Utilisation of eyecare services in an urban population in southern India: the Andhra Pradesh eye disease study

AIM: To assess utilisation of eyecare services by people with visual impairment <6/18 or equivalent visual field loss in the better eye in the urban population of Hyderabad in southern India. METHODS: 2522 subjects of all ages, representative of the population of Hyderabad city, underwent a detailed interview and dilated examination as part of the population based Andhra Pradesh eye disease study. Subjects more than 15 years of age were interviewed regarding the use of eyecare services. RESULTS: Of 250 subjects with presenting distance visual acuity <6/18 or equivalent visual field loss in the better eye, information on utilisation of eyecare services was available for 229 (91.6%). Of these 229 subjects, 44 (19%) had visual acuity <6/60 or equivalent visual field loss in the better eye, and 202 (88.2%) had noticed decrease in vision over the past 5 years. Multivariate analysis showed that this decrease in vision was noticed significantly less by subjects with refractive error as the cause of visual impairment (odds ratio 0.34, 95% confidence interval 0.12-0.93). Of the 229 subjects who were visually impaired, 108 (59%) did not seek treatment. Multivariate analysis revealed that the odds for seeking treatment were significantly lower for Hindus than Muslims (odds ratio 0.53, 95% confidence interval 0.28-0.98). The reasons for not seeking treatment could be classified as personal (49.5%), economic (30.8%), and social (19.6%). CONCLUSION: A large proportion of subjects with visual impairment in this urban population in India did not seek treatment even after noticing decrease in vision. Projecting these data to the 155 million urban population >15 years of age in India, there may be 4.9 million (95% confidence interval 4.3-5.5 million) people in urban India who are not seeking treatment for their visual impairment even after noticing decrease in vision. These data suggest that efforts have to be made to better understand the reasons for this phenomenon so that optimal utilisation of the available eyecare services in urban India can be planned.     

Ocular Genetics Program: multidisciplinary care of patients with ocular genetic eye disease

BACKGROUND: Patients who suffer from ocular genetic diseases have special needs in terms of diagnosis and management of rare entities, low-vision needs, genetic counselling, and psychosocial adjustments that are usually not addressed by an ophthalmologist alone. The Ocular Genetics Program (OGP) at the Hospital for Sick Children, Toronto, was established in 1994 to provide comprehensive, multidisciplinary care of patients with inherited eye disorders. We now assess the benefits of such a program and of integrating research into the care of patients. METHODS: We report our experience in developing a multidisciplinary ocular genetics program and the results of a pilot patient satisfaction survey that involved 61 patients. RESULTS: The OGP multidisciplinary aspects are described. Of the 61 patients surveyed, 98% stated that they were satisfied with the OGP; 93%-96% of patients were content with "one day of appointments", "understanding of eye problem", and "coordination of ancillary tests such as visual fields test, electrophysiology, and others"; and for 70%-86% of respondents "waiting time to get an appointment", "information received on current research", and "primary health care provider adequately informed" were satisfactory. INTERPRETATION: The OGP is a unique service in Canada, which strives to provide the comprehensive care needed by ocular genetic patients. High patient satisfaction is an indicator of the success of this approach. Long waiting times for appointments and application of laboratory research in clinical care remain challenging.     

Immune modulated inflammation of the ocular surface — a change of paradigm in the understanding of dry eye disease

Immune based inflammation represents an important new approach to the understanding of dry eye disease and is able to cause a negative feedback on protective mechanisms of the ocular surface.     

Toll-like receptors in ocular immunity and the immunopathogenesis of inflammatory eye disease

Microbial agents have an important role in the pathogenesis of various inflammatory eye diseases, such as uveitis and keratitis. Microbial infections of the eye such as microbial keratitis, ocular onchocerciasis, bacterial endophthalmitis, viral retinitis, and other infectious uveitis are unfortunately common. In addition, microbial agents have been implicated in the pathogenesis of "non-infectious" immune mediated diseases such as HLA-B27 associated acute anterior uveitis. Toll-like receptors (TLR) are a family of pattern recognition receptors that initiates rapid host innate immune response to microbial components known as pathogen associated molecular patterns, which are unique to a given class of microbes, such as lipopolysaccharide of Gram negative bacteria. Recent in vitro and in vivo studies have demonstrated the expression and function of TLRs in the eye, with significant implications for better understanding of ocular immunity and the pathogenesis of inflammatory eye diseases affecting the cornea, uvea, and retina.     

Melatonin in the eye: implications for glaucoma

Melatonin synthesis occurs in the retina of most animals as well as in humans. Circadian oscillators that control retinal melatonin synthesis have been identified in the eyes of different animal species. The presence of melatonin receptors is demonstrable by immunocytochemical studies of ocular tissues. These receptors may have different functional roles in different parts of the eye. In view that melatonin is a potent antioxidant molecule, it can be effective in scavenging free radicals that are generated in ocular tissues. By this mechanism melatonin could protect the ocular tissues against disorders like glaucoma, age-related macular degeneration, retinopathy of prematurity, photo-keratitis and cataracts. Although an increased intraocular pressure is an important risk factor in glaucoma, other concomitant phenomena like increased glutamate levels, altered nitric oxide metabolism and increased free radical generation seem to play a significant role in its pathogenesis. Data are discussed indicating that melatonin, being an efficient antioxidant with antinitridergic properties, has a promising role in the treatment and management of glaucoma.     

Advances in the diagnosis and therapy for diseases of the ocular surface: dry eye and ocular allergies

The 77th meeting of the Association for Research in Vision and Ophthalmology (ARVO) presented the latest developments in clinical research and practice across a range of ophthalmic disciplines. Of particular interest was the current status of research in dry eye and ocular allergy. With these conditions being very common to ophthalmologists, and the fact that they are difficult to differentiate due to the number of overlapping symptoms, there remains a need for more rapid and accurate methods for their diagnosis. Therefore, a number of new tools were presented that have the potential for use in clinical trials and practice to improve the diagnosis and assessment of dry eye and ocular allergy. Some of these tools have been developed based on a greater understanding of the pathophysiology of dry eye and ocular allergy, and the various molecular pathways involved. Indeed, a greater understanding of the molecular mechanisms involved in the pathogenesis of dry eye and ocular allergy has identified potential targets for the treatment of these conditions. Continuing research into new agents can provide ophthalmologists with a number of options that will ultimately benefit the patient.     

Impact of aging on the pathophysiology of dry eye disease: A systematic review and meta-analysis

PurposeDry eye disease (DED) is a common age-related ocular surface disease. However, it is unknown how aging influences the ocular surface microenvironment. This systematic review aims to investigate how the aging process changes the ocular surface microenvironment and impacts the development of DED.MethodsAn article search was performed in PubMed, EMBASE, and Web of Science. 44 studies reporting on age-related ocular changes and 14 large epidemiological studies involving the prevalence of DED were identified. 8 out of 14 epidemiological studies were further analyzed with meta-analysis. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) reporting guidelines were followed. Study-specific estimates (impact of aging on the prevalence of DED) were combined using one-group meta-analysis in a random-effects model.ResultsMeta-analysis revealed the prevalence of DED in the elderly aged 60 years old or older was 5519 of 60107 (9.2%) and the odds ratio of aging compared to younger age was 1.313 (95% confidence interval [CI]; 1.107, 1.557). With increasing age, the integrity of the ocular surface and tear film stability decreased. Various inflammatory cells, including senescent-associated T-cells, infiltrated the ocular surface epithelium, lacrimal gland, and meibomian gland, accompanied by senescence-related changes, including accumulation of 8-OHdG and lipofuscin-like inclusions, increased expression of p53 and apoptosis-related genes, and decreased Ki67 positive cells.ConclusionsThe aging process greatly impacts the ocular surface microenvironment, consequently leading to DED.     

Character of ocular surface mucins and their alteration in dry eye disease

At the ocular surface, three types of mucins are present. The large gel-forming mucin MUC5AC is expressed by conjunctival goblet cells. Some cells of the lacrimal gland acini express the small soluble mucin MUC7. The corneal and conjunctival epithelia express the membrane-associated mucins MUCs 1, 4, and 16. With the characterization of the mucin gene repertoire of the ocular surface epithelia, studies of the function of specific mucins, their gene regulation, and their alteration in ocular surface disease have begun. Current information suggests that all the mucins are hydrophilic and play a role in maintenance of water on the surface of the eye. The large secreted mucins represent the "janitorial service" that moves over the surface of the eye to wrap up and remove debris. The membrane-associated mucins form the glycocalyx, which provides a continuous barrier across the surface of the eye that prevents pathogen penetrance and has signaling capabilities that influence epithelial activity. Factors regulating mucin gene expression include retinoic acid, serum, and dexamethasone. Alteration in both secreted and membrane-associated mucins occur in drying ocular surface diseases. In Sjogren syndrome, MUC5AC expression is reduced, and in non-Sjogren dry eye, glycosylation of MUC16 appears to be altered. The pattern of expression of enzymes that glycosylate mucins is altered in ocular cicatricial pemphigoid. Therapies being evaluated for dry eye, including cyclosporine A, P2Y2 agonists, gefarnate, 15-(S)-HETE, and corticosteroids, may be efficacious due to their effect on mucin gene expression and secretion.     

Reliability of Chinese web-based ocular surface disease index questionnaire in dry eye patients: a randomized, crossover study

AIM: To investigate the causal gene mutation and clinical characteristics in two Chinese families with autosomal dominant congenital coralliform cataracts. METHODS: Two unrelated Chinese pedigrees with congenital cataract were investigated. Routine ophthalmic examinations were performed on all patients and non-affected family members. Peripheral blood samples were collected, and the genomic DNAs were extracted. The coding regions of probands’ DNAs were analyzed with cataract gene panel. The identified gene was amplified by polymerase chain reaction and sequenced in other members of two families to verify if the mutated gene was co-segregated with the disease. RESULTS: Congenital coralliform cataract was inherited in an autosomal dominant mode in both pedigrees. For each family, more than half of the family members were affected. All patients presented with severe visual impairment after birth as a result of bilateral symmetric coralliform lens opacification. An exact same defect in the same gene, heterozygous mutation of c.70C>A (p. P24T) in exon 2 of γD-crystallin CRYGD gene, was identified in both probands from each family. Sanger sequencing analysis demonstrated that the mutated CRYGD was co-segregated in these two families. CONCLUSION: A known substitution c.70C>A (p. P24T) in CRYGD gene appears to be the disease-causing gene in these two Chinese families. It is known that mutated CRYGD caused most of the congenital coralliform cataracts, suggesting that the CRYGD gene are associated with phenotype of congenital coralliform cataract.     

Exploring topical anti-glaucoma medication effects on the ocular surface in the context of the current understanding of dry eye

Purpose

To assess tear film parameters, ocular surface characteristics, and dry eye symptomology in patients receiving topical anti-glaucoma medications.

不同方法矫治麻风性兔眼对视功能和眼组织损害的对比研究

目的:探讨不同手术方法矫治麻风性兔眼所引起的术后并发症和对患者视觉质量的影响.方法:回顾性临床对照研究.选择我院2007-05/2015-09采用不同方法矫治麻风性兔眼的患者68例97眼,包括尼龙线矫治术、眼睑缝合术、颞肌移位术.观察术后6mo的最佳矫正视力变化,对其术后并发症(溢泪、泪道损伤、睁眼困难、内外眦部感染和泪器组织的瘢痕化改变)的发生率进行组间比较.结果:三种手术方法术后对患者视力的影响:尼龙线矫治术和眼睑缝合术患者手术前后视力差异具有统计学意义(Ζ=-4.193、-4.213,P<0.05);颞肌移位术患者手术前后视力变化的差异无统计学意义(Ζ=-1.532,P>0.05).术后并发症:(1)溢泪:尼龙线矫治术占91%,眼睑缝合占89%,颞肌移位术占59%,三者比较差异具有统计学意义(χ2=12.198,P<0.05);(2)泪器损伤:尼龙线矫治术占66%,眼睑缝合术占95%,颞肌移位占41%,三者比较差异具有统计学意义(χ2=22.415,P<0.05);(3)睁眼困难:尼龙线矫治术占56%,眼睑缝合术占55%,颞肌移位术占22%,三者比较差异具有统计学意义(χ2=8.795,P<0.05);(4)术后感染:尼龙线术占84%,眼睑缝合术占3%,颞肌移位占11%,三者比较差异具有统计学意义(χ2=60.858,P<0.05).结论:麻风性兔眼手术矫治虽有一定的临床效果,尤其是颞肌移位术后患者能主动闭眼,其视力、视觉质量无显著变化.提示该手术可预防角膜的暴露性损害.但手术造成的医源性损伤与其他组间患者的视觉质量下降和眼组织损害(溢泪、泪道损伤、内外眦部感染、泪器组织瘢痕化等)应引起足够的重视.     

眼表微生态在干眼发生发展中作用机制研究进展

眼表微生态由寄居于人体结膜囊的微生物种群形成.正常人眼表微生态相对稳定,主要存在葡萄球菌、棒状杆菌、丙酸杆菌和链球菌等共生菌.干眼患者眼表存在一定程度的微生态失衡及微生物种群的差异,出现痤疮丙酸杆菌、肺炎克雷伯菌、产酸克雷伯菌和红球菌等,且与致病菌共享代谢途径增多.微生态变化可致眼表出现一定程度免疫介导的炎性反应,眼表树突状细胞活跃,细胞因子释放,杯状细胞和角膜上皮下神经损伤,引起干眼症状.     

MMPs in the eye: emerging roles for matrix metalloproteinases in ocular physiology

Matrix metalloproteinases (MMPs) are a family of proteolytic enzymes that function to maintain and remodel tissue architecture. Their substrates represent an astounding variety of extracellular matrix components, secreted cytokines and cell surface molecules, and they have been implicated in a wide range of processes and diseases. To date MMPs have been found in virtually every tissue of the eye under conditions of health and disease. Although their functions in vivo remain poorly understood, it is clear they impact on essentially every aspect of eye physiology. This chapter reviews the expanding literature on MMPs in the eye and attempts to place it in the context of basic MMP biology. A general overview of MMP functions is presented first, and then the discussion moves to examples of possible MMP roles in two eye structures. For the cornea, we present recent work on the roles of MMPs during various aspects of wound healing. For the retina, we describe the activities of MMPs in specific disease states from which common principles may emerge.