Xanthopsia Due to Digoxin Toxicity as a Cause of Traffic Accidents: A Case Report.

BACKGROUND Manifestations of digoxin toxicity vary, such as cardiac disturbances and gastrointestinal symptoms, and most are not specific to digoxin toxicity. We report a case of xanthopsia (yellow vision), a rare and relatively specific manifestation of digoxin toxicity, causing traffic accidents. CASE REPORT A 76-year-old man was admitted to our hospital for treatment of heart failure. He reported that his digoxin dose had been increased from 0.125 mg daily to 0.25 mg daily 3 weeks before admission. His serum digoxin level was 7.3 ng/mL (therapeutic range 0.8 to 2.0). Additional history-taking revealed that he had xanthopsia several days before admission and stopped riding a motorbike because of two traffic accidents. On ophthalmological examination, he had decreased responses on flash, cone, and 30-Hz flicker electroretinograms in both eyes without visual field impairment. Intravenous hydration was initiated and digoxin was withdrawn. Xanthopsia gradually improved along with the decline of serum digoxin levels and disappeared within a week. One month after admission, electroretinography findings were normal. CONCLUSIONS Our case highlights the importance of acknowledging color vision deficiencies due to digoxin toxicity even in the modern era. This condition may increase risk of adverse events because affected patients are less likely to recognize color vision deficiencies.

Ethionamide induced blue vision (cyanopsia): Case report.

Ethionamide is part of a group of drugs used in the treatment of drug resistant TB. With the advent of increasing drug resistance in pulmonary TB cases, use of Ethionamide, a second line anti tubercular drug is increasing. Vision changes are rare with ethionamide. Cyanopsia i.e., bluish tinted vision of surroundings with ethionamide is not known in literature. Here, we report a case of DRTB patient who developed cyanopsia soon after introducing ethionamide. Although reversible, ethionamide may sometimes need withdrawal because of significant distress caused to patient.

Blue-yellow dyschromatopsia in toluene-exposed workers.

PURPOSE: To evaluate the effects of a chronic occupational exposure to toluene on color vision. METHODS: Color vision was tested in 51 workers exposed to pure toluene and in 51 matched control subjects. Current exposure was determined by biological monitoring. Blood samples were taken at the end of a Friday shift. Color vision ability was assessed using the Ishihara plates (to screen for congenital dyschromatopsia), the Farnsworth panel D-15 test, the Lanthony panel D-15 desaturated test, the Velhagen plates, and the Standard Pseudoisochromatic Plates Part 2. RESULTS: Median toluene concentration was 1.59 mg/l (quartiles 0.78 and 2.65). The whole group of workers did not perform worse than the controls. The same applies to 20 printers, who regularly assessed hues. Assessed with the most sensitive Lanthony panel D-15 desaturated test, color vision of 24 permanently exposed assistants was impaired (median color confusion index of the 1st eyes 1.08 vs. 1.02, p < 0.02; 2nd eyes 1.08 vs. 1.0, p < 0.05; sign test). The assistants made almost exclusively blue-yellow errors. The other color vision tests did not reveal any differences between the groups. CONCLUSION: Changes in the retina are a possible explanation for the observed blue-yellow dyschromatopsia.

Color vision impairment with low-level methylmercury exposure of an Amazonian population - Brazil.

Land exploitation that follows deforestation and mining can result in soil erosion and the release of mercury to the waters of rivers in the Amazon Basin. Inorganic mercury is methylated by bacteria that are present in the environment and it serves as a source of human contamination through fish consumption in the form of methylmercury. Long-term exposure to low-level methylmercury in the riverside populations can lead to nervous system alterations, some of which are visual impairments such as loss of luminance contrast sensitivity, restricted visual fields and color vision defects. The present study sought to examine color vision in a group of adults living in the central Brazilian Amazon who were exposed to low-levels of methylmercury. Total Hg concentrations were measured from hair collected at the time of the testing. The D15d and FM100 color vision arrangement tests were applied in a population of 36 (22 males) and 42 (25 males), respectively. Controls were healthy volunteers from the cities of São Paulo for the D15d and Belém for the FM100. There was a statistically significant difference in performance between those who were exposed and controls for both tests (p < 0.01 and p < 0.0001, respectively, Mann-Whitney U test), meaning that adults living in this region of the Amazon made more mistakes on both tests when compared to controls. A linear regression was performed using Hg concentrations and test scores. Hg concentrations accounted for 7% and 2% of color D15d and FM100 arrangement test errors, respectively. Although other studies have previously found color vision impairment in the Amazon, they tested inhabitants on the east side of the Amazon, while this study was conducted in the central Amazon region and it is the first study in a population with no direct contact with the Hg source of contamination. These results suggest that long-term exposure to low-level methylmercury in riverside populations is more widely spread in the Amazon Basin than previously reported. This information is needed to implement public health policies that will ensure a safer environment for the Amazonian population.

Occupational styrene exposure and acquired dyschromatopsia: A systematic review and meta-analysis.

BACKGROUND: Styrene is a chemical used in the manufacture of plastic-based products worldwide. We systematically reviewed eligible studies of occupational styrene-induced dyschromatopsia, qualitatively synthesizing their findings and estimating the exposure effect through meta-analysis. METHODS: PubMed, EMBASE, and Web of Science databases were queried for eligible studies. Using a random effects model, we compared measures of dyschromatopsia between exposed and non-exposed workers to calculate the standardized mean difference (Hedges'g). We also assessed between-study heterogeneity and publication bias. RESULTS: Styrene-exposed subjects demonstrated poorer color vision than did the non-exposed (Hedges' g = 0.56; 95%CI: 0.37, 0.76; P < 0.0001). A non-significant Cochran's Q test result (Q = 23.2; P = 0.171) and an I2 of 32.2% (0.0%, 69.9%) indicated low-to-moderate between-study heterogeneity. Funnel plot and trim-and-fill analyses suggested publication bias. CONCLUSIONS: This review confirms the hypothesis of occupational styrene-induced dyschromatopsia, suggesting a modest effect size with mild heterogeneity between studies.

Discromatopsias y exposición a solventes orgánicos: una revisión sistemática / Impaired colour vision in workers exposed to organic solvents: a systematic review

OBJETIVO: Evaluar la evidencia reciente sobre la relación entre la exposición a solventes orgánicos y la alteración en la visión de colores. MÉTODOS: Se realizó una búsqueda bibliográfica de artículos científicos publicados en los últimos 15 años, en las bases de datos Lilacs, Pubmed, Science Direct, Cochrane y EBSCO de estudios observacionales que evaluaran la asociación entre las alteraciones en la visión de colores y la exposición a solventes orgánicos. RESULTADOS: En total se seleccionaron 11 estudios realizados en población laboralmente activa, que utilizaron el test de Lanthony desaturado D-15 (D-15d), midieron la exposición a solventes orgánicos e incluyeron controles no expuestos. Se encontró que existe una relación estadísticamente significativa entre la exposición a solventes orgánicos y la presencia de alteraciones en la visión de colores. CONCLUSIONES: Los resultados encontrados apoyan la hipótesis de que la exposición a solventes orgánicos podría inducir discromatopsias adquiridas. Evaluar la visión de colores con el test D-15d es simple y sensible para el diagnóstico. Se hace necesaria la realización de más estudios sobre el tema que ayuden a entender mejor la relación entre la alteración de la visión de colores y los efectos adversos más severos causados por esta exposición

OBJECTIVE: To evaluate recent evidence concerning the relationship between the exposure to organic solvents and the impairment of colour vision. METHODS: A bibliographic search was conducted for scientific papers published in the last 15 years, in the LILACS, PubMed, Science Direct, EBSCO, and Cochrane databases that included observational studies assessing the relationship between impairment in colour vision and exposure to organic solvents. RESULTS: Eleven studies were selected that were performed on an economically active population and used the Lanthony D-15 desaturated test (D-15d), measured the exposure to organic solvents, and included unexposed controls. It was found that there is a statistically significant relationship between the exposure to organic solvents and the presence of an impairment in colour vision. CONCLUSIONS: The results support the hypothesis that exposure to organic solvents could induce acquired dyschromatopsia. The evaluation of colour vision with the D-15d test is simple and sensitive for diagnosis. More studies need to be conducted on this subject in order to better understand the relationship between impaired colour vision and more severe side effects caused by this exposure

Multichannel perimetric alterations in systemic lupus erythematosus treated with hydroxychloroquine.

Systemic lupus erythematosus (SLE) is a multiorgan autoimmune disease of unknown etiology with many clinical manifestations. We report the first case of SLE in which visual alterations were evaluated with multichannel perimetry. Some achromatic and color vision alterations may be present in SLE, especially when treated with hydroxychloroquine. The sensitivity losses detected in the chromatic channels in the central zone of the visual field were consistent with the results of the FM 100 Hue color test. Likewise, the multichannel perimetry detected sensitivity losses in the parafoveal area for both chromatic channels, especially for the blue-yellow.

Impaired colour vision in workers exposed to organic solvents: A systematic review. / Discromatopsias y exposición a solventes orgánicos: una revisión sistemática.

OBJECTIVE: To evaluate recent evidence concerning the relationship between the exposure to organic solvents and the impairment of colour vision. METHODS: A bibliographic search was conducted for scientific papers published in the last 15 years, in the LILACS, PubMed, Science Direct, EBSCO, and Cochrane databases that included observational studies assessing the relationship between impairment in colour vision and exposure to organic solvents. RESULTS: Eleven studies were selected that were performed on an economically active population and used the Lanthony D-15 desaturated test (D-15d), measured the exposure to organic solvents, and included unexposed controls. It was found that there is a statistically significant relationship between the exposure to organic solvents and the presence of an impairment in colour vision. CONCLUSIONS: The results support the hypothesis that exposure to organic solvents could induce acquired dyschromatopsia. The evaluation of colour vision with the D-15d test is simple and sensitive for diagnosis. More studies need to be conducted on this subject in order to better understand the relationship between impaired colour vision and more severe side effects caused by this exposure.

Acquired Color Vision Defects and Hexane Exposure: A Study of San Francisco Bay Area Automotive Mechanics.

Occupational exposure to solvents, including n-hexane, has been associated with acquired color vision defects. Blue-yellow defects are most common and may be due to neurotoxicity or retinal damage. Acetone may potentiate the neurotoxicity of n-hexane. We present results on nonhexane solvent and hexane exposure and color vision from a cross-sectional study of 835 automotive repair workers in the San Francisco Bay Area, California (2007-2013). Cumulative exposure was estimated from self-reported work history, and color vision was assessed using the Lanthony desaturated D-15 panel test. Log-binomial regression was used to estimate prevalence ratios for color vision defects. Acquired color vision defects were present in 29% of participants, of which 70% were blue-yellow. Elevated prevalence ratios were found for nonhexane solvent exposure, with a maximum of 1.31 (95% confidence interval (CI): 0.86, 2.00) for blue-yellow. Among participants aged ≤50 years, the prevalence ratio for blue-yellow defects was 2.17 (95% CI: 1.03, 4.56) in the highest quartile of nonhexane solvent exposure and 1.62 (95% CI: 0.97, 2.72) in the highest category of exposure to hexane with acetone coexposure. Cumulative exposures to hexane and nonhexane solvents in the highest exposure categories were associated with elevated prevalence ratios for color vision defects in younger participants.

[Early effects of PCE exposure on visual function among dry cleaning workers]. / Effetti precoci della esposizione e percloroetilene nei lavoratori delle levanderie a secco sulla funzione visiva.

BACKGROUND: A number of studies have shown a possible correlation between exposure to perchlorethylene (PCE) in dry cleaning workers and impairment of colour perception. OBJECTIVES: to ascertain the possible presence of alterations in visual function in a group of workers exposed to current limit value levels of PCE. METHODS: The study was conducted on 38 workers exposed to PCE in 21 dry cleaning establishments in the district of Modena and 60 controls selected according to criteria of comparability. We measured exposure to PCE among the dry cleaning workers using environmental monitoring (mean exposure 16.9 mg/m3). Both groups then answered a medical history questionnaire and underwent the Ishihara test for evaluating exclusion criteria followed by Lanthony D15d and Visual Acuity in Contrast Reduced (VCS) tests to evaluate changes in visual function. The results of Lanthony's test were expressed using Index Confusion Chromatic (ICC). RESULTS: In the cases the average value of ICC was 1.28 (DS 0.21) and in the controls 1.15 (SD 0.21); the difference was statistically significant (p <0.01). The values of ICC tended to be worse in subjects engaged only in the washing phase, who also had higher levels of exposure to PCE (mean exposure 26.8 mg/m3). The values of VCS for each frequency did not show, however, significant differences between the two groups. CONCLUSIONS: On this basis, our data indicate that occupational exposure to PCE well below the current limit values may still be able to induce impairment of colour perception and that such levels are therefore not adequately protective, at least against these effects.

Retinal toxicity of high-dose hydroxychloroquine in patients with chronic graft-versus-host disease.

OBJECTIVE: To evaluate retinal toxicity in patients treated with high-dose hydroxychloroquine (HCQ) (Plaquenil, Sanofi Pharmaceuticals) for chronic graft-versus-host disease (GVHD). DESIGN: Cohort study. PARTICIPANTS: Twelve patients with chronic GVHD treated with 800 mg/day HCQ between June 2005 and December 2010. METHODS: Patients in this study underwent ophthalmologic examination yearly and ancillary studies including colour vision, Amsler grid, fundus photographs, Humphrey 10-2 automated perimetry, spectral-domain optical coherence tomography (SD-OCT), and multifocal electroretinography (mfERG). Evidence of HCQ toxicity was determined by the presence of scotomas in the Amsler grid and Humphrey 10-2 automated perimetry, and confirmed by at least 1 objective test including SD-OCT or mfERG. RESULTS: Of the 12 patients, 7 were male and 5 were female. Mean age was 49 years. Mean best corrected visual acuity at baseline was 20/25 and remained 20/25 at final follow-up. Median duration of HCQ treatment was 22.8 months. Median adjusted daily dosage was 11.5 mg/kg/day. Seven patients developed vortex keratopathy. No signs of pigmentary retinopathy or bull's-eye maculopathy were found in any of the patients. Three patients developed retinal toxicity with scotomas in the Amsler grid and Humphrey 10-2 automated perimetry, as well as abnormal mfERG. Retinal structure measured by SD-OCT was abnormal in 2 of the 3 patients with retinal toxicity. Colour vision measured by Ishihara plates, as well as by 100 Hue colour test, was abnormal in 2 of the 3 patients with retinal toxicity. CONCLUSIONS: High-dose HCQ in patients with GVHD was associated with higher incidence and earlier development of retinal toxicity.

Linezolid induced retinopathy.

PURPOSE: While optic neuropathy is a well-known cause of visual disturbances in linezolid-treated patients, the possibility of linezolid-related retinopathy has not been investigated. Here, we report a case of retinopathy demonstrated by multifocal electroretinogram (mfERG) in a linezolid-treated patient. METHOD AND RESULTS: A 61-year-old man with extensively drug-resistant pulmonary tuberculosis treated with linezolid for 5 months presented with painless loss of vision in both eyes. The patient's best corrected visual acuity was 20/50 in the right eye and 20/100 in the left eye. Fundus examination revealed mild disc edema, and color vision was defective in both eyes. Humphrey visual field tests showed a superotemporal field defect in the right eye and central and pericentral field defect in the left eye. Optical coherence tomography (OCT) revealed only mild optic disc swelling. In mfERG, central amplitudes were depressed in both eyes. Four months after the cessation of linezolid, visual acuity was restored to 20/20 right eye and 20/25 left eye. The color vision and visual field had improved. The OCT and mfEFG findings improved as well. CONCLUSIONS: Although the clinical features were similar to linezolid-induced optic neuropathy, the mfERG findings suggest the possibility of a retinopathy through cone dysfunction.

Colour Vision Impairment in Young Alcohol Consumers.

Alcohol consumption among young adults is widely accepted in modern society and may be the starting point for abusive use of alcohol at later stages of life. Chronic alcohol exposure can lead to visual function impairment. In the present study, we investigated the spatial luminance contrast sensitivity, colour arrangement ability, and colour discrimination thresholds on young adults that weekly consume alcoholic beverages without clinical concerns. Twenty-four young adults were evaluated by an ophthalmologist and performed three psychophysical tests to evaluate their vision functions. We estimated the spatial luminance contrast sensitivity function at 11 spatial frequencies ranging from 0.1 to 30 cycles/degree. No difference in contrast sensitivity was observed comparing alcohol consumers and control subjects. For the evaluation of colour vision, we used the Farnsworth-Munsell 100 hue test (FM 100 test) to test subject's ability to perform a colour arrangement task and the Mollon-Reffin test (MR test) to measure subject's colour discrimination thresholds. Alcohol consumers made more mistakes than controls in the FM100 test, and their mistakes were diffusely distributed in the FM colour space without any colour axis preference. Alcohol consumers also performed worse than controls in the MR test and had higher colour discrimination thresholds compared to controls around three different reference points of a perceptually homogeneous colour space, the CIE 1976 chromaticity diagram. There was no colour axis preference in the threshold elevation observed among alcoholic subjects. Young adult weekly alcohol consumers showed subclinical colour vision losses with preservation of spatial luminance contrast sensitivity. Adolescence and young adult age are periods of important neurological development and alcohol exposure during this period of life might be responsible for deficits in visual functions, especially colour vision that is very sensitive to neurotoxicants.

Styrene-associated health outcomes at a windblade manufacturing plant.

BACKGROUND: Health risks of using styrene to manufacture windblades for the green energy sector are unknown. METHODS: Using data collected from 355 (73%) current windblade workers and regression analysis, we investigated associations between health outcomes and styrene exposure estimates derived from urinary styrene metabolites. RESULTS: The median current styrene exposure was 53.6 mg/g creatinine (interquartile range: 19.5-94.4). Color blindness in men and women (standardized morbidity ratios 2.3 and 16.6, respectively) was not associated with exposure estimates, but was the type previously reported with styrene. Visual contrast sensitivity decreased and chest tightness increased (odds ratio 2.9) with increasing current exposure. Decreases in spirometric parameters and FeNO, and increases in the odds of wheeze and asthma-like symptoms (odds ratios 1.3 and 1.2, respectively) occurred with increasing cumulative exposure. CONCLUSIONS: Despite styrene exposures below the recommended 400 mg/g creatinine, visual and respiratory effects indicate the need for additional preventative measures in this industry.

SAFETY PROFILE OF OCRIPLASMIN FOR SYMPTOMATIC VITREOMACULAR ADHESION: A Comprehensive Analysis of Premarketing and Postmarketing Experiences.

PURPOSE: After the recent approval of ocriplasmin by the Food and Drug Administration, postmarketing safety concerns have been raised by the vitreoretinal community. The American Society of Retina Specialists Therapeutic Surveillance Committee was commissioned to monitor postmarketing drug-related and device-related adverse events. The purpose of this report is to analyze the postmarketing safety experience in the context of available premarketing safety data. METHODS: Periodic aggregate safety reports consisting of premarketing, or clinical trial, data (n = 999 injections) and postmarketing reports through July 16, 2013 (n = 4,387 injections), were retrospectively analyzed by the TSC. The aggregate data were analyzed to classify adverse events, and the postmarketing safety data for each event type were compared with the premarketing data. RESULTS: Eight categories of adverse events were identified. Acute reduction in visual acuity attributable to either worsening of macular pathology or development of subretinal fluid, electroretinogram changes, dyschromatopsia, retinal tears and detachments, lens subluxation or phacodonesis, impaired pupillary reflex, and retinal vessel findings were reported in both the premarketing and postmarketing experiences. Ellipsoid zone (inner segment/outer segment) findings were only reported in the postmarketing experience. Rates of postmarketing reports were lower than in the premarketing data. Adverse events were generally transient, and characteristics of these adverse events were generally similar between the premarketing and postmarketing experience. CONCLUSION: Postmarket analyses are limited by significant underreporting, and in the case of ocriplasmin as a first in-class drug, they may not have captured safety events that have only more recently been identified. Nonetheless, postmarket analyses can identify the scope of potential safety events based on real-world experiences. Ocriplasmin administration should be guided by an appropriate and informed risk-benefit discussion with the patient. Ongoing active postmarket surveillance by all practitioners will continue to be critical to better understand this safety profile.