Referral patterns to an ophthalmic outpatient clinic by general practitioners and ophthalmic opticians and the role of these professionals in screening for ocular disease.

Case notes of 1113 consecutive new patients referred to a consultant ophthalmologist at a district general hospital were reviewed to determine the source and efficacy of referrals and the current screening practices of general practitioners and ophthalmic opticians. General practitioners initiated referral in 546 cases (49%) and ophthalmic opticians referral in 439 (39%). Visual loss or visual disturbance was the most important single reason for referral (345 cases; 31%), followed by suspected glaucoma (145 cases; 13%), abnormalities of binocular vision (140; 12.5%), disorders of eyelids or ocular adnexa (127; 11%), and red eye (86; 8%). General practitioners referred many more patients with disorders of the eyelids and adnexa and ophthalmic opticians many more patients with suspected glaucoma. Ophthalmic opticians were far more likely than general practitioners to refer patients with suspected glaucoma correctly. A total of 180 patients (16%) were referred from ocular screening, in 149 cases by ophthalmic opticians and in 10 by general practitioners. Seventy patients had glaucoma or incomplete features of glaucoma, all of them referred by ophthalmic opticians. Of eight diabetic patients referred by ophthalmic opticians, three had asymptomatic disease and in two diabetes was diagnosed as a result of ocular screening. No patient was referred for asymptomatic diabetic retinopathy from screening by general practitioners. Ophthalmic opticians were more likely than general practitioners to diagnose retinopathy requiring photocoagulation. Use of a community based service to screen for glaucoma could save unnecessary consultant outpatient appointments. A similar service could facilitate detection of diabetic retinopathy at a stage when treatment is most effective.     

Prevention of blindness by screening for diabetic retinopathy: a quantitative assessment.

Diabetic retinopathy is an important cause of blindness in the Western World. A review of the randomised trials of laser photocoagulation of the retina as a method of preventing blindness from this disorder showed that this treatment is very effective, reducing the risk of blindness by 61% in a treated eye. As only one eye is needed for sight the reduction in blindness in a population will be greater than 61% because the effect of treatment in one eye is not always identical with the effect in the other eye. For analysis this reduction was taken as 73%, representing the average of the minimum and maximum estimates (61% and 85%). The effectiveness of this treatment suggests that there is the potential for a national screening programme to bring about a major reduction in blindness from this cause. A quantitative assessment of the effect of screening indicated that a programme in which patients with diabetes mellitus are systematically referred to ophthalmic opticians for a retinal examination could detect 88% of all diabetics with serious retinopathy and that 87% of these cases would be treatable. Screening and early treatment of retinopathy would prevent deterioration of visual acuity and could reduce the risk of blindness due to diabetic retinopathy by an estimated 56% (0.73 X 0.88 X 0.87). The findings suggest that an effectively managed community based screening programme encompassing detection, referral, treatment, and follow up would prevent about 260 new cases of blindness in diabetics under the age of 70 each year in England and Wales. This would represent over 10% of all cases of blindness in adults in this age group.     

Adding retinal photography to screening for diabetic retinopathy: a prospective study in primary care.

OBJECTIVE--To evaluate whether adding retinal photography improved community screening for diabetic retinopathy. SETTING--Mobile screening unit at rural and urban general practices in south west England. SUBJECTS--1010 diabetic patients from primary care. DESIGN--Prospective study; patients were examined by ophthalmoscopy by general practitioners or opticians without fundal photographs and again with photographs, and assessments were compared to those of an ophthalmologist. MAIN OUTCOME MEASURES--Whether fundal photography improved the sensitivity of detection of retinopathy and referrable diabetic retinopathy, and whether this sensitivity could be improved by including a review of the films by the specialist. RESULTS--Diabetic retinopathy was detected by the ophthalmologist in 205 patients (20.5%) and referrable retinopathy in 49 (4.9%). The sensitivity of the general practitioners and opticians for referrable retinopathy with ophthalmoscopy was 65%, and improved to 84% with retinal photographs. General practitioners'' sensitivity in detecting background retinopathy improved with photographs from 22% to 65%; opticians'' sensitivity in detecting background retinopathy improved from 43% to 71%. The sensitivity of detecting referrable retinopathy by general practitioners improved from 56% to 80% with photographs; for opticians it improved from 75% to 88%. CONCLUSIONS--Combining modalities of screening by providing photography with specialist review of all films in addition to direct ophthalmoscopy through dilated pupils improves assessment and referral for diabetic retinopathy by general practitioners and opticians. With further training and experience, primary care screeners should be able to achieve a sensitivity that will achieve an effective, acceptable, and economical community based screening programme for this condition.     

Referral routes to hospital of patients with chronic open-angle glaucoma.

An analysis of the referral routes of Southampton Eye Hospital of 191 patients who had been diagnosed as having chronic open-angle glaucoma showed that 121 patients (63.4%) were diagnosed as a result of the patient seeking advice for ocular symptoms (118) or because they had a family history of glaucoma (3). Advice had been sought from general practitioners (48), ophthalmic medical practitioners (19), and ophthalmic opticians (46). The remaining eight patients had gone directly to the casualty department. Seventy patients had been identified by chance, the majority of ophthalmic medical practitioners (26) or ophthalmic opticians (32).     

Prevalence of retinopathy in a diabetic clinic.

In a prospective study lasting 14 months an attempt was made to measure the visual acuity and examine the fundi, after mydriasis, of all patients attending the diabetic clinic of a district general hospital. Of 704 patients, 160 (22.7%) had some evidence of retinopathy, and 52 (7.4%) of these were already attending an ophthalmologist. A further 18 (2.6%) were known to have retinopathy and were being followed up in the diabetic clinic. Ninety (12.8%) new patients with diabetic retinopathy were discovered. Most had minimal changes, but 30 (4.3%) were considered to have changes severe enough to be referred to an ophthalmologist. Twenty-two (2.1%) underwent, or were awaiting, photocoagulation, and half of these had had no visual symptoms when first seen. Although some of these patients were already being treated or observed for retinopathy, it is encouraging that relatively few new patients needing treatment for retinopathy were discovered. If retinopathy could be detected early enough physicians might be able to deal with it and so ease pressure on ophthalmological services.     

Comparison of non-mydriatic retinal photography with ophthalmoscopy in 2159 patients: mobile retinal camera study.

OBJECTIVE--To determine whether non-mydriatic Polaroid retinal photography was comparable to ophthalmoscopy with mydriasis in routine clinic screening for early, treatable diabetic retinopathy. DESIGN--Prospective study of ophthalmoscopic findings according to retinal camera screening and ophthalmoscopy and outcome of referral to ophthalmologist. SETTING--Outpatient diabetic clinics of three teaching hospitals and three district general hospitals. PATIENTS--2159 Adults selected randomly from the diabetic clinics, excluding only those registered as blind or those in wheelchairs and unable to enter the screening vehicle. MAIN OUTCOME MEASURES--Numbers of patients and eyes correctly identified by each technique as requiring referral with potentially treatable retinopathy (new vessel formation and maculopathy) and congruence in numbers of microaneurysms, haemorrhages, and exudates reported. RESULTS--Camera screening missed two cases of new vessel formation and did not identify a further 12 but indicated a need for referral. Ophthalmoscopy missed five cases of new vessel formation and indicated a need for referral in another four for other reasons. Maculopathy was reported in 147 eyes with camera screening alone and 95 eyes by ophthalmoscopy only (chi 2 = 11.2; p less than 0.001), in 66 and 29 of which respectively maculopathy was subsequently confirmed. Overall, 38 eyes received laser treatment for maculopathy after detection by camera screening compared with 17 after ophthalmoscopic detection (chi 2 = 8.0; p less than 0.01). Camera screening underestimated numbers of microaneurysms (chi 2 = 12.9; p less than 0.001) and haemorrhages (chi 2 = 7.4; p less than 0.01) and ophthalmoscopy underestimated hard exudates (chi 2 = 48.2; p less than 0.001). CONCLUSIONS--Non-mydriatic Polaroid retinal photography is at least as good as ophthalmoscopy with mydriasis in routine diabetic clinics in identifying new vessel formation and absence of retinopathy and is significantly better in detecting exudative maculopathy.     

Age-related macular degeneration: what can a family physician do?

Age-related macular degeneration (ARMD) is the most common cause of blindness in Canada, and, as the name suggests, its incidence increases rapidly with age. Atrophic maculopathy, one of the forms of ARMD, is associated with only mild to moderate visual loss but is not treatable. On the other hand, exudative maculopathy, another form, is characterized by the formation of neovascular membranes and causes acute visual disturbances; however, it is potentially treatable by means of laser photocoagulation. In symptomatic patients blood, lipids or serous fluid seen on funduscopic examination indicates occult neovascularization, even if no neovascular membrane is visible. In asymptomatic patients their age, the presence of soft drusen and the coarse pigmentary disturbance have the greatest correlation with the risk of neovascularization. Suitability for laser photocoagulation depends on the stage of exudative maculopathy, the duration of symptoms and the patient''s visual acuity. Therefore, family physicians must know what the earliest symptoms are and how to identify patients at highest risk so that intervention in terms of education, screening and prompt referral to an ophthalmologist for confirmation and subsequent treatment can be instituted.     

Quality of screening for diabetic retinopathy in the Rijeka region of Croatia

The aim of this study was to compare the quality of screening for diabetic retinopathy in cities of Rijeka and Zagreb, Croatia. Review of a random sample of 500 diabetic patient records and prospective ophthalmologic survey of 466 randomly selected diabetic patients in a secondary level diabetologic service in Rijeka (coastal region of Croatia). The main outcome measures were proportion of diabetic patient records with notes on ophthalmologic examination; rate of diabetic patients involved with screening for diabetic retinopathy; comparison with rates in Zagreb (Croatian capital). A total of 67% patients visited the ophthalmologist at least once after diagnosed with diabetes, and notes on ophthalmologic examination were found in only 28% patient records. Fifty percent of patients underwent an ophthalmologic examination within two years. Only one third of patients diagnosed with DM in last two years visited the ophthalmologist within this time, and 14% of patients older than 50 years never visited the ophthalmologist. Model of screening for diabetic retinopathy in Croatia works better in Zagreb than in Rijeka region, and needs certain improvements. The authors suggested modern methods of screening, the incorporation of the mechanisms of quality control, the obligatory reporting of newly diagnosed diabetic patients to the national registry, and the direct referral from diabetologist to ophthalmologist.     

Potent antiemetic effects of the new serotonin antagonists.

Diabetic retinopathy progresses through three distinct stages. A rational approach to management is based on an understanding of the pathophysiology of each stage. Based on the results of national multicentered clinical trials of laser photocoagulation and other treatments, advances in our understanding of the pathogenesis and treatment can now make a dramatic impact on blindness in the diabetic population: Panretinal laser photocoagulation treatment can reduce the risk of vision loss from high-risk proliferative diabetic retinopathy by at least 50%. Laser photocoagulation treatment of clinically significant diabetic macular edema can reduce the risk of vision loss by more than 50%. Vitrectomy can restore useful vision to some patients with severe diabetic retinopathy and vitreous hemorrhage with or without an accompanying traction retinal detachment. Diabetes 2000 is a new project sponsored by the American Academy of Ophthalmology, the goal of which is to eliminate preventable blindness from diabetes by the year 2000. As its name implies, Diabetes 2000 will be a long-term project aimed at a specific disease--diabetic retinopathy and its complications. It will provide the latest research findings to ophthalmologists and primary care physicians as the first priority, followed by the education of patients and the general public. Recent advances and treatment guidelines for the medical and surgical treatment of diabetic eye disease will be emphasized through the continuing education of ophthalmologists, other physicians, and allied health professionals. In later phases, educational programs for diabetic persons and the public will be developed.(ABSTRACT TRUNCATED AT 250 WORDS)     

Impact of diabetes on alpha-crystallins and other heat shock proteins in the eye

Diabetes and its related complications represent a major growing health concern and economic burden worldwide. Ocular manifestations of diabetes include cataractogenesis and retinopathy, the latter being the leading cause of blindness in the working-age population. Despite numerous studies and recent progress, the exact pathophysiology of the disease remains to be fully elucidated and development of new and improved therapeutic strategies for this chronic condition are greatly needed. Heat shock proteins (Hsps) are highly conserved families of proteins, which are generally regarded as protective molecules that play a wide variety of roles and can be expressed in response to different types of cellular stresses. In recent years, numerous studies have reported their implication in various ocular diseases including diabetic retinopathy. The present review focuses on the potential implication of Hsps in ocular diabetic complications and discusses their specific mechanisms of regulation with respect to their expression, functions and alteration during diabetes. The review will conclude by examining the potential of Hsps as therapeutic agents or targets for the treatment of diabetic retinopathy.     

糖尿病视网膜病变的基因治疗

糖尿病视网膜病变（diabetic retinopathy,DR）是糖尿病的主要并发症之一,大量的研究表明DR早期表现为视网膜神经细胞退化性改变,晚期出现新生血管及增殖膜,目前尚没有有效的治疗方法,严重危害患者视力。基因治疗为探索DR的治疗方法提供了新的手段,本文就目前DR的基因治疗研究现状和进展作一综述。     

Study of diagnostic accord between general practitioners and an ophthalmologist.

OBJECTIVES--To identify diagnostic accord and disagreement between general practitioners and an ophthalmologist and thereby determine how undergraduate and non-specialist postgraduate ophthalmic training could be improved. DESIGN--Comparison of diagnosis of presenting conditions by general practitioners and one ophthalmologist in patients consulting general practitioners for ophthalmic problems during March 1989 to February 1990. SETTING--12 general practices in west Nottingham. PATIENTS--1474 patients presenting to the study general practitioners with new ophthalmic conditions or new episodes of recurrent conditions. MAIN OUTCOME MEASURES--Diagnoses of general practitioners and ophthalmologist. RESULTS--1121 (76%) of patients with eye problems agreed to see the ophthalmologist and most were seen within three days. Sufficient data for comparison were available on 1103 patients. Diagnostic agreement was found in 638 cases (58%), but potentially serious misdiagnosis was found in only 15 cases; management in three of these cases would have ensured later identification. Most commonly confused conditions were infective and allergic conjunctivitis, blepharitis, and dry eyes. General practitioners assessed visual acuity in only 114 cases yet eight of the 15 patients seriously misdiagnosed had reduced acuity, an important diagnostic sign. CONCLUSIONS--Most ophthalmic disease seen in general practice does not require specialised equipment for diagnosis. Most cases of misdiagnosis have no serious consequences for the patient. Undergraduate and postgraduate training in ophthalmology should ensure that common conditions can be easily differentiated and more serious conditions identified and referred.     

Sirtuin1 Over-Expression Does Not Impact Retinal Vascular and Neuronal Degeneration in a Mouse Model of Oxygen-Induced Retinopathy

Proliferative retinopathy is a leading cause of blindness, including retinopathy of prematurity (ROP) in children and diabetic retinopathy in adults. Retinopathy is characterized by an initial phase of vessel loss, leading to tissue ischemia and hypoxia, followed by sight threatening pathologic neovascularization in the second phase. Previously we found that Sirtuin1 (Sirt1), a metabolically dependent protein deacetylase, regulates vascular regeneration in a mouse model of oxygen-induced proliferative retinopathy (OIR), as neuronal depletion of Sirt1 in retina worsens retinopathy. In this study we assessed whether over-expression of Sirtuin1 in retinal neurons and vessels achieved by crossing Sirt1 over-expressing flox mice with Nestin-Cre mice or Tie2-Cre mice, respectively, may protect against retinopathy. We found that over-expression of Sirt1 in Nestin expressing retinal neurons does not impact vaso-obliteration or pathologic neovascularization in OIR, nor does it influence neuronal degeneration in OIR. Similarly, increased expression of Sirt1 in Tie2 expressing vascular endothelial cells and monocytes/macrophages does not protect retinal vessels in OIR. In addition to the genetic approaches, dietary supplement with Sirt1 activators, resveratrol or SRT1720, were fed to wild type mice with OIR. Neither treatment showed significant vaso-protective effects in retinopathy. Together these results indicate that although endogenous Sirt1 is important as a stress-induced protector in retinopathy, over-expression of Sirt1 or treatment with small molecule activators at the examined doses do not provide additional protection against retinopathy in mice. Further studies are needed to examine in depth whether increasing levels of Sirt1 may serve as a potential therapeutic approach to treat or prevent retinopathy.     

Funduscopic examination of patients with diabetes who are admitted to hospital.

The charts of 123 patients with diabetes mellitus who were admitted to hospital were reviewed; 35 (28%) did not undergo funduscopic examination to detect diabetic retinopathy, and in 27 (22%) the examination was inadequate. Only four patients were referred to an ophthalmologist. Evidence of nephropathy and admission for diabetes control did not increase the probability of funduscopic examination. The findings suggest that house staff lack awareness of the natural history of diabetic retinopathy and of the success of current treatment. Annual funduscopic examination by an ophthalmologist in patients with diabetes is recommended, from the time of diagnosis in those with type II diabetes and starting 8 to 10 years after diagnosis in those with type I diabetes.     

Colour blindness distribution in the male population of Rome

A total of 3,285 young males selected at random from the school population of Rome have been administered the Ishihara plates for colour blindness. Those who failed to read all plates correctly were further administered Farnsworth's Panel D-15 and the diagnoses of colour blindness were made by an ophthalmologist and cross checked. A total of 201 subjects were found to be colour-blind, allowing a gene frequency estimate of 0.061 +/- 0.004. This is the first reliable estimate for the Italian population and appears to be lower than for other Caucasoid populations. The gene frequency of colour blindness is known to increase from 0.02-0.04 in 'primitive' populations to 0.07-0.09 in Caucasoid populations, possibly as a result of a selection relaxation.     

Therapeutic action of the mitochondria-targeted antioxidant SkQ1 on retinopathy in OXYS rats linked with improvement of VEGF and PEDF gene expression

The incidence of age-related macular degeneration (AMD), the main cause of blindness in older patients in the developed countries, is increasing with the ageing population. At present there is no effective treatment for the prevailing geographic atrophy, dry AMD, whereas antiangiogenic therapies successful used in managing the wet form of AMD. Recently we showed that mitochondria-targeted antioxidant plastoquinonyl-decyl-triphenylphosphonium (SkQ1) is able to prevent the development and moreover caused regression of pre-existing signs of the retinopathy in OXYS rats, an animal model of AMD. Here we examine the effects of SkQ1 on expression of key regulators of angiogenesis vascular endothelial growth factor A (VEGF) and its antagonist pigment epithelium-derived factor (PEDF) genes in the retina of OXYS rats as evidenced by real-time PCR and an ELISA test for VEGF using Wistar rats as control. Ophthalmoscopic examinations confirmed that SkQ1 supplementation (from 1.5 to 3 months of age, 250 nmol/kg) prevented development while eye drops SkQ1 (250 nM, from 9 to 12 months) caused some reduction of retinopathy signs in OXYS rats and did not reveal any negative effects on the control Wistar rat's retina. Prevention of premature retinopathy by SkQ1 was connected with an increase of VEGF mRNA and protein in OXYS rat's retina up to the levels corresponding to the Wistar rats, and did not involve changes in PEDF expression. In contrast the treatment with SkQ1 drops caused a decrease of VEGF mRNA and protein levels and an increase in the PEDF mRNA level in the middle-aged OXYS rats, but in Wistar rats the changes of gene expression were the opposite. CONCLUSIONS: The beneficial effects of SkQ1 on retinopathy connected with normalization of expression of VEGF and PEDF in the retina of OXYS rats and depended on age of the animals and the stage of retinopathy.     

Probability based approach for predicting the course of disease in diabetic retinopathy patients

The number of Diabetes patients has risen in both the developing and the developed nations. It is associated with lot complications retinopathy, nephropathy, neuropathy etc. Diabetic retinopathy is one of the leading causes of preventable blindness. Diabetic patients have to be monitored at regular intervals to detect any signs of retinopathy and deterioration of vision and timely intervention. This requires lot of time and cost both on the part of the patient and the specialist. Therefore there is a need to differentiate the ' high risk ' patients from the ' low risk ' patients, so that the high risk ones can be managed more rigorously while the low risk patients can be referred for less frequent screenings and checkups. Data of around 100 patients with Grade 1 retinopathy was collected. Their physiological parameters with their DR grading after 3 years was recorded. Physiological parameters which were having a higher impact on the course of Retinopathy were taken (e.g. Mild blood urea, Hypertension and Smoking in this case). Transition probabilities of going from one stage to other were calculated. Probability of having a single physiological parameter in a given stage of DR at a given point of time was calculated. Probability of various combinations of these physiological parameters in a given stage of disease was calculated. Then by knowing the present stage of that disease future stage (3 years later in this case) of the disease can be predicted. Based on these predictions, the ' high risk ' patients are differentiated from the ' low risk ' patients and are accordingly referred for screenings and interventions.     

Role of histone modification and DNA methylation in signaling pathways involved in diabetic retinopathy

Retinopathy, characterized by an alteration of the retinal microvasculature, is a common complication of diabetes mellitus. These changes can cause increased permeability and alter endothelial cell proliferation, edema, and abnormal neovascularization and eventually result in blindness. The pathogenesis of diabetic retinopathy (DR) is complicated, involving many factors/mediators such as genetic susceptibility, microRNAs, and cytokines. One of the factors involved in DR pathogenesis is epigenetic changes that can have a key role in the regulation of gene expression; these include microRNAs, histone modifications, and methylation of DNA. The main epigenetic modifications are DNA methylation and posttranslational modifications of the histones. Generally, the studies on epigenetics can provide new opportunities to investigate the molecular basis of diseases with complicated pathogenesis, including DR, and provide essential insights into the potential design of strategies for its treatment. The aim of this study is an investigation of DR pathogenesis and epigenetic modifications that involve in DR development.     

Detection of Neovascularization Based on Fractal and Texture Analysis with Interaction Effects in Diabetic Retinopathy

Diabetic retinopathy is a major cause of blindness. Proliferative diabetic retinopathy is a result of severe vascular complication and is visible as neovascularization of the retina. Automatic detection of such new vessels would be useful for the severity grading of diabetic retinopathy, and it is an important part of screening process to identify those who may require immediate treatment for their diabetic retinopathy. We proposed a novel new vessels detection method including statistical texture analysis (STA), high order spectrum analysis (HOS), fractal analysis (FA), and most importantly we have shown that by incorporating their associated interactions the accuracy of new vessels detection can be greatly improved. To assess its performance, the sensitivity, specificity and accuracy (AUC) are obtained. They are 96.3%, 99.1% and 98.5% (99.3%), respectively. It is found that the proposed method can improve the accuracy of new vessels detection significantly over previous methods. The algorithm can be automated and is valuable to detect relatively severe cases of diabetic retinopathy among diabetes patients.     

Eph-Ephrin双向信号转导途径在眼部血管新生中的作用

Eph/Ephrin家族是受体酪氨酸激酶家族中的最大亚族,在生理和病理性血管形成中起重要作用。眼部血管生成是糖尿病视网膜病、早产儿视网膜等眼部疾病致盲的重要因素,Eph和Ephrin基因在上述眼部疾病中有不同程度表达改变。Eph受体及其配体Ephrin之间的双向信号机制是Eph-Ephrin发挥功能的主要方式。本文就Eph-Ephrin双向信号机制在眼部血管新生中的作用进行综述。