Color Vision Testing Research Articles

Efficacy of ChromaGen lenses in enhancing color perception in color vision deficiency: a critical evaluation

Aims: Despite advancements in color vision correction, evidence supporting the efficacy of ChromaGen haploscopic filter systems in improving color perception remains limited. This study primarily investigates the performance of ChromaGen lenses (CL). Methods: The study included 27 volunteers diagnosed with color vision deficiency (CVD). An anomaloscope was used to detect color vision defects. Participants underwent color vision tests (Ishihara and Panel D15) both with and without CL. The results were statistically analyzed. Results: All participants were male, aged 21 to 57. Among them, 12 (44%) had protan defect (10 protanopes, 2 protanomalies) and 15 (56%) had deutan defect (12 deuteranopes, 3 deuteranomalies). Without CL, protan defect participants read 2.0±1.0 pages on the Ishihara test, while deutan defect participants read 3.0±1.9 pages. With CL, protan defect participants read 4.5±2.2 pages and deutan defect participants read 14.2±0.9 pages, showing statistically significant improvement (p<0.05). The difference between protan and deutan groups was also statistically significant (p<0.05). In the Panel D15 test, without the use of CL 81% of individuals with protanopia and deuteranopia made significant errors, whereas participants with protanomaly and deuteranomaly performed well. No significant improvement was noted with CL in the Panel D15 results. Twenty-three participants preferred magenta and four preferred pink CL. Fifteen participants expressed interest in using CL solely to pass the Ishihara test. Conclusion: This study concludes that commercially available ChromaGen filters do not provide clinically significant evidence of improved subjective color perception. Therefore, recommending these devices to the CVD population for color perception may not be highly beneficial. However ChromaGen lenses may be used by some CVD patients to pass the Ishihara test.

Evaluation of novel tablet-based color vision tests

Evaluation of novel tablet-based color vision tests

Accuracy of a commonly used mobile ophthalmology application's vision assessment tools in measuring five vision assessment parameters.

The use of mobile ophthalmology applications (MOA) is increasing, but many of these tools have not been validated. This study was performed to assess the accuracy of a popular MOA, Eye Handbook, in measuring five commonly-tested vision assessment parameters (distance visual acuity (DVA), near visual acuity (NVA), colour vision testing (CVT), contrast sensitivity (CS), and pupillary distance (PD)) was compared with traditional vision assessment methods (TVAM) [i.e. Snellen chart, Rosenbaum near card, Ishihara, Pelli Robson test, etc.] performed in the eye clinic setting. Prospective crossover clinical trial of 129 patients meeting inclusion criteria. Participants averaged significantly better DVA (p = 0.0008), NVA (p < 0.0001), and CVT (p = 0.0105) in the MOA than the TVAM, but all three MOA assessments were predictive of the TVAM values. CS was significantly better with the MOA (p < 0.0001). Linear regression and Spearman correlation tests were applied to assess the effect of CS on NVA, which showed no clear relationship between the difference in NVA and the difference in CS. PD using the two methods was in agreement with no significant difference (p = 0.2889). The studied MOA offers an effective means of measuring four common vision parameters: DVA, NVA, CVT, and PD. The MOA can potentially be used by eye care providers, health care providers, and patients, both as a screening tool with correction factor and to monitor ocular pathologies. Atypical MOA measurements should prompt testing in the clinic with formal TVAMs.

Impact of blur on clinical and occupational colour vision test results.

To evaluate whether colour vision normal (CVN) adults pass two Fletcher-Evans (CAM) lantern tests and to investigate the impact of imposed blur on Ishihara, CAM lantern and computerised colour discrimination test (colour assessment and diagnosis test [CAD] and Cambridge colour test [CCT]) results. In a pilot experiment, 20 (16 CVN and 4 colour vision deficient [CVD]) participants with normal VA were tested with the CAM lantern. In the main experiment, the impact of imposed dioptric blur (up to +8.00 D) on visual acuity and the Ishihara test, CAM lantern, CAD and CCT was assessed for 15 CVN participants. CVN participants can fail the CAM lantern, with specificity of 81.25% (aviation mode) and 75% (clinical mode), despite following the test requirements of participants having at least 0.18 logMAR (6/9) in the better eye. With blur, test accuracy was affected. As expected, significant detrimental effects of blur on test results were found for logMAR VA and CAM lantern (aviation) with +1.00 D or higher. Ishihara, CAD and CCT results were not detrimentally affected until +8.00 D. Yellow-blue discrimination was more affected by blur for the CAD than the CCT, which was not explained by the different colour spaces used or vectors tested. False-positive findings on lantern colour vision tests with small apertures are likely to be increased in patients with blur due to uncorrected refractive error or ocular and visual pathway disease. Other colour vision tests with larger stimuli are more robust to blur.

Application of the international criteria for optic neuritis in the Acute Optic Neuritis Network.

The first international consensus criteria for optic neuritis (ICON) were published in 2022. We applied these criteria to a prospective, global observational study of acute optic neuritis (ON). We included 160 patients with a first-ever acute ON suggestive of a demyelinating CNS disease from the Acute Optic Neuritis Network (ACON). We applied the 2022 ICON to all participants and subsequently adjusted the ICON by replacing a missing relative afferent pupillary defect (RAPD) or dyschromatopsia if magnetic resonance imaging pathology of the optical nerve plus optical coherence tomography abnormalities or certain biomarkers are present. According to the 2022 ICON, 80 (50%) patients were classified as definite ON, 12 (7%) patients were classified as possible ON, and 68 (43%) as not ON (NON). The main reasons for classification as NON were absent RAPD (52 patients, 76%) or dyschromatopsia (49 patients, 72%). Distribution of underlying ON etiologies was as follows: 78 (49%) patients had a single isolated ON, 41 (26%) patients were diagnosed with multiple sclerosis, 25 (16%) patients with myelin oligodendrocyte glycoprotein antibody-associated disease, and 15 (9%) with neuromyelitis optica spectrum disorder. The application of the adjusted ON criteria yielded a higher proportion of patients classified as ON (126 patients, 79%). According to the 2022 ICON, almost half of the included patients in ACON did not fulfill the requirements for classification of definite or possible ON, particularly due to missing RAPD and dyschromatopsia. Thorough RAPD examination and formal color vision testing are critical to the application of the 2022 ICON.

Visual recovery after oral high-dose methylprednisolone in acute inflammatory optic neuropathy.

High doses of venous corticosteroids are currently the only validated treatment for the management of optic neuritis (ON). The objective is to assess the changes in visual function parameters after oral high-dose methylprednisolone in patients with ON. A retrospective analysis of patients with acute ON was performed. Patients received 1 g per day of oral methylprednisolone for 3 to 5 days. Visual function was measured using the ETDRS test for visual acuity, 30-2 automated visual field test, contrast sensitivity test, and color vision test before treatment, 4 days, 2 weeks, 1 month and 3 months, and 6 months following treatment. To assess anatomical changes, optical coherence tomography of the ganglion cells was performed at various timepoints. Between September 2014 and September 2016, a total of 29 patients were included in the study. More than 80% of patients had recovered normal visual acuity after 3 and 6months. This recovery of all parameters of visual function was observed as early as 4days but occurred predominantly within 15days after the initiation of treatment. We observed a thinning of the ganglion cell layer during the follow-up, which mainly occurs within one month. The P100 wave of visually evoked potentials was discernible in all patients at 6months. During the 6years of follow-up, 2 patients had experienced a relapse of ON. No serious adverse effects were observed. This study demonstrated a rapid recovery of all visual function parameters after oral high-dose methylprednisolone ON with no serious adverse effects.

Triad of benign fleck retina with keratoconus with myopia – A rare case report

A 24-year-old male presented with a complaint of frequent change of glasses in both eyes. His best corrected visual acuity was 20/20 OD and 20/30 OS with a correction of − 6 DS/−3.75 DC @ 50° and − 4.5 DS/−3.25 DC @140°, respectively. Anterior-segment examination revealed a thin steep cornea with normal intraocular pressure in both eyes. Dilated fundus examination showed multiple yellow-white flecked lesions involving the entire fundus but sparing the fovea with pigmented lattices in both eyes. The flecks appeared as localized elevation at the RPE-Bruch’s membrane complex on optical coherence tomography. Corneal topography was suggestive of keratoconus. Examination of his family members did not reveal any abnormalities. Electroretinogram (ERG), electrooculogram, and color vision testing in both eyes were normal. The diagnosis of benign fleck retina with myopia with keratoconus was made. ERG helps distinguish benign familial fleck retina from other flecked retina syndromes to educate the patient about their visual prognosis. To the best of our knowledge, no such case has been reported in Indian literature till now.

Test time affects Farnsworth D15 outcomes in practiced, but not unpracticed, subjects with color vision deficiency.

Imposing a time limit on the Farnsworth D15 test may prevent patients from compromising the test. This study aimed to investigate the effect of test time on the Farnsworth D15 color vision test in unpracticed and practiced subjects and determine an optimal test time. Twenty-one subjects (mean/standard deviation age, 33.1/9.3 years) with a range of congenital color vision deficiency participated in the study. Pseudoisochromatic plate screening, Farnsworth D15, and anomaloscope testing were performed for classification purposes. At each of 2 visits, 10 trials of the Farnsworth D15 were performed with a range in test times from 30 seconds to 10 minutes. Between visits, subjects practiced the test. Major crossovers were used as the outcome measure. A repeated-measures analysis of variance compared the scores across trials. Post hoc Dunnett's testing analyzed the pairwise data. Although no significant difference in the mean number of major crossovers was found across the 10 trials for the first visit ( F (9, 180) = 1.30, p=0.24), a significant difference was found for the second visit ( F (9, 180) = 4.77, p<0.001). The range of mean number of major crossovers for the second visit was 1.71 to 5.1, with the 30-second trial resulting in the largest number of major crossovers and the longest trial resulting in the smallest number of major crossovers. Analysis showed that a 2-minute time limit resulted in a Farnsworth D15 outcome that would be expected based on the anomaloscope for a majority of subjects. In this study, test time was found to affect performance in practiced subjects but not in unpracticed subjects. Based on this study, we recommend enforcing a time limit of 2 minutes to discourage those who try to pass the Farnsworth D15 through practice. Additional measures, such as recording patient behavior, can also be taken.

Prevalence and Causes of Visual Impairment and Blindness Among Students of Blind Schools of Bihar, India

Aim: Visual impairment and blindness are serious public health issues, especially in developing countories, like India. Data on causes of childhood visual impairment and blindness in Bihar are limited. The aim of this study was to determine the leading causes of visual impairment and blindness in blind schools of Bihar Study design: A cross sectional study was done in seven blind schools of Bihar Methods: Seven blind schools were visited after taking permission from principal. Written informed consent from parents was taken. Detailed ocular and systemic examination was done for all 218 students. Comprehensive eye examinations were performed, including distance visual acuity, anterior and posterior segment examinations, refraction, color vision, and visual field testing. Anatomical and etiological categorization of causes of visual impairment/Blindness was done. Results: A total 218 students were examined. 90.82% of students were blind and 9.17% severely visually impaired. Major anatomical causes of visual impairment and blindness were Microphthalmos (24.31%), Anophthalmos (23.39%), Optic Atrophy (9.63%) and Corneal Scar (7.80%). Etiologically the most common cause was of unknown etiology followed by postnatal factors. Preventable or treatable causes, such as glaucoma, cataract, and refractive errors, represented 22.48% of the cases Conclusion: Blindness and Low vision due to congenital ocular conditions affecting whole globe was the most common cause, further population based studies are needed to know the exact magnitude of problem and to make strategies to decrease the incidence. There is a need to strengthen current primary preventions strategies while tertiary referral centers, Low Vision setups, awareness program regarding Low Vision, special education, rehabilitation, ocular disability benefits and many more things need to be set up in the different health zones of the state to manage childhood preventable and avoidable blindness.

Effect of Blue Light Filter Intraocular Lens (IOL) on Colour Vision.

Purpose The objective of this study is to knowthe effect of blue light filter (BF) intraocular lenses (IOL) on colour vision of Sudanese patiens as BF IOLs are relatively new in Sudan and its effect on Sudanese patients is not yet studied. Methods This was a descriptive cross-sectional observational study. Data collection was done through interview andpretested structured questionnaire containing three sections: (i) personal data, (ii) past medical and ocular surgical history, and (iii) visual acuity (VA), the anterior and posterior segment exam result, and the D15photopic color vision test result. Results In this study, 206 eyes of 103 patients were enrolled. Of them, 57 (55.3%) were females and 46 (44.7 %) were males. The mean age of the participants was 58.38 years±11.488 (SD). Furthermore, 81 patients (78.64%) achieved normal D15 color vision test results, while 22 patients (21.4%) had abnormal results. There was a significant effect (P=.00) on photopic color vision perception. Finally, the gender-wise performance showed an insignificant difference (P=.933)with 78.3% of the males having normal D15 color vision test and the females having slightly better results with 78.9 %. Conclusions The results suggested that implantation of BF IOLs has a significanteffect on photopic color vision perception.

Analyzing the effect of blue-blocking lenses on color vision tests using the chromaticity coordinate method

SignificanceBlue light with wavelengths of 380–445 nm can harm the retina, leading to the development of blue-blocking lenses (BBLs). Understanding whether BBLs affect color vision test outcomes and color discrimination ability is crucial for people in color-associated jobs. AimThis study aimed to evaluate the effect of BBLs on color vision tests and analyze color discrimination using mathematical models of color spaces. ApproachSix pseudoisochromatic (PIC) tests and two Farnsworth-Munsell (FM) tests were conducted to assess participants’ color vision. Friedman signed rank test was used to compare the outcomes of the Farnsworth-Munsell 100-Hue Tests (FM 100-Hue Tests) between the BBLs and ordinary lenses groups. The CIE color difference formula and a spectral illuminometer were employed to evaluate the color differences with and without BBLs. ResultsAll subjects showed normal outcomes in all PIC tests and Farnsworth-Munsell Dichotomous D-15 Tests (FM D-15 Tests). There were no significant differences between ordinary lenses group and BBLs groups in FM 100-Hue Tests. In the color space, the effect of BBLs on each color light was equivalent to a translation on the CIE 1931 chromaticity diagram with minor distortion. Since BBLs do not disrupt the continuity of the chromaticity diagram, or cause different colors to appear the same, they do not lead to color confusion. However, colors with short wavelengths exhibited more changes in color difference when wearing BBLs. ConclusionsBBLs do not impair the wearer's ability to discriminate colors or perform color vision tests accurately. However, BBLs can cause color differences especially in the recognition of blue hues.

Assessment of visual and blood-related parameters among children with sickle cell anaemia at Murtala Muhammad Specialist Hospital in Kano, Nigeria.

Sickle cell disease (SCD) is a prevalent genetic disease worldwide and particularly in Nigeria. Retinopathy is a known complication of SCD, underscoring the need to assess visual parameters in children. This study aimed to evaluate the visual acuity (VA), color vision (CV), packed cell volume (PCV), and erythrocyte sedimentation rate (ESR) of Sickle cell anemic (SCA) patients attending the Sickle cell counseling unit of Murtala Muhammad Specialist Hospital (MMSH) in Kano. It was a descriptive cross-sectional study consisting of 60 participants, including 30 SCA patients and 30 healthy controls without systemic or ocular diseases, aged between 8 and 14 years. Visual acuity, CV, PCV, and ESR were assessed using Snellen Chart, Ishihara chart, Hematocrit test, and Westergren Method respectively. Data were analyzed using SPSS version 22.0. Statistical significance was set at P &lt; 0.05. Both SCA patients and controls demonstrated limited knowledge about VA, CV, and ESR tests, and a significant percentage had never undergone these tests. SCA patients exhibited mild to moderate visual impairment (VI) in both eyes, while controls had no VI. Abnormally low PCV and ESR values were observed in all SCA patients, whereas controls had normal values. Gender differences were observed in ESR levels, with females showing higher levels. Significant differences were found between controls and SCA patients in terms of VA, ESR, and PCV values. There was a general lack of awareness regarding the importance of VA and CV tests in the community. Visual impairment and abnormal PCV and ESR values were exclusive to the SCA patients, indicating their association with the disease.

Chromatic vision and structural assessment in primary congenital glaucoma

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.

Evaluating the level of visual acuity to minimise false-positives in different colour vision tests

ABSTRACT Clinical relevance Accurate colour vision assessment is important in clinical settings to minimise false-positive errors and enhance the reliability of diagnoses outcomes. Background Colour vision testing is valuable in assessing the visual system, particularly given the high proportion of individuals with poor vision. This study aimed to determine the minimum visual acuity level required to perform a colour-vision test without errors. Methods After fogging the right eyes of 52 healthy participants using plus lenses to 1.60 logMAR, vision was evaluated using Ishihara, Hardy – Rand – Rittler Standard Isochromatic, Waggoner Pseudo-isochromatic, City University, Waggoner Computerised, and Farnsworth D-15 tests. Participants then completed these tests at lower fogging degrees (in 0.1-logMAR intervals). The acuity at which 5% of the tested population was considered abnormal was determined. Results Significant differences were found in the average visual acuity required to perform colour vision tests without errors (p < 0.05). The Waggoner Computerized test required the highest average visual acuity among the tests utilised. The Farnsworth D-15 test yielded the highest logMAR values. No significant differences were observed between the Waggoner Pseudo-isochromatic test and Hardy – Rand – Rittler Standard Isochromatic, Ishihara, and Farnsworth D-15 tests (p > 0.05). Additionally, no significant differences were found between the Ishihara and Hardy – Rand – Rittler tests (p > 0.1) or between the Waggoner Computerized and City University tests (p = 0.11). Colour vision testing maintained an accuracy ≤ 1.0 logMAR with the Ishihara and Hardy – Rand – Rittler tests, 1.1 logMAR with the Waggoner Pseudo-isochromatic and Farnsworth D-15 tests, and 0.9 logMAR with the Waggoner Computerized and City University tests. Conclusions Insights are provided into the visual acuity thresholds required for accurate colour vision testing, which can serve as a basis for future research and provide a reference for clinical practice in this field.

Color discrimination in fixed saturation level of patients with acute traumatic injury.

Traumatic brain injury (TBI) is an important public health concern and that may lead to severe neural sequels, such as color vision deficits. We evaluated the color vision of 10 TBI patients with normal cognitive function using a color discrimination test in a fixed saturation level. We also analyzed computerized tomography scans to identify the local of the brain damages. Four TBI patients that had lesions in brain areas of the ventral visual streams, five TBI patients had lesions inferred in brain areas of the dorsal visual stream, and one TBI patient had lesion in the occipital area. All the patients had cognitive and color vision screened and they had characterized the chromatic discrimination at high and low saturation. All participants had no significant cognitive impairment in the moment of the color vision test. Additionally, they had perfect performance for discrimination of chromatic stimulus at high saturation and similar to controls (n = 37 age-matched participants). Three of four TBI patients with lesions in the ventral brain and one patient with lesion in the occipital area had impairment of the chromatic discrimination at low saturation. All TBI patients with lesions in the dorsal brain had performance similar or slightly worse than the controls. Chromatic discrimination at low saturation was associated to visual damage in the ventral region of the brain and is a potential tool for functional evaluation of brain damage in TBI patients.

Electrodiagnostic Biomarkers in Paraneoplastic Retinopathy.

Paraneoplastic retinopathy (PNR) is a rapid-onset photoreceptor and post-photoreceptor dysfunction triggered by a cross-reaction between antigens expressed by the underlying tumour and retinal proteins. The present study aims to determine the electrodiagnostic biomarkers that support the diagnosis of PNR and evaluate the effect of treatment. A retrospective observational case-controlled study including 25 patients with suspected PNR, of which 11 patients were diagnosed with PNR. The presence of PNR was confirmed based on clinical examination, supported by colour fundus photography, fundus autofluorescence imaging, optical coherence tomography, fluorescein angiography, retinal vessel oximetry, colour test, full-field electroretinogram (ffERG), on-/off ERG, S-cone ERG, and multifocal ERG (mfERG). The relationships between the clinical symptomatology and the effect of therapy were evaluated. All PNR patients (Nr: 11) presented with subjective symptoms of newly reported central vision or visual field deterioration. Posterior segment findings showed a severe patchy-like retinal atrophy, attenuation of the retinal vessels, and a waxy optic disc. Optical coherence tomography revealed a discontinued ISe line, and multiple hyperreflective foci. Retinal vessel oxygen saturation was increased. Multifocal ERG revealed reduced central and paracentral responses and ffERG severely attenuated scotopic-, photopic-, on-/off- and S-cone responses. The colour vision test revealed a tritan-tetartan-weakness. Two of the PNR patients underwent rituximab therapy with no further progression and even recovery of electrodiagnostic responses.In 1 nPNR (non-paraneoplastic retinopathy) patient (total Nr: 14) pseudoxanthoma elasticum-related retinopathy was the reason for impaired vision. In 3 of 13 patients with bronchopulmonary cancer a MEK- and FGFR-inhibitor- drug toxicity was the reason for the visual deterioration. Careful investigation for signs of central and/or peripheral visual field deterioration must be performed in the presence of history of a co-existing malignancy. The possibility of PNR should be taken into account. The electrodiagnostic biomarkers, suggested in this study, may help to promptly recognise PNR and also to evaluate the effect of implemented therapy.

The Effect of Ethambutol Therapy in terms of Visual Evoked Potential, Color Vision Test, and Contrast Sensitivity Test at the Subclinical Level

Abstract&#x0D; Introduction &amp; Objectives : Ethambutol is one of the first-line drugs in the treatment of tuberculosis and known to induce optic neuropathy. However, there are unknown protocols for detecting subclinical level of toxicity. The aim of this study was to assess the difference in amplitude and latency of visual evoked potential (VEP), color vision, and contrast sensitivity in tuberculosis patients before and after taking ethambutol for 1 and 2 months.&#x0D; Methods : This was a prospective observational cohort study of 38 eyes of 19 newly diagnosed patients with category-1 tuberculosis being treated with ethambutol. All patients were given ethambutol for 2 months at a dose of 15 - 20 mg/kg body weight/day. The participants underwent complete eye and visual function examination including pattern-reversal VEP, color vision with Farnsworth Munsell D-15 test, and contrast sensitivity with LEA Low Contrast Flip Chart before and after 1 and 2 months of treatment. Wilcoxon test was employed for data analysis.&#x0D; Results : During the study, no changes in visual acuity was observed. The results showed that the latencies of VEP after 1 month (p = 0.000) and 2 months (p = 0.000) of treatment were significantly delayed. There was a significant difference in contrast sensitivity after 2 months (p = 0.014) of treatment. However, no significant difference was found in color vision and amplitude of VEP.&#x0D; Conclusion : Latency of VEP and contrast sensitivity test could prove useful in detecting subclinical and hence very useful for monitoring patients under ethambutol therapy for ocular toxicity.

Evaluation of colour vision impairment during acute hypobaric hypoxia in aviation medicine: a randomized controlled trial

The digitization of aircraft cockpits places high demands on the colour vision of pilots. The present study investigates colour vision changes upon acute exposure to hypobaric hypoxia. The digital Waggoner Computerized Color Vision Test and the Waggoner D-15 were performed by 54 healthy volunteers in a decompression chamber. Respective altitude levels were sea level, 10,000 or 15,000 ft for exposure periods of 15 and 60 min, respectively. As for 60 min of exposure a significant decrease in colour perception was found between subjects at 15,000 ft as compared to the control group as well as between subjects at 15,000 ft as compared to subjects at 10,000 ft. No significant difference was found in the comparison within the 15,000 ft groups across time points pre-, peri-, and post-exposure. Thus, pilots appear to experience only minor colour vision impairment up to an exposure altitude of 15,000 ft over 60 min of exposure.

Correlation between color vision, visual acuity, contrast sensitivity and photostress recovery in the visually impaired: a cross-sectional study

Background: To investigate the correlation of colour vision, visual acuity, contrast sensitivity, and photostress recovery time test scores in visually impaired patients. Materials and methods: A total of 133 subjects were enroled and 133 eyes were examined. The pathological group consisted of 76 (57.1%) males with an average age of 68.0 (SD=13.2) and 57 (42.9%) females, with an average age of 68.1 (SD=15.2), Mann–Whitney U test was used to evaluate the differences in K-colour tests, HRR, visual acuity, Contrast Sensitivity test and photostress recovery time test between two different groups of severity. Results: Correlations were found among colour vision tests, visual acuity, contrast sensitivity, and photostress recovery time scores in eyes with age-related macular degeneration, with diabetic retinopathy, with optic nerve diseases, and various other retinal diseases (P&lt;0.05). In patients with moderate-visual impairments. Conclusions: The colour vision test scores correlate with the scores of visual acuity, contrast sensitivity, and photostess recovery time test. It may be a useful clinical surrogate for functional vision.

Ocular toxicity of psychotropic medications in a tertiary hospital in Lagos, Nigeria.

Objective: This study aimed to determine the ocular toxicity of the psychotropic drugs used by patients and to proffer suggestions on how to prevent visual impairment or blindness in patients on antipsychotics. Methodology: This was a prospective, hospital-based cross-sectional study. Participants were adult patients between 18 and 70 years, diagnosed with psychosis, and who had been on antipsychotic medications for at least one year. All the recruited participants had an examination of the anterior and posterior segments of the eyes done. Schirmer's test, Tear film Break-up time (TBUT), Central Corneal thickness (CCT), Colour vision test, and Contrast sensitivity test were done. The collected data was analyzed using IBM SPSS 28.0. Results: The study enrolled patients who were mainly females (55.1%). The highest age group of the cases was 29-38 years (29.7%). The examination of the eyes and investigations revealed that 10.2% of the respondents on antipsychotics had color vision deficiency and 25.4% - loss of contrast sensitivity. Lid pigmentation was observed in 20.3% and cataract in 32.2%. Degeneration of the peripheral retina was observed in 4.2% of patients on antipsychotic medication. Schirmer's test showed mild, moderate, and severe dry eyes in 11%,17.8%, and 20.3% of the participants respectively. The test for Central Corneal Thickness (CCT) showed 50.0% of the respondents had a thin cornea and 24.6% had a thick cornea. 17.8% of the surveyed respondents manifested high eye pressure. Discussion: Psychotropics are the gold standard for the treatment of psychotic episodes and disorders. The choice of drug, dosing, and mode of administration depends on the severity of the psychotic disorder. Higher doses of psychotropics were reported to cause toxicity in different organs in the body including the eyes, especially on long-term use and high dosage and this can affect the quality of life of the individual negatively. Conclusion: The earliest and most prominent side effect seen in patients on psychotic medication was dry eyes. There were a few cases of blinding eye diseases like glaucoma, and cataract. For these reasons, ophthalmic assessments should be included as part of the management of psychiatric patients early at the start of antipsychotic treatment. Abbreviations: FGA = First Generation Antipsychotics, SGA = Second Generation Antipsychotics, TCAs = Tricyclic Antidepressants, CCT = Central Corneal Thickness, IOP = Intraocular Pressure, TBUT =Tear film Break-up Time, BIO = Binocular Indirect Ophthalmoscope.