condition with cone photoreceptor dysfunction causing color blindness, reduced vision, nystagmus and photophobia. New treatments are being developed, but the current evidence is still conflicting regarding possible progression over time, and there is no clear genotype-phenotype correlation. This natural history study aimed to further explore the course of disease and potential clinical differences between various genotypes. The retrospective design allowed for the study of a large cohort with a long follow-up. Patients were identified from the Danish national registries. If not already available, genetic analysis was offered to the patient. Clinical data from 1945-2022 were retrieved from medical records and included best-corrected visual acuity (BCVA), color vision, refractive error, nystagmus, visual fields and fundoscopic findings. We identified variants believed to be disease causing in five of the known achromatopsia genes: ; ; ; and ; and novel variants were identified in and . Progressive deterioration of BCVA only attributable to achromatopsia was found in three of 58 patients. Progressive phenotype was seen with variants in and The results indicate that myopia could be more frequently occurring with variants in , and and support the evidence that achromatopsia is a predominantly stationary condition with respect to BCVA. Although a clear genotype-phenotype correlation can still not be concluded, there may be differences in phenotypical characteristics with variants in different genes.
Topics: Humans; Color Vision Defects; Retrospective Studies; Cyclic Nucleotide-Gated Cation Channels; Denmark
PubMed: 36980963
DOI: 10.3390/genes14030690 -
Current Biology : CB Apr 2023Most defects causing retinal degeneration in retinitis pigmentosa (RP) are rod-specific mutations, but the subsequent degeneration of cones, which produces loss of...
Most defects causing retinal degeneration in retinitis pigmentosa (RP) are rod-specific mutations, but the subsequent degeneration of cones, which produces loss of daylight vision and high-acuity perception, is the most debilitating feature of the disease. To understand better why cones degenerate and how cone vision might be restored, we have made the first single-cell recordings of light responses from degenerating cones and retinal interneurons after most rods have died and cones have lost their outer-segment disk membranes and synaptic pedicles. We show that degenerating cones have functional cyclic-nucleotide-gated channels and can continue to give light responses, apparently produced by opsin localized either to small areas of organized membrane near the ciliary axoneme or distributed throughout the inner segment. Light responses of second-order horizontal and bipolar cells are less sensitive but otherwise resemble those of normal retina. Furthermore, retinal output as reflected in responses of ganglion cells is less sensitive but maintains spatiotemporal receptive fields at cone-mediated light levels. Together, these findings show that cones and their retinal pathways can remain functional even as degeneration is progressing, an encouraging result for future research aimed at enhancing the light sensitivity of residual cones to restore vision in patients with genetically inherited retinal degeneration.
Topics: Humans; Retinal Degeneration; Retinal Cone Photoreceptor Cells; Retina; Retinitis Pigmentosa; Color Vision
PubMed: 36977418
DOI: 10.1016/j.cub.2023.03.007 -
IScience Mar 2023Charcot-Marie-Tooth disease type 2A (CMT2A), the most common inherited peripheral axonal neuropathy, is associated with more than 100 dominant mutations, including R94Q...
Charcot-Marie-Tooth disease type 2A (CMT2A), the most common inherited peripheral axonal neuropathy, is associated with more than 100 dominant mutations, including R94Q as the most abundant mutation in the Mitofusin2 (MFN2) gene. CMT2A is characterized by progressive motor and sensory loss, color-vision defects, and progressive loss of visual acuity. We used a well-established transgenic mouse model of CMT2A with R94Q mutation on MFN2 gene ( ) to investigate the functional and morphological changes in retina. We documented extensive vision loss due to photoreceptor degeneration, retinal ganglion cell and their axonal loss, retinal secondary neuronal and synaptic alternation, and Müller cell gliosis in the retina of mice. Imbalanced MFN1/MFN2 ratio and dysregulated mitochondrial fusion/fission result in retinal degeneration via P62/LC3B-mediated mitophagy/autophagy in mice. Finally, transgenic MFN1 augmentation ( :) rescued vision and retinal morphology to wild-type level via restoring homeostasis in mitochondrial MFN1/MFN2 ratio, fusion/fission cycle, and PINK1-dependent, Parkin-independent mitophagy.
PubMed: 36936780
DOI: 10.1016/j.isci.2023.106270