[Perioperative visual loss : Rare, unknown, relevant?] / Perioperativer Visusverlust : Selten, unbekannt, relevant?

Perioperative visual loss (POVL) is a rare but severe complication following non-ophthalmological surgery under general anesthesia. A POVL can be caused by lesions in any part of the optical system. The predominant causes include corneal injuries and particularly ischemic damage. The symptoms of POVL substantially vary ranging from reduced vision to complete blindness. The risks involve factors related to the surgery as well as patient-specific factors. In general, the prognosis in cases of mechanical damage is better than for ischemic lesions. The treatment measures depend on the underlying pathomechanism and due to the limited evidence only a few treatment options are available. Therefore, preventive measures and meticulous documentation play a crucial role.

Evaluating the accuracy of the Ophthalmologist Robot for multiple blindness-causing eye diseases: a multicentre, prospective study protocol.

INTRODUCTION: Early eye screening and treatment can reduce the incidence of blindness by detecting and addressing eye diseases at an early stage. The Ophthalmologist Robot is an automated device that can simultaneously capture ocular surface and fundus images without the need for ophthalmologists, making it highly suitable for primary application. However, the accuracy of the device's screening capabilities requires further validation. This study aims to evaluate and compare the screening accuracies of ophthalmologists and deep learning models using images captured by the Ophthalmologist Robot, in order to identify a screening method that is both highly accurate and cost-effective. Our findings may provide valuable insights into the potential applications of remote eye screening. METHODS AND ANALYSIS: This is a multicentre, prospective study that will recruit approximately 1578 participants from 3 hospitals. All participants will undergo ocular surface and fundus images taken by the Ophthalmologist Robot. Additionally, 695 participants will have their ocular surface imaged with a slit lamp. Relevant information from outpatient medical records will be collected. The primary objective is to evaluate the accuracy of ophthalmologists' screening for multiple blindness-causing eye diseases using device images through receiver operating characteristic curve analysis. The targeted diseases include keratitis, corneal scar, cataract, diabetic retinopathy, age-related macular degeneration, glaucomatous optic neuropathy and pathological myopia. The secondary objective is to assess the accuracy of deep learning models in disease screening. Furthermore, the study aims to compare the consistency between the Ophthalmologist Robot and the slit lamp in screening for keratitis and corneal scar using the Kappa test. Additionally, the cost-effectiveness of three eye screening methods, based on non-telemedicine screening, ophthalmologist-telemedicine screening and artificial intelligence-telemedicine screening, will be assessed by constructing Markov models. ETHICS AND DISSEMINATION: The study has obtained approval from the ethics committee of the Ophthalmology and Optometry Hospital of Wenzhou Medical University (reference: 2023-026 K-21-01). This work will be disseminated by peer-review publications, abstract presentations at national and international conferences and data sharing with other researchers. TRIAL REGISTRATION NUMBER: ChiCTR2300070082.

Auditory Spatial Bisection of Blind and Normally Sighted Individuals in Free Field and Virtual Acoustics.

Sound localization is an important ability in everyday life. This study investigates the influence of vision and presentation mode on auditory spatial bisection performance. Subjects were asked to identify the smaller perceived distance between three consecutive stimuli that were either presented via loudspeakers (free field) or via headphones after convolution with generic head-related impulse responses (binaural reproduction). Thirteen azimuthal sound incidence angles on a circular arc segment of ±24° at a radius of 3 m were included in three regions of space (front, rear, and laterally left). Twenty normally sighted (measured both sighted and blindfolded) and eight blind persons participated. Results showed no significant differences with respect to visual condition, but strong effects of sound direction and presentation mode. Psychometric functions were steepest in frontal space and indicated median spatial bisection thresholds of 11°-14°. Thresholds increased significantly in rear (11°-17°) and laterally left (20°-28°) space in free field. Individual pinna and torso cues, as available only in free field presentation, improved the performance of all participants compared to binaural reproduction. Especially in rear space, auditory spatial bisection thresholds were three to four times higher (i.e., poorer) using binaural reproduction than in free field. The results underline the importance of individual auditory spatial cues for spatial bisection, irrespective of access to vision, which indicates that vision may not be strictly necessary to calibrate allocentric spatial hearing.

A SYSTEMATIC LITERATURE REVIEW OF DISEASE PROGRESSION REPORTED IN RPGR -ASSOCIATED X-LINKED RETINITIS PIGMENTOSA.

PURPOSE: Retinitis pigmentosa GTPase regulator-associated X-linked retinitis pigmentosa ( RPGR -associated XLRP) is a rare and severe form of retinitis pigmentosa, resulting in progressive visual impairment; however, disease progression data are limited. A systematic literature review was conducted to assess available data on disease progression in RPGR -associated XLRP. METHODS: PubMed, Embase, and select congress abstracts were evaluated through June 2022. Eligible studies included results specific to RPGR -associated XLRP or populations with ≥80% of patients with retinitis pigmentosa carrying disease-causing RPGR variants. End points of interest included visual acuity, visual field, ellipsoid zone width, progression to blindness, and patient-reported outcomes. RESULTS: Fourteen studies met ≥1 end point of interest. Progressive declines in visual acuity, visual field, and ellipsoid zone width were reported across studies. Nearly all publications reported annual declines in visual acuity (3.5%-8.2%). Annual visual field declines ranged from 4.2% to 13.3%. Changes in retinal structure were also observed (ellipsoid zone width changes: -177 to -830 µ m/year). Most studies measured blindness using visual acuity; visual field-based definitions resulted in blindness by age ∼25 years. Patient-reported outcome data were limited. CONCLUSION: Published evidence shows that patients with RPGR -associated XLRP experience progressive decline in visual acuity, visual field, and ellipsoid zone width, eventually resulting in blindness. Additional longitudinal data with standardized end points and expanded collection of patient-reported outcomes are needed to assess visual decline in RPGR -associated XLRP.

Novel mutation in the NDP gene associated with Norrie disease in a Chinese pedigree.

PURPOSE: Norrie disease (ND) is a rare X-linked recessive disorder characteristic of early childhood blindness. While several mutations in the NDP gene have been reported as causative for ND, the genetic etiology remains unknown for many patients. This study aims to describe a novel mutation and explore the clinical manifestations in a Chinese family with two affected males. METHODS: Exome sequencing (ES) was employed to identify the causative gene in a four-generation pedigree. Sanger sequencing was subsequently utilized to validate the mutation detected by ES in additional family members. Ophthalmologic examination and diagnostic imaging relevant to ND were conducted. RESULTS: The proband (IV:2), an 8-month-old male infant, presented with binocular retinal detachment. DNA sequencing revealed a novel heterozygous missense mutation (c.174G>C) within the NDP gene in the proband. This mutation affected highly conserved residues and was predicted to disrupt the normal protein structure. Furthermore, the variant co-segregated with the disease phenotypes within the family. CONCLUSIONS: Our findings identified a novel missense mutation in the NDP gene associated with Norrie disease in China, expanding the mutation spectrum associated with ND. This discovery holds diagnostic, prognostic, and genetic counseling implications for affected individuals.

Case report: GCA like picture-preceding inaugural MOGAD presentation: A patient with a sudden-onset uniocular blindness.

RATIONALE: Myelin oligodendrocyte glycoprotein antibody-associated disorders (MOGAD) represents a demyelinating neurological syndrome characterized by the presence of serum IgG antibodies directed against myelin oligodendrocyte glycoprotein (MOG-IgG). Concurrently, giant cell arteritis (GCA) constitutes a systemic autoimmune vasculitis. PATIENT CONCERNS: In this case, we describe an elderly female patient who presented with the sudden onset of a severe headache, unilateral blindness, and clinical manifestations resembling those of GCA. DIAGNOSIS: Upon conducting a comprehensive analysis of serum antibodies, the diagnosis of MOGAD was established due to the presence of detectable serum MOG-IgG. INTERVENTIONS: Subsequently, the patient was administered intravenous methylprednisolone therapy, commencing 27 days after the initial onset of symptoms. OUTCOMES: It is noteworthy that patients afflicted by MOGAD typically manifest severe visual impairment, which, in many instances, exhibits significant improvement following immunotherapeutic interventions. However, this particular patient did not experience any amelioration in visual function despite glucocorticoid therapy. LESSONS: This unique case illustrates that the clinical presentation resembling GCA may precede the inaugural manifestation of MOGAD. This suggests the possibility of immune-mediated arterial involvement. The significance of glucocorticoid therapy in the context of immune-related diseases warrants further scrutiny, particularly in cases where MOG-IgG screening should be promptly considered.

Acute bilateral blindness due to diffuse outer retinopathy following clear lens exchange: a case report.

BACKGROUND: As the trend of refractive lens exchange for presbyopia continues to grow, our case report shows the first occurrence of an acute bilateral outer retinopathy following uncomplicated sequential clear lens extraction in an otherwise healthy individual. CASE PRESENTATION: A 54-year-old male without significant medical history benefited from a sequential bilateral lens exchange for presbyopia. He then experienced a rapid vision loss in both eyes, accompanied by photopsias and myodesopsias, with symptoms appearing respectively 4 and 3 weeks after the surgeries. Multimodal imaging revealed a fulminant outer retinopathy, leading to a total loss of light perception within a few days. Immediate intravenous corticosteroid therapy was administered, permitting to recover a small area of central visual function in both eyes, enabling shape and color distinction. The primary diagnostic hypothesis is a presumed autoimmune retinopathy, triggered by the cataract extraction, while an alternative diagnosis could be a toxic reaction secondary to the use of intracameral cefuroxime and lidocaine during the surgery. CONCLUSION: In this report, the authors describe the first recorded instance of outer retinopathy following cataract surgery. This occurrence raises the possibility of auto-immunization leading to retinal atrophy and vision loss as a potential outcome after undergoing cataract surgery.

Methods for a population-based Comprehensive Eye care Workload Assessment (CEWA) study in Southern India.

Eye care programs, in developing countries, are often planned using the prevalence of blindness and visual impairment, often estimated from Rapid Assessment of Avoidable Blindness (RAAB) surveys. A limitation of this planning approach is that it ignores the annual overall eye care requirements for a given population. Moreover, targets set are arbitrary, often influenced by capacity rather than need. To address this lacunae, we implemented a novel study design to estimate the annual need for comprehensive eye care in a 1.2 million populations. We conducted a population-based longitudinal study in Theni district, Tamil Nadu, India. All permanent residents of all ages were included. We conducted the study in three phases, (i) household-level enumeration and enrollment, (ii) basic eye examination (BEE) at household one-year post-enrollment, and (iii) assessment of eye care utilization and full eye examination (FEE) at central locations. All people aged 40 years and above were invited to the FEE. Those aged <40 years were invited to the FEE if indicated. In the main study, we enrolled 24,327 subjects (58% aged below 40 years and 42% aged 40 years and above). Of those less than 40 years, 72% completed the BEE, of whom 20% were referred for FEE at central location. Of the people aged ≥40 years, 70% underwent FEE. Our study design provides insights for appropriate long-term public health intervention planning, resource allocation, effective service delivery, and designing of eye care services for resource-limited settings.

Prevalence and causes of visual impairment in Dongaria indigenous (tribal) community. Tribal Odisha eye disease study # 12.

Purpose: To document the spectrum and magnitude of eye disorders and visual impairment in the Dongaria-a Particularly Vulnerable Tribal Group in the Rayagada district of Odisha, India. Methods: A door-to-door screening protocol included a record of basic health parameters, visual acuity for distance, and near and flashlight examination of the eyes. Spectacles were dispensed to those who improved; those who failed the screening were referred to fixed (primary and secondary) eye care centers. Results: We examined 89% (n = 9872/11,085) of people who consented for screening. The mean age was 25.5 ± 18.8 years; 55% (n = 5391) were female; 13.8% (n = 1361) were under-five children, and 39% (n = 3884) were 6 to 16 years. 86% (n = 8515) were illiterate. 12.4% (n = 1224) were visually impaired, of which 9.9% had early moderate VI, and 2.5% had severe VI and blindness. Uncorrected refractive error was detected in 7.5% (n = 744) and cataracts in 7.6% (n = 754); among the adults, 41.5% (n = 924/2227) had presbyopia. In children, 20% (n = 790) had vitamin A deficiency, 17% (n = 234) had global acute malnutrition, and 18% (n = 244) were stunted for their age. Almost two-thirds (62%, n = 6144) confirmed habitual intake of alcohol, and 4% (n = 389) of adults had essential hypertension. Following the screening, 43.5% (n = 837) of referred patients reported to the fixed centers, and 55% (134/243) of people advised underwent cataract surgery. Spectacles were dispensed to 1496 individuals. Conclusion: Visual impairment and malnutrition are high in Dongaria indigenous community. Permanent health facilities and advocacy would improve this community's health and health-seeking behavior.

RETINITIS PIGMENTOSA ASSOCIATED WITH THE EYS C2139Y VARIANT : An Important Cause of Blindness in East Asian Populations.

PURPOSE: The study aimed to describe the phenotypic features of retinitis pigmentosa (RP) associated with the previously described EYS C2139Y variant in Singaporeans and establish the importance of this variant as a prevalent cause of RP among East Asians. METHODS: A clinical phenotyping and exome-sequencing study was conducted on consecutive patients with nonsyndromic RP. Epidemiological analysis was performed using Singaporean and global population-based genetic data. RESULTS: A study of 150 consecutive unrelated individuals with nonsyndromic RP found that 87 (58%) of cases had plausible genotypes. A previously described missense variant in the EYS gene, 6416G>A (C2139Y), occurred heterozygously or homozygously in 17 of 150 families (11.3%), all with autosomal recessive RP. Symptom onset in EYS C2139Y-related RP ranged from 6 to 45 years, with visual acuity ranging from 20/20 at 21 years to no light perception by 48 years. C2139Y-related RP had typical findings, including sectoral RP in cases with EYS E2703X in trans . The median age at presentation was 45 years and visual fields declined to less than 20° (Goldmann V4e isopter) by age 65 years. Intereye correlation for visual acuity, fields, and ellipsoid band width was high (r 2 = 0.77-0.95). Carrier prevalence was 0.66% (allele frequency of 0.33%) in Singaporean Chinese and 0.34% in East Asians, suggesting a global disease burden exceeding 10,000 individuals. CONCLUSION: The EYS C2139Y variant is common in Singaporean RP patients and other ethnic Chinese populations. Targeted molecular therapy for this single variant could potentially treat a significant proportion of RP cases worldwide.

Using Object Detection Technology to Identify Defects in Clothing for Blind People.

Blind people often encounter challenges in managing their clothing, specifically in identifying defects such as stains or holes. With the progress of the computer vision field, it is crucial to minimize these limitations as much as possible to assist blind people with selecting appropriate clothing. Therefore, the objective of this paper is to use object detection technology to categorize and detect stains on garments. The defect detection system proposed in this study relies on the You Only Look Once (YOLO) architecture, which is a single-stage object detector that is well-suited for automated inspection tasks. The authors collected a dataset of clothing with defects and used it to train and evaluate the proposed system. The methodology used for the optimization of the defect detection system was based on three main components: (i) increasing the dataset with new defects, illumination conditions, and backgrounds, (ii) introducing data augmentation, and (iii) introducing defect classification. The authors compared and evaluated three different YOLOv5 models. The results of this study demonstrate that the proposed approach is effective and suitable for different challenging defect detection conditions, showing high average precision (AP) values, and paving the way for a mobile application to be accessible for the blind community.

Validity and Reliability of Vis-Screen Application: A Smartphone-Based Distance Vision Testing for Visual Impairment and Blindness Vision Screening.

Background and Objectives: The health-related mobile applications (app) might assist in promoting inclusive health and tele-treatment, especially for the less severe diseases. In this paper, a study had been done to determine the app's reliability in terms of raters and the app's agreement with the Snellen chart. Materials and Methods: A cross-sectional sectional study was conducted between November 2019 and September 2020. Participants were selected via purposive sampling from selected communities in Terengganu state. All participants underwent vision testing with the Vis-Screen app and Snellen chart for validity and reliability accordingly. Results: A total of 408 participants were involved, with a mean age of 29.3. The sensitivity of the presenting vision of the right eye (PVR) ranged from 55.6% to 88.4%, with specificity between 94.7% to 99.3%, while the positive and negative predictive values were between 57.9% and 81.7% and 96.8% and 99.0%, respectively. The positive likelihood ratios ranged between 16.73 and 73.89, whereas the negative likelihood ratios ranged from 0.12 to 0.45. The area under the receiver operating characteristic curve (AUC) for all cut-off points ranged between 0.93 and 0.97, and the optimum cut-off point was at 6/12. The kappa values for intra-rater and inter-rater were 0.85 and 0.75, respectively, while the app's reliability with the Snellen chart was 0.61. Conclusions: Vis-Screen was concluded to be valid and reliable for use as a screening tool for detecting individuals with visual impairment and blindness in the community. A valid and reliable portable vision screener like Vis-Screen will help expand the eye care feasibility while providing similar accuracy as the conventional charts in clinical practices.

The Effect of Blindness on Biological Rhythms and the Consequences of Circadian Rhythm Disorder.

Various physiological systems and behaviors such as the sleep-wake cycle, vigilance, body temperature, and the secretion of certain hormones are governed by a 24-hour cycle called the circadian system. While there are many external stimuli involved the regulation of circadian rhythm, the most powerful environmental stimulus is the daily light-dark cycle. Blind individuals with no light perception develop circadian desynchrony. This leads to non-24-hour sleep-wake rhythm disorder, which is associated with sleep-wake disorders, as well as mood disorders and loss of appetite and gastrointestinal disturbances due to disrupted circadian hormone regulation. As the diagnosis is often delayed because of under-recognition in clinical practice, patients must cope with varying degrees of social and academic dysfunction. Most blind individuals report that non-24-hour sleep-wake rhythm disorder affects them more than blindness. In the treatment of totally blind patients suffering from non-24-hour sleep-wake rhythm disorder, the first-line management is behavioral approaches. Drug therapy includes melatonin and the melatonin agonist tasimelteon. Diagnosing blind individuals' sleep disorders is also relevant to treatment because they can be improved with the use of melatonin and its analogues or by phototherapy if they have residual vision. Therefore, assessing sleep problems and planning treatment accordingly for individuals presenting with blindness is an important issue for ophthalmologists to keep in mind.