Cause Of Low Vision Research Articles

Exploring the relationship between cathepsin and age-related macular degeneration using Mendelian randomization

PurposeAge-related macular degeneration (AMD) is the leading cause of low vision and even blindness in the elderly population worldwide. However, no studies have been conducted to analyze the causal relationship between the cathepsin family and AMD. The present study aimed to explore and analyze this potential association using Mendelian randomization (MR).MethodsIn this study, AMD was classified into two types: exudative AMD and atrophic AMD. Inverse-variance weighting (IVW) was used as the main analysis method. The association between nine cathepsins and the two classifications of AMD were analyzed using multivariable Mendelian randomization (MVMR). Sensitivity analysis included Cochran’s Q-test and the MR-Egger intercept test.ResultsTwo-sample MR analysis showed that higher levels of cathepsin L2 were associated with a delay in the development of atrophic AMD (IVW: p = 0.017; OR = 0.885; 95% CI = 0.799–0.979). Reverse MR analysis indicated that cathepsin E levels were increased in individuals with atrophic (IVW: p = 0.023; OR = 1.058; 95% CI = 1.007–1.111) and exudative AMD (IVW: p = 0.018; OR = 1.061; 95% CI 1 = 1.010–1.115). MVMR analysis indicated a causal relationship between cathepsin G (IVW: p = 0.025; OR = 1.124; 95% CI = 1.014–1.245), cathepsin O (IVW: p = 0.043, OR = 1.158, 95% CI = 1.004–1.336), and exudative AMD after coordinating for other types of cathepsin.ConclusionThis study demonstrated a potential link between the cathepsin family and the onset of AMD. Elevated serum concentrations of cathepsin L2 may serve as a protective factor for atrophic AMD, while increased levels of serum cathepsin G and O concentrations may promote the development of exudative AMD. Besides, the development of AMD may be associated with elevated serum concentrations of cathepsin E.

Characterization of pediatric low vision and socioeconomic determinants of health at an academic center: a 5-year analysis

PurposeTo investigate the demographics, eye surgeries, and social determinants of health in pediatric patients with low vision in one or both eyes. MethodsThis is a cross-sectional study of children 3-18 years of age examined at an academic eye center from 2014 to 2019. Low vision was present if one eye had a distance best-corrected visual acuity (BCVA) of <20/70. ZIP code was used to estimate patient income via a public third-party database. ResultsOf 47,571 children examined during the study period, 882 had at least one eye with low vision. Of the 882, 88 (10%) had BCVA of <20/400 in at least one eye, and 228 patients (26%) had bilateral low vision. The most common cause of low vision was refractive/strabismic amblyopia (n = 304). The severest forms of vision loss (BCVA<20/200) were predominantly due to retinal dystrophies or detachment (n = 91). Three hundred patients (34%) had undergone at least one ophthalmic surgery—predominantly extraocular muscle procedures in eyes with mild visual loss and vitreoretinal surgeries in those with more severe loss. The severity of vision loss was significantly associated with a higher likelihood and number of surgeries (P < 0.0001). Income and insurance coverage did not have a significant association with BCVA or the likelihood of surgery. ConclusionsRefractive and strabismic amblyopia are the predominant causes of reduced worse-eye vision in children, and retinal diseases commonly caused severe vision loss. The type and number of surgeries correlate with the severity of vision loss. We did not find any association of income and insurance type with studied outcomes.

Changes in Vitreous and Retina in Pathological Myopia

Myopia is the leading cause of visual impairment and its prevalence continues to increase significantly. Pathological myopia affects 1-3% of the general population and is one of the main causes of low vision and blindness worldwide. Myopic vitreopathy associated with pathological myopia essentially represents fibrous vitreous liquefaction, resulting from both hereditary and degenerative processes. In addition, myopic retinopathy, in which axial elongation plays an important role in pathogenesis, has many unique pathologies. In this review, changes in the vitreous and retina in patients with pathological myopia are discussed.

Changes in Lens Structure in Pathological Myopia, Cataract Surgery and Special Situations

Pathological myopia is a major cause of low vision and blindness worldwide. In patients with pathological myopia, there are changes such as thinning of the lens and increase in equatorial diameter. In various population and clinic-based cohort, case-control and cross-sectional studies, it has been reported that myopic patients have a higher risk of posterior subcapsular cataract, cortical and nuclear cataract. It is known that the modern technique of phacoemulsification and intraocular lens implantation is effective in highly myopic eyes and provides significant improvement in visual acuity. However, complications related to phacoemulsification such as posterior capsule rupture, retinal detachment, progression of existing maculopathy, capsular phimosis, late lens dislocation and transient intraocular pressure elevation occur more frequently in highly myopic patients. As a result, it is extremely important that cataract surgeries of these patients are performed by experienced surgeons and that attention is paid to perioperative and postoperative complications.

Transscleral fixation of intraocular lens in the treatment of lens subluxation in children

This study evaluated the effectiveness and safety of IOL implantation with transscleral fixation using the knotless Z-suture technique in pediatric patients with congenital lens subluxation. The study included 24 children (36 eyes) with grade III congenital subluxation of the lens who underwent phacoaspiration of the subluxated lens with IOL implantation with transscleral fixation using the knotless Z-suture performed in the Kazakh Research Institute of Eye Diseases in Almaty in the period from 2017 to 2021. The average observation period was 31.7±11.3 months (2.0 to 4.5 years). The stability of the IOL position, the state of the intrascleral sutures, visual acuity after surgery, the presence and severity of complications in the long-term period were evaluated. All patients (100%) had a significant improvement in visual acuity after surgery. No intraoperative complications were registered in any of the cases. Postoperative complications were noted in 8.3% of cases (n=3). The final functional outcome of surgical treatment depended on the presence of concomitant pathology, the main cause of low vision was the development of refractive amblyopia due to refractive errors. The presented technique of transscleral fixation of IOL has proven to be reliable, which is especially important for pediatric patients considering their high physical activity and expected lifespan.

Myopia, what causes it and can it be avoided?

Myopia (short‐sightedness or near‐sightedness) is a condition of refraction where vision to distant is impaired. Axial elongation of the eye is the main anatomical cause of myopia.The prevalence of myopia has increased alarmingly fast globally. The estimation of WHO report was that in 2020 27% of world's population would be myopic, and if there will be no changes in the trend then by 2050 there would be 2.56 billion myopic people worldwide. Highest prevalence of myopia has been reported in many South and East Asian countries, where about 80% of the school leavers are myopic. Parental myopia increases the risks of myopia in their children, two myopic parents more than one. Genetic studies have been able to explain only small part of myopia, nor have been able to explain the differences in the prevalence between populations. Myopia relates to higher education, near work and higher occupational status and is mare rare in urban environment and in occupations where people work outdoors. In children myopia usually develop after they had begun attending school and is associated with more time spent on reading and near work and less time on outdoor activities.The major public health concerns connected with myopia are related to its complications. Myopia has become one of the main causes of vision loss due to complications, such as retinal detachment, macular degeneration and haemorrhage, choroidal neovascularization, and open angle glaucoma. The higher myopia is the higher is the risk of these complications. In countries where myopia is common, it is already a significant cause of low vision and blindness.In a Finnish study prevalence of myopia in 7‐ and 11‐year‐olds, was 0.5% and 3.3%, respectively, if daily near work did not exceed 1 h. Multiple regression model adjusted by sex, parental myopia and time spent outdoors, showed that 1 h increase in near work increased the risk of myopia 47% (95% CI 1.099–1.984, P = 0.010) and 35% (CI 1.170–1.548, P &lt; 0.001), in 7‐ and 11‐year‐olds, respectively. Each hour spent outdoors adjusted by sex, parental myopia and time spent outdoors decreased their same risk by 24% (95% CI 0.533–1050, P = 0.096 and 0.648–0.000, P = 0.001, respectively). Higher prevalence of myopia in girls could mainly be explained by their more time spent in near work and less time outdoors.Plenty of long‐term near viewing, and short viewing distance, combined with low amount of time outdoors are risk factors for myopia. Avoiding these factors is more important the younger the child is. It is recommended that the daily time spent outdoors in children should be at least equal to near work time. Early school starting age, increases the risk of myopia and high myopia, and consequently risk for myopia related complications. Great educational stress in young children should be avoided.

Effect of Lipids on Diabetic Retinopathy in a Large Cohort of Diabetic Patients after 10 Years of Follow-Up.

(1) Background: Diabetic retinopathy (DR) remains the leading cause of low vision and blindness in young adults of working age. Although the most important risk factors-such as the duration of diabetes mellitus (DM) and glycemic control measured by HbA1c-are known, the effects of lipids are not as clear. The aim of the present study is to analyze the effects of lipids on the development of DR. (2) Methods: This is a retrospective study of a population of 175,645 DM2 patients, during the period 2010 to 2020, in which the effects of different lipid factors are studied. (3) Results: The variables that most influenced the development of DR in our study, based on significance and cumulative hazard (CH), were arterial hypertension (CH 1.217, p < 0.001), HbA1c levels (CH 1.162, p = 0.001), microalbuminuria (CH 1.012, p < 0.001), LDL-C cholesterol (CH 1.007, p = 0.012), TC/HDL-C index (CH 1.092, p < 0.001), No-HDL-C/HDL-C index (CH 1.065, p = 0.002), the use of statins (CH 1.001, p = 0.005), and body mass index (CH 1.007, p < 0.001). (4) Conclusions: LDL-cholesterol, TC/HDL-C, and No-HDL-C/HDL-C indices are related to the development of DR, and there is a protective effect of HDL-cholesterol and the use of fibrates.

REPAIR CAPABILITIES OF ALLOGENIC STEM CELLS IN DISEASES OF THE ANTERIOR SEGMENT OF THE EYEBALL

Corneal diseases are one of the leading causes of low vision and blindness throughout the world, which serves to increase visual disability among the young and working-age population. The low effectiveness of therapeutic treatment, lack of donor material and frequent rejection reactions after transplantation prompt the search for more effective methods of treating corneal diseases, both inflammatory and dystrophic.

The New Era of Therapeutic Strategies for the Treatment of Retinitis Pigmentosa: A Narrative Review of Pathomolecular Mechanisms for the Development of Cell-Based Therapies.

Retinitis pigmentosa, defined more properly as cone-rod dystrophy, is a paradigm of inherited diffuse retinal dystrophies, one of the rare diseases with the highest prevalence in the worldwide population and one of the main causes of low vision in the pediatric and elderly age groups. Advancements in and the understanding of molecular biology and gene-editing technologies have raised interest in laying the foundation for new therapeutic strategies for rare diseases. As a consequence, new possibilities for clinicians and patients are arising due to the feasibility of treating such a devastating disorder, reducing its complications. The scope of this review focuses on the pathomolecular mechanisms underlying RP better to understand the prospects of its treatment using innovative approaches.

The possibility and practicality of glaucoma screening in modern society

Glaucoma is one of the main causes of low vision and irreversible blindness both in Russia and all over the world. Taking into account the huge budget expenditures of any country, both direct and indirect, required to provide ophthalmological care to a sufficiently large contingent of glaucoma patients, including annual losses of economic productivity associated with visual impairment, the practical importance of glaucoma screening is beyond doubt. In addition, identification of patients at the onset of the disease would allow earlier start of the treatment aimed at stabilizing the glaucoma process. However, the questions remain whether it is possible to perform glaucoma screening in current realities, as well as what research methods should be used. To find the answers to these questions, we reviewed the literature and analyzed modern publications on the problem of glaucoma screening in different countries.

Dual Sensory Impairment: Impact of Central Vision Loss and Hearing Loss on Visual and Auditory Localization.

In the United States, AMD is a leading cause of low vision that leads to central vision loss and has a high co-occurrence with hearing loss. The impact of central vision loss on the daily functioning of older individuals cannot be fully addressed without considering their hearing status. We investigated the impact of combined central vision loss and hearing loss on spatial localization, an ability critical for social interactions and navigation. Sixteen older adults with central vision loss primarily due to AMD, with or without co-occurring hearing loss, completed a spatial perimetry task in which they verbally reported the directions of visual or auditory targets. Auditory testing was done with eyes open in a dimly lit room or with a blindfold. Twenty-three normally sighted, age-matched, and hearing-matched control subjects also completed the task. Subjects with central vision loss missed visual targets more often. They showed increased deviations in visual biases from control subjects as the scotoma size increased. However, these deficits did not generalize to sound localization. As hearing loss became more severe, the sound localization variability increased, and this relationship was not altered by coexisting central vision loss. For both control and central vision loss subjects, sound localization was less reliable when subjects wore blindfolds, possibly due to the absence of visual contextual cues. Although central vision loss impairs visual localization, it does not impair sound localization and does not prevent vision from providing useful contextual cues for sound localization.

Compliance With the Use of Low-Vision Aids in a Greek Population: An Explorative Study.

The aim of this study is to investigate the compliance with low-vision aids (LVAs) among patients with low vision (LV) in a Greek population. An explorative study was conducted in a sample of patients with LV attending our outpatient unit at the School of Medicine, Aristotle University of Thessaloniki, Thessaloniki, Greece. Patients' demographics and daily visual demands were recorded, and they were administered with the National Eye Institute Visual Function Questionnaire-25 (VFQ-25) at baseline. Participants were trained in the use of a wide range of LVAs before their prescription. Evaluation of the use of the LVAs was conducted at one year after the baseline using a structured phone survey. A total of 100 LV patients were included, with 68% of them being older than 65 years and 50 being males. The main cause of LV (57.0%) was age-related macular degeneration, and the mean VFQ-25 score at baseline was 49.2 (SD= 17.8). Overall, 75 patients had been prescribed LVAs, with 76.0% of these patients preferring an optical aid. The vast majority (98.7%) of these patients stated using the LVA one year after the baseline, and 62.1% of them reported using the aid often to very often. Significantly, 76% of these patients reported that their quality of life was positively affected by the use of the aid, and 97.3% would recommend the use of LVA to another individual with the same problem. Providing appropriate training before the prescription is of high significance to improve the rate of compliance with the use of LVAs. These results can be used to develop appropriate strategies in this field.

Choroidal thickness and choroidal vascularity index changes in children with type 1 diabetes mellitus without retinopathy

BackgroundDiabetic retinopathy is one of the most important causes of low vision in the working age group. Retinopathy findings start earlier and have a worse prognosis in type 1 DM. The aim of the this study was to compare the choroidal thickness (CT) and choroidal vascular index (CVI) values of type 1 diabetes mellitus (DM) patients without retinopathy findings in pediatric patients and healthy children. MethodsThe study included 89 children, including 43 type 1 DM patients and 46 healthy controls. The age, gender, duration of DM, hemoglobin A1c (HbA1c), refractive error, intraocular pressure (IOP) and axial length (AL) of the participants were noted. CT measurements were performed subfoveally, 1000 µm from the fovea in the nasal and temporal quadrants. The total choroidal area (TCA), luminal area (LA) and stromal area (SA) were calculated using the binarization method using the image J program. The CVI was determined by dividing the luminal area by the total choroidal area. ResultsThere were no significant differences between the participants in terms of age, gender, spherical equivalent, IOP, and AL. There was no significant difference between the groups in terms of CT. TCA, LA and SA values were significantly higher in the Type 1 DM group (p=0.034, p=0.036, p=0.037, respectively). There was no significant difference between the groups in terms of the CVI. ConclusionsThe TCA, LA, and SA values were significantly higher in the type 1 DM group. LA/SA and CVI values were lower in the type 1 DM group, although not significantly. There was a negative correlation between the duration of DM and LA/SA as well as CVI. This suggests that vascular reduction starts in the early stages.

Long-term outcomes of single monocular resection-recession in adult sensory strabismus and factors affecting the postoperative drift.

The purpose of our study was to analyze the clinical characteristics and outcome of horizontal strabismus surgery in patients having sensory strabismus and to analyze the factors that affect the postoperative drift in these patients over a follow-up of three years. This was a retrospective case series. Patients aged ≥18 years, having low vision (visual acuity ≤20/60) in one eye, and undergoing horizontal strabismus surgery (standard recess-resect procedures) in the same eye were recruited. All patients were advised patching of the good eye six weeks prior and continued for six weeks post strabismus surgery. We excluded patients who had paralytic disorders, motility defects, or those with chronic systemic conditions. Patients with a minimum follow-up of three years were recruited. The study included 56 patients whose mean age was 22.9 ± 4.93 years. Exotropia (n = 38; 67.8%) was more common than esotropia (n = 18; 32.1%). Preoperative visual acuity was 1.1 ± 0.85 (range perception of light to 6/18p). The cause of low vision was amblyopia (n = 30; 53.5%) followed by trauma (n = 22; 39.2%). The mean preoperative distance deviation was 57.7 ± 15.5 PD in the primary position (range: 20-65 PD). The success rate of exotropia (78.9%) was more than esotropia (52.9%) at three years. Two patients with esotropia were overcorrected. All patients with exotropia showed an exotropic drift with time. The motor alignment after a single recession-resection procedure was satisfactory at the long-term in our cohort of sensory strabismus. The duration or extent of visual impairment had no relation to the postoperative outcome.

Demographic and Clinical Profile of Patients with Low Vision: A Hospital Based Study

Background: Vision impairment is a significant problem in our country. The purpose of this study was to evaluate the causes and to record the demographic profile of patients with low vision. Material &amp; Methods: After taking permission from ethical committee, the study was conducted on 250 patients presenting in low vision clinic of Regional Institute of Ophthalmology punjab in north India .A detailed examination and information regarding the demographic and clinical characteristics of the patients were recorded .the visual acuity of all the patients were determined using Snellen chart followed by anterior and posterior segment examination using a slit-lamp bio microscope and direct and /or indirect ophthalmoscope.Refraction was done in all the subjects and Best corrected visual acuity was recorded. Their demographic and clinical profile were analyzed using SPSS software. Results: Majority of the patients presenting with low vision were found to be above 56 years of age with higher prevalence in rural (54.40%) than in urban (45.60%) population. Male (65.60%)were predominant than females(34.40%) .Major etiological causes were Diabetic retinopathy 76 (30 .40%) followed by Pathological Myopia (21.20%), ARMD (14.80%), Retinitis pigmentosa (6.80%) and Glaucoma (6.00%). Conclusion: Diabetic retinopathy and pathological myopia were the predominant causes of low vision. Patients from rural background were more affected than urban areas.

Prevalence and causes of visual impairment and use of low-vision devices at a tertiary eye hospital in western Uttar Pradesh, India

Objectives: The objective of this study was to determine the hospital-based prevalence and major causes of visual impairment in patients attending the low-vision clinic of a tertiary eye institute. Materials and Methods: This study was a retrospective non-intervention hospital-based study. Clinical records of visually impaired patients presented to the department of low vision from February 2017 to December 2021 were retrieved. Blindness has been defined as the best-corrected distance visual acuity of &lt;3/60 and/or &lt;10° visual field in the better eye. Low vision was defined as a best-corrected distance visual acuity of &lt;6/18 but equal to or better than 3/60 in the better eye. The presenting visual acuity, causes of low vision and blindness, and prescribed low-vision devices were recorded and analyzed to determine the prevalence and major causes of visual impairment. Results: Among 414 visually impaired patients, the prevalence of low vision and blindness was 52.9% (n = 219) and 47.1% (n = 195), respectively. Retinitis pigmentosa (n = 57, 13.8%) and glaucoma (n = 43, 10.4%) were the major causes of low vision; however, glaucoma (n = 55, 13.3%) and cortical visual impairment (CVI) (n = 37, 8.9%) were the major causes of blindness. A total of 229 low-vision devices were dispensed, of them 166 (40.1%) were distance and 63 (15.1%) were near devices. Conclusion: The hospital-based prevalence of low-vision patients was more as compared to blindness. The major causes of visual impairment were retinitis pigmentosa, glaucoma, and CVI. A comprehensive approach to the causes of low vision and low-vision services is needed to reduce the burden of visual impairment in the country.

On classification approaches, terminology and modern principles of treatment of pathologies associated with high myopia. Part 1. Criteria for high myopia and pathological myopia

Myopic refraction is the most common ocular pathology, currently affecting about 1.5 billion people worldwide. Recent decades have seen a trend towards a significant increase in myopia prevalence, which is likely to continue in the near future. Therefore, we observe some kind of an epidemic of myopia. The greatest concern is caused by cases of uncorrectable visual impairment associated with myopia, which make pathological (degenerative) myopia one of the leading causes of low vision and blindness in many countries. At the same time, there is still no uniform interpretation of such important concepts as “high myopia” and “pathological myopia”, which can negatively affect various aspects of clinical and scientific interaction among ophthalmologists. The article provides an overview of modern work on the above issues and proposes definitions of terms to be used in the healthcare system of the Russian Federation

Evidence-based guidelines for diagnosis and treatment of age-related macular degeneration in China (2023)

Age-related macular degeneration (AMD) is the main cause of low vision and even blindness in the elderly. With the aging of our population, the number of AMD patients will continue to rise. In the past decade, the rapid development of ocular fundus imaging technology has provided a new perspective and approach for the classification, diagnosis and follow-up of AMD. The advent of new drugs has provided more diverse intervention and treatment methods for AMD, especially for neovascular AMD, and the emphasis on accurate and individualized treatment has put forward higher requirements for retinal specialists. Therefore, based on the latest evidence-based medical information, combined with the international guidelines and the current situation of China's social and economic development, experts from the Chinese Vitreo-Retinal Society of Chinese Medical Association, the Fundus Disease Group of Chinese Ophthalmologist Association, and the National Clinical Research Center for Eye Diseases gave recommendations around eight clinical problems and formed China's guidelines for the clinical diagnosis and treatment of AMD. With the implementation of these guidelines, we can standardize the diagnosis, treatment, prevention and follow-up of AMD in China.

Problems and prospects of new methods of light stimulation in visual rehabilitation

Neurodegenerative retinal diseases such as age-related macular degeneration, glaucoma, and diabetic retinopathy remain the leading causes of low vision and blindness worldwide. Visual rehabilitation of patients who are visually impaired due to neurodegenerative diseases of the retina requires solving problems associated with a violation of the structure of neural networks and a deficiency of visual functions provided by these networks. Despite certain successes in the application of innovative methods of therapy, it is important to develop new approaches to visual rehabilitation to improve the quality of life of visually impaired patients. In visual rehabilitation, not only medical, but also various non-pharmacological therapy strategies are widely used to protect and restore the structure of the retina and its function. Among them, a separate niche is occupied by the technologies of vision stimulation therapy (phototherapy), the analysis of the main aspects of which is the task of this review. The vector of new research in the field of phototherapy is aimed at developing methods that can maximize the plasticity of the visual system to increase the effectiveness of its protection and recovery in neurodegenerative pathology. In this regard, new technologies of fractal phototherapy have great potential in visual rehabilitation.

Глаукома псевдофакичного глаза

Relevance. Currently, there is a steady increase in the age-associated eye diseases worldwide. First of all, this applies to such ocular diseases as age-related maculodegeneration (AMD), glaucoma and cataracts. Despite the development and standardization of surgical techniques, the widespread introduction of cataract phacoemulsification, appearance of many modifications of anti-glaucomatous surgery, and the active use of angiogenesis inhibitors used to treat AMD, these diseases continue to occupy a leading position in the causes of low vision and blindness. Purpose. To reveal the problem of the development of pseudophakic glaucoma in patients who underwent surgical treatment for cataracts. Material and methods.To complete this review, we searched for literature sources on the PubMed and Scopus abstract databases for the period up to 2021 inclusive. In total, 53 articles related to the topic of the review were selected. The beginning of publications on this topic dates back to 1963. Results. At risk are patients with pseudoexfoliative syndrome, high-grade myopia, traumatic, diabetic and uveal cataracts. Pseudophakic glaucoma can also be caused by intraoperative (iris damage, vitreous prolapse, implantation of an intraocular lens outside the capsular bag, incomplete viscoelastic washout) and postoperative complications (inflammatory process, hyphema, dislocation of the artificial lens, pupillary block or Ellingson syndrome). Conclusion. Pseudophakic glaucoma, although rare, is quite formidable, which can reduce result of cataract surgery. Key words: pseudophakic glaucoma, glaucoma, cataract, ophthalmohypertension, complications of phacoemulsification