Community Ophthalmology










CHAPTER 28 Community Ophthalmology


Community ophthalmology is described as a new discipline in medicine, promoting eye health and blindness prevention through programs utilizing methodologies of public health, community medicine and ophthalmology.


It is the application of the knowledge of ophthalmology for the benefit of the community and the study of how ophthalmic speciality care can reach the last person in the community.


Importance of Community Ophthalmology


Community ophthalmology is beneficial for the community due to:


Out reach at mass level.


Treatment in remote areas.


Screening of patients who are other wise missed and at times may land up into blindness.


Health education and health system strengthening


Early diagnosis and treatment of eye ailments e.g. school eye camps for refractive error, squint.


Blindness from birth or early childhood has unique problems. The branch of community ophthalmology deals with combating the blindness. It utilizes the ophthalmic knowledge to protect/promote ocular health, methodologies of public health, and community medicine to prevent blindness at the community level.


Prevention of blindness needs ample knowing and understanding of various aspects like:


Definition of blindness.


Magnitude of blindness.


Causes of blindness.


Control of blindness.


Definition of Blindness (OP9.4)


According to WHO, a person having visual acuity of less than 3/60 with correcting glasses in the better eye in day light is defined as blind. A concentric contraction of visual field to an average radius of 10 degree is considered equally disabling. Patients with visual field less than 10° are also considered blind.


Categories of Visual Impairment (OP9.4)


The visual impairment varies and may range from mild to severe. According to WHO, visual impairment can be classified as given in Table 28.1.


Magnitude of Blindness (OP9.4)


Geographic Distribution of Blindness


The problem of blindness is a worldwide phenomenon. Developing countries have more than 90% of all the blind and visually disabled people in the world because people in developing countries are deprived of adequate healthcare to prevent blindness (Table 28.2). On the other hand, in developed countries (Europe and North America), effective measures are taken to prevent blindness and eliminate the “avoidable” blindness (“preventable” and “curable” blindness).


Causes of Blindness


According to WHO, the six major causes of blindness are:


Cataract.


Glaucoma.


Diabetic retinopathy.


Trachoma.


Vitamin A deficiency.


Onchocerciasis.


The estimated number of blinds (%) due to the above causes are as given in Table 28.3.


Cataract, glaucoma, and diabetic retinopathy occur globally and require surgery or laser treatment. These also need an ophthalmologist for treatment. Trachoma, vitamin A deficiency, and onchocerciasis are focal diseases and occur regionally. These can be controlled with the medicine and do not necessarily require an ophthalmologist for treatment.


The causes of blindness in childhood and adults are given below.


Childhood Blindness


Causes of blindness during childhood vary according to the age group, as listed below.


In newborns:


Congenital cataract.


Congenital rubella (intrauterine).


Nystagmus.


Ophthalmia neonatorum.


Retinopathy of prematurity.


In preschool and school-going children:


Vitamin A deficiency.


Measles.


Trauma.


Amblyopia.


Strabismus.


Refractive errors.


The causes of childhood blindness are different in the developed and developing countries too.


In developed countries:


Retinopathy of prematurity.


Congenital cataract.


Congenital malformations.


Nystagmus.


In developing countries:


Corneal scarring.


Vitamin A deficiency.


Congenital cataract.


Ophthalmia neonatorum.


Congenital anomalies.


Adulthood Blindness


The common causes of visual impairments in adults are:


Cataract.


Glaucoma.


High myopia.


Trauma.


Diabetic retinopathy.


Retinal vascular disorders.


Microbial keratitis.


Age related macular degeneration.


Neurological disorders (multiple sclerosis and brain tumors).


AIDS (due to opportunist infections such as cytomegalovirus, herpetic, mycobacterial, fungal, syphilitic, or protozoal retinitis).


Prevention and Control of Blindness (OP9.4)


Measures to control blindness can be planned at various levels and should be based on:


Strategies to control the blindness: It includes the following:


Prevention of the disease before it occurs (primary prevention).


Prevention of visual loss if the disease has occurred (secondary prevention).


Restoration of sight of a blind person (tertiary prevention).


Approach to diseases causing blindness: To restore and maintain good health in the community, the healthcare must include education, control of endemic diseases, good quality of food, water, and clean environment. There must be provision of services for cataract surgery, vitamin A supplementation, control of trachoma, and distribution of ivermectin for onchocerciasis.


Approach to provide services: The services must be organized at the community level (primary eye care services) to promote, prevent, and treat the eye diseases. To make the services effective, education at various levels, adequate referral system and regular refresher training courses for primary care workers must be included. A willing person is selected and trained as a primary care worker. Education is aimed at making the people aware and general information (both environmental and personal) and measure of eye protection at work must be made known to the community.


The primary healthcare worker must be trained regarding the diseases such as ophthalmia neonatorum, trachoma, vitamin A deficiency, etc., who must recognize and treat the diseases. He must recognize and refer immediately for treatment in relation to conditions such as painful red eye with visual loss, cataract, entropion and trichiasis, corneal ulcers, penetrating injuries, vision-affecting pterygium, etc. The activities related to primary healthcare workers in the community must be supervised for a better healthcare delivery.


The secondary eye care services are provided by the general medical practitioners, ophthalmic assistants, or general medical officers trained in eye care. It comprises an adequate infrastructure (instruments and equipment) to handle common blinding conditions and also includes screening for open-angle glaucoma and diabetic retinopathy.


For diseases that need specialized treatment such as corneal grafting, retinal detachment surgery, etc., the patients are referred to large institutes in urban centers which have all the state-of-the-art diagnostic and therapeutic facilities (tertiary eye care services) as well as eye specialists.


In certain countries, a mobile ophthalmic unit (mobile eye services) is formed which conducts eye camps in the periphery and remote rural areas. These mobile ophthalmic units are supported by the government to provide the comprehensive eye care facilities and health education.


A community approach for blindness control: It is directed at the target population at risk and concentrates on increasing awareness, assessment, and management of the disease to prevent the blindness.


Vision 2020: Right to Sight (OP9.4)


It is a global initiative of WHO and IAPB (International Agency for Prevention of Blindness) launched in the year 1999. It is a project to combat the problem of blindness in the world and eliminate the avoidable blindness by the year 2020. It is based on the concept that every living person has a right to sight. It is estimated that one person goes blind every 5 seconds and one child goes blind every minute. Approximately, 80% of global blindness is treatable and/or preventable; to eliminate this unnecessary blindness from the world, WHO and IAPB are working in collaboration with various international nongovernmental organizations (NGOs).


Objectives of Vision 2020


The objective of this global initiative is to eradicate the avoidable blindness by the year 2020 which can be achieved by:


Implementing specific programs to control the major causes of blindness.


Creating adequate eye care facilities in under privileged areas.


Creating well-trained eye care workers.


To implement Right to Sight (Vision 2020), WHO has focused on five main priorities:


Cataract.


Trachoma.


Onchocerciasis.


Childhood blindness.


Refractive errors and low vision.


However, priorities are decided by a country, depending on the specific blinding conditions in that country. The Vision 2020 program was adopted by the government of India, and other diseases of national importance such as glaucoma, diabetic retinopathy, and corneal blindness are also to be tackled as priority.


Prevention and Control of the Causes of Blindness


Cataract


It is the main cause of blindness. The high-prevalence of blindness from cataract in developing countries is due to absence of effective high eye healthcare system and poor surgical care for cataract. Cataract may develop at an earlier age due to exposure to UV rays, X-rays, corticosteroids (oral and topical), malnutrition, and dehydration.


Prevention and Treatment


It includes:


Screening for cataract by health worker and motivation of the affected people to undergo surgery at the primary level.


Cataract surgery must be performed with intraocular lens implantation. There must be provision of facilities for cataract surgery of complicated cases and provision of trained staff at centers.


Trachoma


According to WHO, approximately 150 million people are affected by trachoma worldwide and nearly 6 million people are believed to be blind due to trachoma. Trachoma is potentially a blinding disease seen worldwide but mostly in developing countries. The disease results in more scarring and consequent blinding complications such as entropion and trichiasis with corneal opacity. To prevent visual loss and blindness from the disease, trachoma must be controlled.


The trachoma is associated with poverty, overcrowding, inadequate face-washing, improper sanitation, and nonavailability of clean water. The active trachoma decreases in severity/prevalence in developed countries. In India, blindness due to trachoma is on the decline.


Prevention and Treatment


In developing communities, the SAFE strategy is employed for control of trachoma.


SSurgery (to correct entropion and trichiasis in order to prevent blindness)


AAntibiotic treatment (to reduce the severity of active trachoma, scarring and blinding complications). The effective antibiotics are topical and oral tetracycline, oral erythromycin, and sulphonamides. Oral sulphonamides have too many side effects but oral azithromycin is now recommended as single dose therapy due to its prolonged effect. Tetracycline eye ointment is applied twice daily for 6 weeks in active trachoma.


FFacial cleanliness.


EEnvironmental improvement (access to clean water and sanitation).


WHO established an alliance for the Global Elimination of Trachoma by the end of year 2020 (GET 2020).


Onchocerciasis (River Blindness)


The disease is endemic in Africa, South and Central America, and Yemen. In Africa, the disease is
more severe in countries along the major rivers which lie between 12° north and 15° south of the equator. The black fly (Simulium) is the intermediate host which lays its egg in fast-running water and lives near rivers. About 20 million people are affected with onchocerciasis and 25,000 are blind.


Prevention and Treatment


The goal of the treatment is to eliminate both the adult form and microfilariae from the body. Ivermectin is distributed to the affected population in endemic areas. The community-directed treatment with annual doses of ivermectin (150 µg /kg) is given as a single dose. The target is to develop “National Onchocerciasis Control Program” in endemic areas with the aim
to eliminate the blindness due to onchocerciasis by the year 2020. WHO has sponsored a program to control the fly population and has been successful.


Childhood Blindness


Regional Distribution of Childhood Blindness


Approximately, 1.5 million children suffer from visual impairment and blindness in the world. Out of these, 1 million blind children live in Asia. Table 28.4 shows the global prevalence of childhood blindness.


It is estimated that approximately 500,000 children in the world become blind each year; 50% of the childhood blindness is preventable. The aim of the project is to eliminate avoidable causes of childhood blindness by the year 2020.


Prevention and Treatment


To reduce the childhood blindness population at risk, which vary from place to place, causes of childhood blindness are identified. The eye disorders in children must first be identified by screening programs and then timely intervention must be conducted.


The main causes include Vitamin A deficiency, measles, ophthalmia neonatorum, congenital cataract, and retinopathy of prematurity.


Under the global initiative, Vision 2020 includes:


Vitamin A supplementation.


Immunization against measles and vaccination against rubella in all children at one year of age and in prepubertal girls.


Cleansing the eyes of newborn babies after birth to prevent ophthalmia neonatorum, followed by application of 1% tetracycline eye ointment.


Surgically avoidable causes of childhood blindness such as congenital cataract, glaucoma, and complicated cases of eye trauma are managed.


Screening and treatment of retinopathy of prematurity is performed.


School screening programs for diagnosis and management of common conditions like refractive errors, trachoma in endemic area, and health education in school must be promoted.


Prophylactic vitamin A administration in areas with endemic vitamin A deficiency is as given in Table 28.5.


Refractive Errors and Low Vision (IM24.15)


Refractive errors cause worldwide visual disability. A global initiative to combat refractive errors and low vision is required. Refractive errors are corrected by spectacles to prevent amblyopia, while the patient with low vision needs low-vision devices. The aim is to eliminate visual impairment (visual acuity less than 6/18) and blindness due to refractive errors or other causes of low vision. Refractive errors are on the priority of the Vision 2020 project. Strategies recommended under “Vision 2020” initiative include:


Refractive services and dispensing of glasses.


School eye health programs.


Low vision service centers to be established at 150 tertiary level eye care institutions.


Glaucoma


Approximately, 15% of all blindness is due to glaucoma, whether it is congenital, primary open-angle, primary angle-closure, or secondary glaucoma. Primary open-angle is more common. Glaucoma is an important cause of blindness in developed and developing countries. It is estimated that nearly 600,000 people per year go blind from glaucoma globally. Vision loss due to glaucoma cannot be recovered, so to prevent blindness from this disease, early detection and proper treatment is important. The risk factors determined by epidemiological studies include age, intraocular pressure (IOP), positive family history, diabetes, hypertension, myopia, smoking, and alcohol intake.


Prevention and Treatment


A glaucoma scanning program is recommended for early detection and treatment of glaucoma which include tonometry and fundus examination. Visual field examination is conducted in persons with elevated IOP or fundus changes. Compared with open-angle glaucoma, acute angle-closure glaucoma is easier to diagnose. The primary healthcare workers must be trained to recognize acute red eye with pain, decreased vision, and dilated pupil, so that they immediately refer to a higher center. The patients at risk should be tested periodically by a qualified ophthalmologist.


Diabetic Retinopathy


It is a leading cause of blindness in adults both in developed and developing countries. To prevent visual loss from diabetic retinopathy, a periodic follow-up is very important because lost vision due to diabetic retinopathy cannot be recovered. It is uncommon in patients with duration of less than 10 years of diabetes but common after 20 years of diabetes.


Prevention and Treatment


It includes:


Regular screening.


Awareness by health workers.


Referral to eye surgeon.


Fundus fluorescein angiography and laser photocoagulation.


Changes in lifestyle of individuals at risk.


Corneal Blindness


Corneal diseases are the leading cause of visual impairment. The major causes of corneal blindness are corneal ulcers which may be secondary to infections, injuries, and nutritional deficiencies. Microbial keratitis mostly affects agriculture workers in developing countries.


Prevention and Treatment


To reduce the prevalence of corneal blindness, the strategies include:


Protective measures include use of goggles.


Prevention and control of vitamin A deficiency to prevent xerophthalmia.


Education of people regarding avoidance of ocular trauma.


Health education and improvement in personal hygiene to reduce eye infections.


Promotion of eye donation and establishment of eye banks.


Keratoplasty to restore vision in cases of corneal blindness.


National Program for Control of Blindness in India (OP9.4)


The national program for control of blindness (NPCB) was launched by the government of India in the year 1976 as a 100% centrally sponsored program with the goal of reducing the prevalence of blindness from 1.4 to 0.3% by the year 2000. However, due to constraints at various levels, the target could not be achieved. As per a survey in 2001–02, prevalence of blindness was estimated to be 1.1%, which reduced to 1% in 2006–07, as per another survey on avoidable blindness conducted under NPCB. Therefore, NPCB set the objective to reduce the prevalence of blindness by the year 2020.


Later this was merged with vision 2020 program with a target to achieve blindness prevalence 0.3% by 2020. Currently 13th plan (2017–2020) is going on which has been renamed as “National program for control of blindness and visual impairment (NPCBVI)”. Now part of funding is shared by states as well.


Objectives of NPCBVI


To reduce the backlog of blindness through identification and treatment of the blind.


To provide comprehensive eye care services.


To improve quality service delivery to the affected population.


To develop human resources for eye care.


To enhance community awareness on eye care.


To secure participation of voluntary organizations and private practitioners in eye care.


To provide best possible treatment for curable blindness available in the district/region.


To set up the mechanism for referral coordination and feedback between organizations dedicated to prevention, treatment and rehabilitation.


Strategies to Achieve the Objectives


The implementation of the program was decentralized with the formation of the State Health Society (blindness division) and District Health Society (DHS) in each district of the country.


State Health Society


Purpose


The purpose of state health society is to plan, implement, and monitor blindness control activities in all the districts of the state.


Functions


To coordinate and monitor with all the district health societies.


To receive and monitor the use of funds for equipment and material from the government.


Repair and renovation of existing equipment.


To secure participation of voluntary organizations and private practitioners in eye care.


To promote eye donation through various media and monitor the districts for collection and utilization of eyes collected by eye banks.


DHS


Composition


It has a maximum of 15 members, consisting of not more than 8 ex-officio and seven other members as follows:


Chairman: District magistrate


Vice chairman: Chief medical officer/district health officer.


Member secretary: Officer of the level of deputy CMO (preferably an ophthalmologist), may be designated as District Program Manager (DPM), who would also be the member secretary of the society.


Technical advisor: Chief ophthalmic surgeon of district hospital. If medical college is located in the district, then Head of Department (HOD) of ophthalmology may be designated as technical advisor to the society.


Members: Medical superintendent/civil surgeon of district hospital


District education officer


President local IMA branch


Representatives from NGOs engaged in eye care services.


Prominent practicing eye surgeons.


The membership of nonofficials should be for one year only and renewable as per the general body decisions for a further period. The ex-officio members shall be members as long as they hold the office.


Functions


The primary purpose of DHS is to plan, implement, and monitor blindness control activities in the district. The important functions of the DHS are:


To assess the magnitude and spread of blindness village-wise in the district.


Reduction in the backlog of blind persons– It is achieved by screening of population above 50 years, organizing screening eye camps, and transporting the operable cases.


To train community level workers and ophthalmic assistants/nurses involved in eye care services.


To receive and monitor use of funds, equipment, and materials.


Screening of school age group children to identify and treat the refractive errors especially in underserved areas.


To promote eye donation through various media, and monitor the districts for collection and utilization of eyes collected by eye banks.


Public awareness to prevent and treat the eye diseases.


To involve voluntary and private hospitals.


Development of mobile ophthalmic units in the district level for screening and transportation of patients.


Establishment of vision centers in all PHCs.


The NPCB funds are released by the government of India to the state blindness control society, or state health and family welfare society, based on the annual action plan submitted. India has received technical and financial assistance from World Bank, WHO, DANIDA (Danish International Development Agency), and other international NGOs to control blindness in the country, but currently the program is not dependent on any external funding.


Achievements of NPCB


Higher success rates following cataract surgery with intraocular lens (IOL) implantation as compared with conventional surgery. There has been a significant increase in cataract surgery with IOL implantation from <9% in 1994 to 93% in 2006–07.


307 dedicated eye operation theaters and eye wards built in district level hospitals.


More than 2000 eye surgeons trained in eye surgery and other super specialties.


Supply of ophthalmic equipment for diagnosis and treatment of common eye disorders.


Training of teachers, screening of school children, and distribution of free glass in children with refractive errors under school eye screening programs during the year 2009–2010.


New Initiatives (Proposed) during 11th Five Year Plan (2007–2012)


Under the program, the following new initiatives are proposed:


Construction of dedicated eye wards and eye operation theaters in district and subdistrict hospitals.


Appointment of ophthalmic surgeons and ophthalmic assistant in new district and subdistrict hospitals.


Appointment of ophthalmic assistants in PHCs/vision centers.


Appointment of eye donation counsellors.


Development of mobile ophthalmic units.


Special attention to clear cataract backlog.


Telemedicine in ophthalmology (eye care management information and communication network).


Involvement of private practitioners in subdistrict, blocks, and village level.


A provision of Rs 1550 crore has been proposed for implementation of NPCB during the 11th five-year plan.


Initiative during 12th Five Year Plan (NPCB) (2013–2018)


Goals


To reduce the prevalence of blindness to less than 0.3%.


To establish infrastructure and efficiency levels in the program to be able to cater to new cases of blindness each year in order to prevent future backlog.


Objectives


To reduce the backlog of blindness through identification and treatment of blind at primary, secondary, and tertiary levels, based on assessment of the overall burden of visual impairment in the country.


Develop and strengthen the strategy of NPCB for “eye health” and prevention of visual impairment through provision of comprehensive eye care services and quality service delivery.


Strengthening and upgradation of RIOs to become centers of excellence in various subspecialities of ophthalmology.


Strengthening the existing and developing additional human resources and infrastructure facilities for providing high-quality comprehensive eye care in all districts of the country.


To enhance community awareness on eye care and lay stress on preventive measures.


Increase and expand research for prevention of blindness and visual impairment.


To secure participation of voluntary organizations/private practitioners in eye care.


Proposed NPCBVI Plan for Next 5 Years


To clear backlog of cataract blindness.


Emphasis on quality of surgery.


Main focus is upon- free cataract surgery, school eye screening, keratoplasties.


In an endeavor to enhance its action plan to hit the blindness, government of India encourages participation by non-government organizations (NGOs) by offering financial support (Grant-in-aid) to meet out expenses incurred. Grant-in-aid is given in Table 28.6.


Categorization of visual disability: The persons with visual disability get some government privileges. A categorization of visual disability for that purpose is required which is done by a board with specialists at district hospitals. Fig. 28.1 is used to know the percentage of visual disability.


























Table 28.1 Visual impairment as per WHO


Category of visual impairment


Best corrected visual acuity in the better eye


Normal vision


6/6 to 6/18


Moderate visual impairment (low vision)


Less than 6/18 to 6/60 (i.e., cannot see 6/18)


Severe visual impairment (low vision)


Less than 6/60 to 3/60 (i.e., cannot see 6/60)


Blindness


Less than 3/60 to 1/60 (i.e., cannot see 3/60) or


Visual field <10° but >5° (i.e., between 5°–10°)


<1/60 to only light perception (i.e., cannot see 3/60)
or visual field <5°.


No light perception


Abbreviation: WHO, World Health Organisation.

































Table 28.2 Statistics of blindness


Cause of blindness


Number of people (in millions)


Blindness due to eye disease


37


Blindness due to refractive errors


08


(A) Total blindness due to all causes


45


Low vision due to eye diseases


124


Low vision due to refractive errors


145


(B) Total visual impairment due to all causes


269


Total visual impairment (A + B)


314 (45 + 269)






























Table 28.3 Global data on etiology of blindness


Cause of blindness


Percentage of blinds


Cataract


43%


Glaucoma


15%


Diabetic retinopathy


8%


Trachoma


11%


Vitamin A deficiency


6%


Onchocerciasis


1%

































Table 28.4 Global prevalence of childhood blindness


Region


Prevalence per 1000 children


Estimated no. of blind children


Africa


1.1


2,64,000


Asia


0.9


1,080,000


South and Central America


0.6


78,000


Europe, Japan and USA


0.3


72,000


Total



1,494,000





















Table 28.5 Prophylactic vitamin A administration


In infants 6–12 months


100,000 IU of vitamin A orally every 3–6 months.


In children 1–6 years


200,000 IU of vitamin A orally every 3–6 months.


Lactating mothers


200,000 IU of vitamin A orally once a delivery or during the first 8 weeks after delivery if breast feeding.


Infants <6 months not on breast feeding


50,000 IU of vitamin A orally as a single dose.















































































Table 28.6 NPCVI grants-in-aid: recurring



Recurring grant per unit


Cataract surgery


NGO: Rs 2000



NGO/Pvt using govt.



OT: Rs 1200



Govt.: Rs 1000


Diabetic retinopathy


Rs 2000


Childhood blindness


Rs 2000


Glaucoma


Rs 2000


Keratoplasty


Rs 7500


Vitreoretinal surgery


Rs 10000


Spectacles


Rs 350/pair of spectacles


Cornea collection


Eye bank: Rs 2000



Collection centre: Rs 1000


Information


Large states: Rs 20 lakh


Education


Small states: Rs 10 lakh


Communication


NPCBVI grants-in-aid: Non-recurring



Non-ecurring grant/unit


District hospital


Rs 40 lakh


Sub-district hospital


Rs 20 lakh


Vision centre/PHC for govt./NGO


Rs 01 lakh


Eye bank


Rs 40 lakh


Eye donation centres


Rs 01 lakh


Multipurpose district mobile ophthalmic units


Rs 30 lakh


Fixed Tele-ophthalmology network


Rs 25 lakh


Abbreviations: PHC, primary health care; NGO, non-government organization.




Fig. 28.1 Categorization of visual disability.

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Nov 20, 2022 | Posted by in OPHTHALMOLOGY | Comments Off on Community Ophthalmology

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