Abnormal Color Vision Research Articles

Characteristics of autosomal dominant WFS1-associated optic neuropathy and its comparability to OPA1-associated autosomal dominant optic atrophy

This study aims to describe the ophthalmic characteristics of autosomal dominant (AD) WFS1-associated optic atrophy (AD WFS1-OA), and to explore phenotypic differences with dominant optic atrophy (DOA) caused by mutations in the OPA1-gene. WFS1-associated diseases, or ‘wolframinopathies’, exhibit a spectrum of ocular and systemic phenotypes, of which the autosomal recessive Wolfram syndrome has been the most extensively studied. AD mutations in WFS1 also cause various phenotypical changes including OA. The most common phenotype in AD WFS1-associated disease, the combination of OA and hearing loss (HL), clinically resembles the ‘plus’ phenotype of DOA. We performed a comprehensive medical record review across tertiary referral centers in the Netherlands and Belgium resulting in 22 patients with heterozygous WFS1 variants. Eighteen (82%) had HL in addition to OA. Diabetes mellitus was found in 7 (32%). Four patients had isolated OA. One patient had an unusual phenotype with anterior chamber abnormalities and malformations of the extremities. Compared to DOA, AD WFS1-OA patients had different color vision abnormalities (red-green vs blue-yellow in DOA), abnormal OPL lamination on macular OCT (absent in DOA), more generalized thinning of the retinal nerve fiber layer, and more reduced and delayed pattern reversal visual evoked potentials.

Ethambutol induced optic neuropathy: A remerging ocular emergency needing strict vigilance and screening

: To investigate the clinical manifestations and incidence of ethambutol induced optic neuropathy (EON) and identify its risk factors.: A cross sectional, hospital based observational study was conducted in 100 patients, who were on anti-tubercular drugs (ATT) and complained of diminution of vision. The following data was collected in every patient regarding age, gender, co-morbid conditions, clinical manifestation of (tuberculosis)TB, duration and dose of ethambutol. Complete ophthalmic examination was conducted in every patient including best corrected visual acuity (BCVA), color vision, relative afferent pupillary defect (RAPD), fundus examination, visual field analysis and OCT RNFL & GCL. Statistical analysis of the data was done and represented suitably using appropriate statistical tests that included Chi Square test for checking associations and T test for comparing quantitative data with the help of SPSS ver. 26.0 software. All p-values reported were two sided and a value less than 0.05 was considered significant. :Out of 100 patients, only 18 patients were diagnosed with EON and calculated incidence was 1.8%. The most common presenting feature of EON was bilateral diminution of vision (89%) followed by abnormal color vision (11%). On examination, RAPD was seen in 40% cases because of asymmetrical optic nerve involvement and disc abnormality was present in 66% cases. The duration and dose of ethambutol medication, advanced age (>65 years), hypertension, chronic smoking and presence of renal dysfunction were shown to be positively correlated with EON development.:At present, there is no effective treatment for EON except supplementation of zinc, copper, methylcobalamine and pyridoxine. Therefore, early detection and discontinuation of ethambutol is only way to prevent permanent loss of vision, as in early stage it is reversible.

Clinical Characteristics and Underlying Pathophysiology in 4 Subtypes of Dysthyroid Optic Neuropathy Patients

Objective: To analyze different subtypes, clinical characteristics, and pathophysiologies of dysthyroid optic neuropathy (DON) based on orbital fat and extraocular muscle (EOM) volume increases on orbital CT images. Methods: The author retrospectively reviewed the medical records of 80 patients (152 eyes) who were diagnosed with DON and treated at Anam, Guro, or Ansan hospitals of the Korea University College of Medicine from February 2006 to December 2023. Clinical features, ophthalmic examination, demographic characteristics, thyroid status, and radiographic findings from computed tomography scans (prevalence of fat or muscle volume increases) were analyzed. Results: Four groups were designated based on EOM volume (MV) and orbital fat volume (FV). Group 1 had no increase in MV or FV (5.3%, 8 eyes), group 2 had increased FV only (8.66%, 13 eyes), group 3 had an increase in MV only (52.6%, 80 eyes), while group 4 had both MV and FV increase (33.6%, 51 eyes). Patients in group 1 were younger and had low diplopia scores than patients in the other groups. Decreases in visual acuity, color vision abnormalities, diplopia score, and apical crowding were less frequent in groups 1 and 2 than groups 3 and 4 (P=0.000). Patients in groups 3 and 4 had significantly more apical crowding and higher diplopia scores and CAS scores than patients in groups 1 and 2 (P=0.000 and 0.013, respectively). The number of patients who underwent decompression surgery was significantly higher in groups 3 and 4 than groups 1 and 2 (P=0.000). Conclusion: Extraocular muscle enlargement occurred in 86% of DON patients and compression of the optic nerve due to enlargement of EOMs at the orbital apex is the main cause of DON. Optic nerve stretch and vascular insufficiency due to increased orbital pressure are other potential mechanisms underlying DON in groups without an increase in FV or MV. Although decreased visual acuity, color vision abnormalities, and diplopia were less frequent in these groups, greater attention should be paid to the timely diagnosis of DON.

Leber hereditary optic neuropathy in Slovenia: quality of life and costs from patient perspective

IntroductionLeber hereditary optic neuropathy (LHON) is the most commonly diagnosed mitochondrial disorder, resulting in colour vision abnormalities and rapid but painless deterioration of central vision. While numerous studies have assessed the impact of LHON on the quality of life (QoL) of LHON patients, the financial impact of the disease remains unexplored. This study attempts to calculate both the direct non-medical costs and the indirect costs associated with productivity losses experienced by people with LHON and their unpaid caregivers in Slovenia, in addition to assessing their QoL. Due to the rarity of the disease, the study involved a small sample size, which is important to note for interpreting the results.MethodsThe analysis was conducted on nine adult participants diagnosed with LHON, representing one-third of the total number of known Slovenian patients with this condition. To thoroughly assess the economic and social impact of LHON, tailored questionnaires were designed to collect information on demographics, socioeconomic status, LHON severity, and associated non-medical and indirect costs.ResultsThe mean age of the study participants was 48.8 years (SD 13.3; n = 9). The annual productivity loss attributable to LHON, taking both absenteeism and relative presenteeism into account, was calculated to be EUR 11,608 per person affected. The mean VFQ-25 score, a measure of vision-related quality of life, for adult LHON patients was 30.4 (SD 12.9).ConclusionThe findings highlight the significant economic and social burden of LHON on patients and their families. Ensuring prompt, accurate diagnosis, access to treatment, financial support, and psychological counselling and services are critical to helping individuals cope with and mitigate the profound challenges of vision loss and living with LHON.

Orbital Involvement as an Initial Presentation of Sinonasal Neuroendocrine Carcinoma

Purpose: To present a case of sinonasal neuroendocrine cancer initially manifesting with orbital involvement.Case summary: A 63-year-old female patient visited a neuro-ophthalmologic clinic due to a 3-week history of decreased visual acuity (VA), color vision abnormalities, and swelling of the upper eyelid in right eye. Best-corrected VA (BCVA) in the right eye was 0.8. Clinical findings included a relative afferent pupillary defect, restricted eye movement in lateral, superior, and medial gaze, and exophthalmos in the right eye. Wide-field fundus photography and optical coherence tomography indicated swelling of right optic disc. Magnetic resonance imaging was performed revealing a mass invading nasal cavity, sinus, and right orbital apex, and compressing the medial rectus, inferior rectus, superior oblique, and optic nerve. An otolaryngological nasal biopsy was conducted and immunohistochemical staining showed positive results for Ki-67, NSE, p16, P-53, and CD56, leading to a diagnosis of small cell neuroendocrine carcinoma with an irreducible tumor stage. Prior to initiation of treatment (concurrent chemoradiotherapy, CCRT), there was rapid worsening of VA and eye movement in the right eye. CCRT commenced alongside high-dose steroid treatment. One month following treatment, the BCVA of the right eye improved and protrusion of the right eye resolved. Six months after starting CCRT, a contrast-enhanced orbital computed tomography scan showed no residual lesion. The BCVA of the right eye stabilized at 0.3 with complete recovery of color vision and eye movement.Conclusions: Neuroendocrine cancer should be considered as a possible diagnosis in cases of rapidly progressing compressive optic neuropathy.

Ocular findings in Jansen metaphyseal chondrodysplasia.

Jansen metaphyseal chondrodysplasia (JMC) is an ultra-rare disorder caused by germline heterozygous PTHR1 variants resulting in constitutive activation of parathyroid hormone type 1 receptor. A description of ocular manifestations of the disease is lacking. Six patients with JMC underwent a detailed ophthalmic evaluation, spectral-domain optical coherence tomography (OCT), visual field testing, and craniofacial CT scans. Five of 6 patients had good visual acuity. All patients had widely spaced eyes; 5/6 had downslanted palpebral fissures. One patient had proptosis, and another had bilateral ptosis. Two patients had incomplete closure of the eyelids (lagophthalmos), one had a history of progressive right facial nerve palsy with profuse epiphora, while the second had advanced optic nerve atrophy with corresponding retinal nerve fiber layer (RNFL) thinning on OCT and significant bilateral optic canal narrowing on CT scan. Additionally, this patient also had central visual field defects and abnormal color vision. A third patient had normal visual acuity, subtle temporal pallor of the optic nerve head, normal average RNFL, but decreased temporal RNFL and retinal ganglion cell layer analysis (GCA) on OCT. GCA was decreased in 4/6 patients indicating a subclinical optic nerve atrophic process. None of the patients had glaucoma or high myopia. These data represent the first comprehensive report of ophthalmic findings in JMC. Patients with JMC have significant eye findings associated with optic canal narrowing due to extensive skull base dysplastic bone overgrowth that appear to be more prevalent and pronounced with age. Progressive optic neuropathy from optic canal narrowing may be a feature of JMC, and OCT GCA can serve as a useful biomarker for progression in the setting of optic canal narrowing. We suggest that patients with JMC should undergo regular ophthalmic examination including color vision, OCT, visual field testing, orbital, and craniofacial imaging.

Ocular toxicity of daily anti-tubercular treatment regimen: A prospective observational study

Context: India carries a significant burden of TB which is the commonest cause of infectious disease-related mortality. Anti-tubercular drugs can cause serious ocular toxic effects. Optical coherence tomography (OCT) can be used as a valuable tool in the quantitative analysis of anti-tubercular treatment (ATT)-induced toxic optic neuropathy. Aims: To study the changes in visual parameters in patients on ATT and to analyze the OCT changes in patients by taking measurements once before initiation of treatment and once during ongoing treatment (between three and six months). Settings and Design: Tertiary care center, Prospective observational study. Methods and Material: A prospective observational study was conducted in 140 eyes of 70 subjects undergoing ATT as per the latest RNTCP guidelines where the following determinants were examined, and the corresponding values were taken once before initiation of treatment and once during ongoing treatment (between three and six months) and results were analyzed. Around 90% of the subjects were examined at the end fourth month. Visual acuity was taken using the Log Mar chart, color vision using Ishihara’s chart, and slit lamp examination and fundus evaluation using a 90 D lens. OCT was done and average nasal, temporal, superior, and inferior quadrant retinal nerve fiber layer (RNFL) measurements were taken. Perimetry was also done; however, findings were not included in this study. Statistical Analysis Used: Frequency and percentage were applied to study the changes in visual parameters in patients on ATT. A paired t-test was applied for numerical variables to analyze the OCT changes in patients undergoing ATT. A P value < 0.05 was considered statistically significant. Results: Despite a near-normal appearance of the fundus on ophthalmoscopy, OCT clearly demonstrated and quantified the loss of retinal nerve fibers. Statistically significant RNFL thinning (P value < 0.001) was noted in the superior, temporal, and inferior quadrants and least in the nasal quadrant (P = 0.005). Significant deterioration in visual acuity was observed following three months of ATT (P = 0.001). Red-green color vision abnormalities were detected in 14 out of 140 eyes (10%). Conclusions: RNFL thickness was reduced on OCT. RNFL thickness quantification and assessment of other visual parameters especially color vision help in the early diagnosis of ocular toxic effects of ATT. Hence, awareness and active screening are imperative in preventing visual impairment and blindness.

Development and validation of a new colour vision screener: A multi‐centre study

Aims/Purpose: The detection of acquired and congenital colour vision deficiency is of importance in the clinic for the early detection of ocular disease and determination of occupational suitability. Conventional methods of colour vision screening often fail to pass all normals and/or correctly identify those with acquired and congenital colour vision deficiency. The Colour Vision Screener (CVS) test [1] was developed to utilize an improved understanding of colour vision mechanisms to overcome the limitations present in conventional colour screening methods. This study aimed to use a robust multi‐centre methodology to fully validate the CVS test.Methods: Over 400 participants, including 124 normal trichromats, 166 deutans and 62 protans, were recruited from 10 international Colour Assessment and Diagnosis (CAD) testing centres. Each participant completed the CVS and the CAD test with calibrated visual displays. The red/green (RG) and yellow/blue (YB) CVS test sensitivity and specificity were established. The RG statistics were compared to the ‘gold standard’ reference for screening for RG congenital colour vision deficiency—the Ishihara pseudoisochromatic plate test.Results: The CVS test correctly identified ~99.1% of normal trichromats. All subjects with congenital RG loss and acquired loss on top of congenital RG deficiency were identified as having abnormal colour vision by the CVS. The Ishihara test, based upon 0 errors on the first 25 plates of the 38‐plate edition, correctly identifies ~80.6% of normal trichromats and 99.5% of subjects with congenital RG loss.Conclusions: Data collected across 10 international CAD centres demonstrate that the CVS can achieve a high sensitivity without sacrificing specificity. This multi‐centre study demonstrates that the CVS is quick, efficient, and easy to use and allows for the rapid and reliable screening of congenital and acquired colour vision deficiencies in large populations.Reference1. Barbur JL, Rodriguez‐Carmona M, Evans BEW. Colour vision assessment‐3. An efficient, two‐step, colour assessment protocol. Colour Research & Application 2021; 46: 33–45. https://doi.org/10.1002/col.22599

Bilateral uveitis, retinal periphlebitis, and optic neuritis associated with non-pineal central nervous system germinoma

Purpose: To report a case of bilateral uveitis, retinal periphlebitis, and optic neuritis associated with a non-pineal central nervous system (CNS) germinoma. Methods: Case report. Results: A 32-year-old male presented with episodes of acute painless visual disturbance in each eye, and was found to have decreased visual acuity, abnormal color vision, an afferent pupillary defect in the left eye, bilateral optic disc edema, perivenous sheathing, and candle-wax dripping exudates. Optical coherence tomography revealed bilateral intraretinal fluid and posterior vitreous hyperreflective opacities. Fluorescein angiography revealed bilateral optic disc leakage without active small vessel leakage. Magnetic resonance imaging of the brain and orbits revealed enhancing periventricular lesions and enhancement of the left optic nerve and bilateral perioptic nerve sheaths, posterior globes, and optic nerve heads. Brain biopsy was consistent with a CNS germinoma. His ocular signs and symptoms improved with chemotherapy for the germinoma. Conclusion: CNS germinomas, including those located outside the pineal region, can be associated with optic neuritis, uveitis, and periphlebitis including characteristic candle-wax dripping exudates. Ocular signs and symptoms typically improve with treatment of the underlying germinoma.

The Prevalence of Congenital Color Vision Abnormality Among Patients Attending a Tertiary Eye Care Center in Southern India.

Background and objective Color vision abnormality is a condition where the faculty to identify one or more primary colors is either defective (anomalous) or absent (anopia). Occupations like armed forces, merchant navy, navigation, and police and fire services require normal color vision. There is a scarcity of data in the literature regarding the prevalence of congenital color vision abnormality in patients in South India. In light of this, the present study aimed to find the prevalence of congenital color vision abnormality in patients attending the Outpatient Department (OPD) at a tertiary eye care center in South India. Materials and methods This was a descriptive cross-sectional study conducted at a tertiary eye care center in South India from December 2014 to December 2016. Patients with a best-corrected visual acuity of 20/20, normal direct and consensual pupillary light reflex, normal anterior segment, and undilated fundus examination were included. Color vision was assessed using Ishihara pseudoisochromatic plates, American Optical Hardy-Rand-Rittler (AO HRR), and then the Farnsworth Munsell D15 arrangement test. All the results were tabulated and statistically analyzed. Statistical significance was calculated using the ANOVA test. Results A total of 371 patients were screened for color vision abnormality; 184 (49.59%) patients were males and 187 (50.40%)were females. Out of 371 patients in the study, 363(98.10%) had normal color vision while eight patients (2.16%) had color vision abnormality. Of the eight patients with color vision abnormalities, six (75%) had abnormal color vision on all three tests and two(25%) had an abnormality on only two tests (Ishihara and AO HRR). Out of 184 males in the study, eight patients (4.34%) had abnormal color vision while none of the 187 females had color vision abnormality; this difference was statistically significant (p=0.03). Conclusions Early diagnosis and providing education and awareness of this condition are necessary as part of guiding young people with regard to their career options and we recommend that all children should undergo color vision screening before entering high school.

Fundus autofluorescence, optical coherence tomography and electroretinography abnormalities in a patient with digoxin retinopathy that resemble those in KCNV2-associated retinopathy.

Digoxin related retinal toxicity causes blurred vision, photophobia, central scotoma, color vision abnormality, and electroretinography (ERG) abnormalities. Here, we report a case with transient abnormalities in vison, in which fundus autofluorescence (FAF), optical coherence tomography (OCT), and ERG findings resembled those in KCNV2 (potassium voltage-gated channel modifier subfamily V member 2)-associated retinopathy. An 89-year-old woman presented with complaints of acute blurred vision, nyctalopia, photophobia, and color vision abnormality. She received digoxin for tachycardia induced by atrial fibrillation for a month. The fundi showed a faint white ring at the fovea, which showed hyperfluorescence in FAF. OCT showed a thickened EZ in the macula. A dark-adapted (DA)-30 ERG showed a reduced and "squaring (trough-flattened)" a-wave, and a delayed, supernormal b-wave, resulting in a high b/a-wave amplitude ratio. The digoxin dose was reduced following an elevation in serum levels. Five weeks later, her visual acuities improved, and abnormal hyperfluorescence on FAF disappeared. After 6months, no visual symptoms were reported. The ellipsoid-zone thickening in OCT improved; however, the b/a-wave amplitude ratio on DA-30 ERG remained high. The b-wave in LA-long-flash ERG was initially reduced, which improved after correction of serum level of digoxin. The patient's clinical findings resembled those of patients with KCNV2-associated retinopathy or temporal hyperkalemia. These disorders appear to have a common pathogenesis, which may be related to abnormal extracellular potassium levels in the retina. The on-bipolar cells seemed to be more affected than the off-bipolar cells in digoxin related retinal toxicity.

Анализ состояния офтальмологического здоровья призывников в Военном комиссариате Ленинского и Свердловского административных округов города Иркутска Иркутской области

The article analyzes the medical examination of 7372 citizens when conscripted for military service in the military commissariat of the Leninsky and Sverdlovsk administrative districts of the city of Irkutsk, Irkutsk region for 2021–2022. In the structure of fitness for military service of persons of military age for 2021 and 2022, according to the articles of the schedule of diseases, article 34 (refraction and accommodation disorders) takes 1st place, article 31 (retinal detachment) takes 2nd place, and 35 (blindness, low vision, color vision abnormalities) takes 3rd place. Every second young man of military age has a violation of refraction and accommodation, in which myopia (myopia) plays a leading role. A combination of ophthalmic nosologies was found in 530 (13.6 %) conscripts. Keywords: ophthalmological health, medical examination, military service, conscript, ophthalmological nosology

Leber Hereditary Optic Neuropathy in a Family of Carriers of MT-ND5 m.13042G>T (A236S) Novel Variant.

A Slovenian three-generation family with 3 individuals with bilateral optic neuropathy and 2 unaffected relatives with a novel homoplasmic missense variant m.13042G > T (A236S) in the ND5 gene is described. A detailed phenotype at initial diagnosis and a follow-up of bilateral optic neuropathy progression is presented for 2 affected individuals. A detailed phenotype analysis with clinical examination in the early and chronic phase with electrophysiology and OCT segmentation is presented. Genotype analysis with full mitochondrial genome sequencing was performed. Two affected male individuals (maternal cousins) had a profound visual loss at an early age (11 and 20 years) with no recovery. The maternal grandmother exhibited bilateral optic atrophy with a history of visual loss at the age 58 years. The visual loss of both affected male individuals was characterized by centrocecal scotoma, abnormal color vision, abnormal PERG N95, and VEP. Later with disease progression, retinal nerve fiber layer thinning was observed on OCT. We observed no other extraocular clinical features. Mitochondrial sequencing identified a homoplasmic novel variant m.13042G > T (A236S) in the MT-ND5 gene, belonging to a haplogroup K1a. Novel homoplasmic variant m.13042G > T (A236S) in the ND5 gene in our family was associated with Leber hereditary optic neuropathy-like phenotype. However, predicting the pathogenicity of a novel ultra-rare missense variant in the mitochondrial ND5 gene is challenging. Genetic counseling should consider genotypic and phenotypic heterogeneity, incomplete penetrance, haplogroup type, and tissue-specific thresholds.

Dysthyroid optic neuropathy: Demographics, risk factors, investigations, and management outcomes.

To analyze the clinical presentations, risk factors, and management outcomes in patients presenting with dysthyroid optic neuropathy (DON). This is a retrospective, single-center study carried out on consecutive patients presenting with DON over a period of 4 years (2013-2016). The VISA classification was used at the first visit and subsequent follow-ups. The diagnosis was based on optic nerve function tests and imaging features. Demographic profiles, clinical features, risk factors, and management outcomes were analyzed. Thirty-seven eyes of 26 patients diagnosed with DON were included in the study. A significant male preponderance was noted (20, 76.92%). Twenty patients (76.9%, P = 0.011) had hyperthyroidism, and 15 (57.69%, P = 0.02) were smokers. Decreased visual acuity was noted in 28 eyes (75.6%). Abnormal color vision and relative afferent pupillary defects were seen in 24 (64.86%) eyes, and visual field defects were seen in 30 (81.01%) eyes. The visual evoked potential (VEP) showed a reduced amplitude in 30 (96.77%, P = 0.001) of 31 eyes and delayed latency in 20 (64.51%, P = 0.0289) eyes. Twenty-six (70.27%) patients were treated with intravenous methyl prednisolone (IVMP) alone, whereas 11 (29.72%) needed surgical decompression. The overall best-corrected visual acuity improved by 0.2 l logMARunits. There was no statistically significant difference in outcome between medically and surgically treated groups. Four patients developed recurrent DON, and all of them were diabetics. Male gender, hyperthyroid state, and smoking are risk factors for developing DON. VEP, apical crowding, and optic nerve compression are sensitive indicators for diagnosing DON. Diabetics may have a more defiant course and are prone to develop recurrent DON.

Large-field color vision in anomalous trichromats based on a trichromatic display

In the actual display scene, the actual field of view (FOV) is often much larger than the 2°, the color response in a large FOV area should be standardized. How to accurately and comprehensively describe the color vision have been a key issue for display manufacturers. This paper proposes a color perception model for people with abnormal color vision and normal color vision under a large FOV. Based on the shift of photopigments, the tristimulus value of anomalous trichromats (AT) in the case of a large FOV is derived. Considering display lightness, the color gamut in the CIELAB uniform color space is used to evaluate the color discrimination ability of color vision deficits. Further, we propose a method for using laser light source to enlarge color discrimination for individuals with AT in a large FOV and recommend optimal wavelength selection. At the same time, the color discrimination capabilities of several CIE standard light sources are compared. Our results show that the model is compatible with the calculations of various light sources, and it intuitively describes the color perception in a large FOV. This will provide a reference for AT's products with the large display screen, and improve the viewing experience of this group of people.

GUCY2D-Related Retinal Dystrophy with Autosomal Dominant Inheritance-A Multicenter Case Series and Review of Reported Data.

To report the clinical phenotype and associated genotype of a European patient cohort with GUCY2D-related autosomal-dominant (AD) cone–/cone–rod dystrophy (COD/CORD), we retrospectively analyzed 25 patients (17 female, range 12–68) with GUCY2D-related AD-COD/CORD from three major academic centers in Europe and reviewed the previously published data of 148 patients (visual acuity (VA), foveal thickness, age of first symptoms, and genetic variant). Considering all the patients, the onset of first symptoms was reported at a median age of 7 years (interquartile range 5–19 years, n = 78), and mainly consisted of reduced VA, photophobia and color vision abnormality. The disease showed a high degree of inter-eye symmetry in terms of VA (n = 165, Spearman’s ρ = 0.85, p < 0.0001) and foveal thickness (Spearman’s ρ = 0.96, n = 38, p < 0.0001). Disease progression was assessed by plotting VA as a function of age (n = 170). A linear best-fit analysis suggested a loss of 0.17 logMAR per decade (p < 0.0001). We analyzed the largest cohort described so far (n = 173), and found that the most common mutations were p.(Arg838Cys) and p.(Arg838His). Furthermore, the majority of patients suffered severe vision loss in adulthood, highlighting a window of opportunity for potential intervention. The emerging patterns revealed by this study may aid in designing prospective natural history studies to further define endpoints for future interventional trials.

Ethambutol Induced Ocular Toxicity in Patients Receiving “Directly Observed Treatment Short-Course” Therapy

Background: To determine the frequency of Ocular toxicity due to Ethambutol in Category-1 patients after receiving DOTS therapy. Methods: Category-1 tuberculosis patients of 15-60 years (both gender) with normal ocular parameters on ophthalmological assessment at time of initiation of DOTS therapy were included in the study. A total of 242 eyes (121 patients) were studied for any change in the vision or occurrence of any other ocular symptom while on the Ethambutol treatment. Each patient was followed up for Ethambutol compliance status at the completion of one month and again at two months of treatment, all the ophthalmological assessments for ocular toxicity were repeated for every selected patient. Category-2 patients with sputum smear positive who have relapsed, who have treatment failure or who are receiving treatment after treatment interruption were excluded from the study. The patient’s information was gathered on a specifically designed proforma. The information on the proforma was filled by the researchers themselves. Results: Out of 121 patients (242 eyes), 64 (52.9%) were males and 57 (47.1%) were females. There was no sign of ocular toxicity after a month period. However, after second month ocular toxicity was developed in 02 (1.65%) of the patients. Besides, decrease in visual acuity, color vision abnormalities, decrease in contrast sensitivity, and optic disc abnormalities were also observed in these 02 patients. Conclusion: There is a possibility of the occurrence of ocular toxicity when the Ethambutol is taken by the tuberculosis patients. Thus, the early identification of ocular symptoms and signs is vital to avoid unnecessary delay in diagnosis and probable irreversible visual loss.

Visual field defects due to optic nerve drusen in Afro-Caribbean patients: A case series of 16 eyes

Optic Nerve Head Drusen (ONHD) are very rare among black patients but may cause more severe visual defects in these patients. The goal of our study was to describe the frequency of visual field defects secondary to OND in Afro-Caribbean patients and study the characteristics of their physical examination, color vision and contrast sensitivity. We carried out a prospective study at the Martinique university medical center on patients of African descent with ONHD diagnosed on fundus examination and B-scan ultrasonography. All patients received a complete neuro-ophthalmological examination. The primary study endpoint was the frequency of visual field defects. Secondary study endpoints were the results of ETDRS visual acuity, Pelli-Robson contrast sensitivity chart, and 15hue color vision test. Sixteen eyes of 10 patients from 11 to 68 years of age were included. Forteen eyes (87%) had exposed ONHD. Eleven eyes (69%) showed a visual field defect: 9 eyes (69%) had an enlarged blind spot, and 9 eyes (69%) had an arcuate scotoma. 3 eyes (19%) had loss of ETDRS visual acuity, and 12 eyes (75%) showed loss of Pelli-Robson contrast sensitivity. Five eyes (31%) had an abnormal color vision test. This is one of the largest case series of ONHD in Black patients. The frequency of visual field defects was high but comparable to that of studies in other ethnic groups. Larger comparative studies are necessary to confirm these results.

A Study of the Spectrum of Ocular Manifestations in Patients with Thalassemia

Background: Thalassemia is a globally prevalent genetic disorder. Patients with thalassemia are prone to develop systemic and ocular adverse effects such as myocardial iron loading, heart failure, decreased visual acuity, color vision abnormalities, contrast sensitivity changes, ocular surface disease, lens opacities, etc. Fundus abnormalities such as retinal pigment epithelium degeneration, arteriovenous (AV) tortuosity, etc. may be seen. Patients with the long-standing disease are at risk of developing ocular adverse effects that demand baseline ophthalmic evaluation and regular monitoring. Context: Need for a regular ophthalmic checkup in patients with thalassemia. Aim: To determine the prevalence of ocular manifestations in patients with thalassemia. Settings and Design: A cross-sectional study was conducted by recruiting patients with thalassemia after obtaining ethical approval from the institute and informed consent from the parents. Materials and Methods: Fifty patients with thalassemia underwent a detailed ophthalmic evaluation, and the findings were recorded. The Statistical Package AQ6 for the Social Sciences software was used for statistical analysis. Results: Ocular involvement was seen in 37 patients (74%). We observed that 20% of the patients had decreased visual acuity, 38% of the patients had mild dry eye disease, and 14% of the patients had AV tortuosity. Conclusion: Ocular changes in patients with thalassemia occur over a long period. Adverse effects such as ocular surface diseases, lens opacities, increased cup disc ratio, retinal pigment epithelium degeneration, etc. may progress and cause visual impairment at a later stage. It is important to create awareness in these patients to prevent long-term side effects and maintain optimum visual health.

Prevalence of hydroxychloroquine retinopathy with long-term use in a cohort of Indian patients with rheumatic diseases

The study aims to estimate the prevalence of hydroxychloroquine (HCQ) retinopathy in a cohort of Indian patients and analyse the associated factors. Adult patients with rheumatological disorders aged ≥ 18years using HCQ for more than 5years and/or having received a cumulative dose > 400g were included. Demographic and clinical data were collected and all underwent ophthalmological tests which included Humphrey automated visual fields (AVF) and spectral domain optical coherence tomography (SD-OCT). The various clinical characteristics of the patients were compared. The study included 110 patients with a mean age of 43.5 ± 10.1years and predominantly females. Eleven patients (10%) were diagnosed with definite HCQ retinopathy. The mean daily dose of HCQ (mg/kg of real body weight) was significantly different in the groups with and without retinopathy (5.7 ± 0.9 vs 5.1 ± 0.8, p = 0.04). Patients with retinopathy had significantly more colour vision abnormalities (odds of 16.9; confidence interval 4.1-69.1, p = 0.0001) and higher prevalence of both parafoveal and perifoveal thinning (p < 0.0001). Age, gender, duration of HCQ use, cumulative HCQ dose and body mass index were not found to be associated with retinopathy. Four out of 11 patients had abnormalities only on 30-2 protocol for AVF testing, two had abnormalities only on 10-2 protocol, whereas five patients had abnormalities on both protocols. SD-OCT abnormalities were present in all patients with retinopathy. Hydroxychloroquine retinopathy was prevalent in the study cohort and significantly associated with a higher daily dose of HCQ (mg/kg real body weight).