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1.  Characteristics of 681 Low Vision Patients in Korea 
Journal of Korean Medical Science  2010;25(8):1217-1221.
The purpose of our study was to evaluate the characteristics and the changes of low vision patients over ten years in Korea, and to establish useful data for planning low vision services, active care and rehabilitation. We conducted a retrospective study of 681 low vision patients who visited two low vision clinics in Seoul from 1995 to 2008. Age and sex distribution, cause of low vision, type of prescribed low vision aids, and changes of the characteristics were reviewed. In result, male were more than female. The age group between 11 and 20-yr-old (18.1%) was the largest age group. Optic atrophy (28.3%) was main causes of low vision. However, elderly low vision patients is increasing and macular degeneration is becoming a leading cause of low vision (P<0.05). One thousand five low vision aids (LVAs) were prescribed for 681 patients (1.46±0.62 aids for each patient). Near LVAs were prescribed more than distance LVAs. In most patients, the use of LVAs improved both near and distance visual function. This study is the first survey of a large number of low vision patients over a ten year period in Korea. On the base of this study, the planning of low vision services and more active rehabilitation for low vision patients, especially elderly patients, need in Korea.
PMCID: PMC2908794  PMID: 20676336
Low Vision; Rehabilitation; Visual Function
2.  Prevalence and determinants of age-related macular degeneration in the 50 years and older population: A hospital based study in Maharashtra, India 
Indian Journal of Ophthalmology  2013;61(5):196-201.
We present the magnitude and determinants of age-related macular degeneration (ARMD) among the 50 year and older population that visited our hospital.
Materials and Methods:
This was a cohort of eye patients with ARMD, seen from 2006 to 2009. Optometrist noted the best-corrected vision. Ophthalmologists examined eyes using a slit-lamp bio-microscope. The ARMD was confirmed by fluoresceine angiography and optical coherent tomography. The age, sex, history of smoking, sun exposure, family history of ARMD, diet, body mass index (BMI), hypertension, and diabetes were associated with ARMD.
Of the 19,140 persons of ≥ 50 years of age-attending eye clinic in our hospital, 302 persons had ARMD in at least one eye. The proportion of overall ARMD was 1.38% (95% CI 1.21--1.55). The proportion of age-related maculopathy (ARM) and late ARMD was 1.14% (95% CI 0.99--1.29) and 0.24% (95% CI 0.21–0.24) respectively. ARM was unilateral and bilateral in 64 (29.2%) and 155 (70.8%) persons respectively. Dry ARMD was found in 47.8%. On regression analysis, old age (OR = 1.05), male (OR = 0.54), and history of smoking (OR = 2.32) were significant risk factors of ARMD. A total of 4.2% of persons with ARMD were blind (vision <3/60). Only 43% of persons with ARMD had J6 grade of the best-corrected near vision.
ARMD does not seem to be of public health magnitude in the study area. Early stages of ARMD were common among patients. ge, being male, and history of smoking were significant risk factors for ARMD.
PMCID: PMC3730501  PMID: 23571245
Age-related macular degeneration; blindness; low vision; prevalence; retina
3.  Couching Techniques for Cataract Treatment in Osogbo, South West Nigeria 
Ghana Medical Journal  2013;47(2):64-69.
Couching is still being practised in developing countries including Nigeria despite its adverse effects on vision.
To find out the different techniques of couching, highlight the unacceptable poor visual sequelae and assess knowledge, attitudes, and practices of subjects.
Settings and Design
Clinic based and prospective observational study.
Methods and Material
Structured interview and clinical examination of consecutive patients was used to obtain information.
Fifteen subjects and 20 eyes of 9(60%) males and 6(40%) females were studied. Age range 60 –90 years and mean 72.4±8.0. Commonest presenting complaints were “I cannot see properly/clearly” 4(26.7%) and “I want to do my second eye so I can see better” 3(20%). Presenting Versus (vs.) Corrected visual acuity (VA) was75% vs 60% blind, 55% vs 45% low vision, and 0% vs 10% normal vision, p= 0.032. Friends and neighbours mostly introduced subjects to couching (26.7% each). Commonest methods involved using sharp objects/needling 45% and blunt/grooving/rocking methods (30%). Subjects assumed “supine” position 75% of time. Eighty five percent of eyes were done at the coucher's. Procedure was painful in 73.3%. Only 5 eyes (25%) maintained vision for >10years. Thirteen (86.7%) said “no” to a repeat procedure and 93.4% would advice against couching.
Couching methods used were very crude and archaic with attendant poor quality of vision and dissatisfaction. Public education, affordable and accessible cataract surgical services taken to the rural communities could gradually phase out couching.
PMCID: PMC3743109  PMID: 23966741
Couching; Methods; Visual sequelae; Nigeria
4.  Prevalence and Causes of Blindness and Low Vision in Southern Sudan  
PLoS Medicine  2006;3(12):e477.
Blindness and low vision are thought to be common in southern Sudan. However, the magnitude and geographical distribution are largely unknown. We aimed to estimate the prevalence of blindness and low vision, identify the main causes of blindness and low vision, and estimate targets for blindness prevention programs in Mankien payam (district), southern Sudan.
Methods and Findings
A cross-sectional survey of the population aged 5 y and above was conducted in May 2005 using a two-stage cluster random sampling with probability proportional to size. The Snellen E chart was used to test visual acuity, and participants also underwent basic eye examination. Vision status was defined using World Health Organization categories of visual impairment based on presenting visual acuity (VA). A total of 2,954 persons were enumerated and 2,499 (84.6%) examined. Prevalence of blindness (presenting VA of less than 3/60 in the better eye) was 4.1% (95% confidence interval [CI], 3.4–4.8); prevalence of low vision (presenting VA of at least 3/60 but less than 18/60 in the better eye) was 7.7% (95% CI, 6.7–8.7); whereas prevalence of monocular visual impairment (presenting VA of at least 18/60 in better eye and VA of less than 18/60 in other eye) was 4.4% (95% CI, 3.6–5.3). The main causes of blindness were considered to be cataract (41.2%) and trachoma (35.3%), whereas low vision was mainly caused by trachoma (58.1%) and cataract (29.3%). It is estimated that in Mankien payam 1,154 persons aged 5 y and above (lower and upper bounds = 782–1,799) are blind, and 2,291 persons (lower and upper bounds = 1,820–2,898) have low vision.
Blindness is a serious public health problem in Mankien, and there is urgent need to implement comprehensive blindness prevention programs. Further surveys are essential to confirm these tragic findings and estimate prevalence of blindness and low vision in the entire region of southern Sudan in order to facilitate planning of VISION 2020 objectives.
A cross-sectional survey using two-stage cluster random sampling was conducted in Mankien district, southern Sudan. The prevalence of blindness (4.1%) and of low vision (7.7%) were much higher than expected.
Editors' Summary
Blindness is very common. The World Health Organization says that around 161 million people have at least some degree of “visual impairment,” of whom 37 million are blind. There are many causes of blindness, including infections, malnutrition, injury, and aging. Around 90% of blind people live in developing countries. It is estimated that 75% of the cases of blindness in these countries could have been prevented but, in situations where people are poor and live in remote locations, both prevention and treatment efforts are extremely difficult. In times of war and civil conflict, the problems become even more severe. In these situations, it is very hard even to get an idea of the number of people who are blind. Surveys to find this out are important as a first step toward providing prevention and treatment services. Surveys play an essential part in international efforts to fight blindness.
Why Was This Study Done?
Sudan is the largest country in Africa and one of the poorest in the world. Southern Sudan has spent most of the last five decades in a state of civil war and is a very remote region. The last information collected on the scale of the blindness problem was in the early 1980s. The researchers decided to conduct a survey in Mankien—a district of Sudan with a total population that is estimated to be around 50,000. Their aim was to estimate how many people were blind or had “low vision” and to find out the main causes of blindness. This would be useful in planning a blindness prevention programme for the district. It would also give some idea of the situation in the southern Sudan as a whole.
What Did the Researchers Do and Find?
Working under very difficult conditions, the researchers selected villages to be visited at random. A house in each village visited was selected by spinning a pen in the middle of the village. The people in this house were examined and then other houses were chosen, also at random. In total, 2499 people were examined. Children under five years were not included in survey.
A very high rate of blindness was found—4%. This is more than twice the level that would be expected, given what is known about the prevalence of blindness in other parts of rural Africa. The two most common causes of blindness and low vision were cataract and trachoma, each accounting for over one-third of cases. Cataract is mainly a disease of older people; the lens of the eye becomes opaque. Trachoma is caused by an infection; it is the subject of another article by the same researchers in this issue of PLoS Medicine. Trachoma was responsible for a greater proportion of cases of blindness than has been found in studies in other parts of rural Africa.
What Do These Findings Mean?
Based on the researchers' use of the random walk survey technique, the prevalence of blindness in this district and possibly the rest of southern Sudan appears to be extremely serious. The number of cases caused by trachoma is especially worrying. This information will help efforts to improve the situation. The implications of the study—and a discussion of the methods the researchers used—will be found in two “Perspective” articles in this issue of PLoS Medicine (by Buchan and by Kuper and Gilbert).
Additional Information.
Please access these Web sites via the online version of this summary at
General information about blindness is available on Wikipedia, an internet encyclopedia that anyone can edit
Vision 2020 is a major international initiative to reduce blindness, in which many organizations collaborate
The World Health Organization has a Web page on blindness
Many charities provide help to blind people in developing countries, for example: Sight Savers, Lions Clubs International Foundation, Dark and Light Blind Care
A profile of Sudan will be found on the website of the BBC
PMCID: PMC1702554  PMID: 17177596
5.  Prevalence of Age-Related Macular Degeneration in Nakuru, Kenya: A Cross-Sectional Population-Based Study 
PLoS Medicine  2013;10(2):e1001393.
Using digital retinal photography and slit lamp examination in a population-based sample in the Nakuru District of Kenya, Andrew Bastawrous and colleagues determined the prevalence of age-related macular degeneration in adults 50 years and older.
Diseases of the posterior segment of the eye, including age-related macular degeneration (AMD), have recently been recognised as the leading or second leading cause of blindness in several African countries. However, prevalence of AMD alone has not been assessed. We hypothesized that AMD is an important cause of visual impairment among elderly people in Nakuru, Kenya, and therefore sought to assess the prevalence and predictors of AMD in a diverse adult Kenyan population.
Methods and Findings
In a population-based cross-sectional survey in the Nakuru District of Kenya, 100 clusters of 50 people 50 y of age or older were selected by probability-proportional-to-size sampling between 26 January 2007 and 11 November 2008. Households within clusters were selected through compact segment sampling.
All participants underwent a standardised interview and comprehensive eye examination, including dilated slit lamp examination by an ophthalmologist and digital retinal photography. Images were graded for the presence and severity of AMD lesions following a modified version of the International Classification and Grading System for Age-Related Maculopathy. Comparison was made between slit lamp biomicroscopy (SLB) and photographic grading.
Of 4,381 participants, fundus photographs were gradable for 3,304 persons (75.4%), and SLB was completed for 4,312 (98%). Early and late AMD prevalence were 11.2% and 1.2%, respectively, among participants graded on images. Prevalence of AMD by SLB was 6.7% and 0.7% for early and late AMD, respectively. SLB underdiagnosed AMD relative to photographic grading by a factor of 1.7.
After controlling for age, women had a higher prevalence of early AMD than men (odds ratio 1.5; 95% CI, 1.2–1.9). Overall prevalence rose significantly with each decade of age. We estimate that, in Kenya, 283,900 to 362,800 people 50 y and older have early AMD and 25,200 to 50,500 have late AMD, based on population estimates in 2007.
AMD is an important cause of visual impairment and blindness in Kenya. Greater availability of low vision services and ophthalmologist training in diagnosis and treatment of AMD would be appropriate next steps.
Please see later in the article for the Editors' Summary
Editors' Summary
Worldwide, 39 million people are blind, and 246 million people (mainly living in developing countries) have moderate or severe visual impairment. The third leading global cause of blindness (after cataracts and glaucoma) is age-related macular degeneration (AMD). This group of conditions is characterized by lesions in the macular (central) region of the retina, the tissue at the back of the eye that converts light into electrical messages and sends them to the brain. AMD, which affects older people, destroys the sharp central vision that is needed for reading or driving, leaving only dim, blurred images or a black hole at the center of vision. AMD can be diagnosed by examining digital photographs of the retina or by examining the retina directly using a special magnifying lens (slit lamp biomicroscopy). There is no cure for AMD, although injections into the eye of certain drugs, such as bevacizumab, that block the activity of vascular endothelial growth factor can slow the rate of vision loss caused by some forms of AMD.
Why Was This Study Done?
Most investigations of the prevalence (the proportion of a population with a disease) of AMD and of risk factors for AMD have studied people with European or Asian ancestry. Very little is known about AMD in African populations, and the data that are available mainly come from African populations living outside Africa. It is important to know whether AMD is an important cause of visual impairment and blindness in Africa, so that informed decisions can be made about the need for AMD programs in African countries. In this cross-sectional population-based study, the researchers investigate the prevalence of AMD among people aged 50 years or older living in Nakuru District (an ethnically diverse region of Kenya) and look for predictors of AMD in this population. In a cross-sectional population-based study, researchers observe a representative subset of a population at a single time point.
What Did the Researchers Do and Find?
The researchers randomly selected 100 clusters of 50 people aged 50 years or older for their study. Between January 2007 and November 2008, study participants had a comprehensive eye examination and completed a standardized interview that included questions about their age, gender, other demographic details, medical history, and exposure to possible risk factors for AMD. Based on digital retinal images, the prevalences of early and late AMD among the study population were 11.2% and 1.2%, respectively. The prevalences of early and late AMD judged by slit lamp biomicroscopy were 6.7% and 0.7%, respectively. After controlling for age, women had a higher prevalence of both early and late AMD than men. The overall prevalence of AMD rose with age: compared to the youngest age group, the oldest age group had a three-fold higher risk of developing late AMD. Of the people with any grade of AMD, 25.6% had some visual impairment and 2.5% were blind. Overall, 9.9% of the blindness seen in the study was attributable to AMD.
What Do These Findings Mean?
These findings identify AMD as an important cause of visual impairment and blindness in Nakuru District, Kenya. Extrapolation of these findings to the whole of Kenya suggests that 283,900 to 362,800 Kenyans had early AMD and 25,200 to 50,500 had late AMD in 2007. The accuracy of these findings is limited by the inability to obtain digital retinal images from all the participants (often because of electricity failures) and by other aspects of the study design. Moreover, because the methodology used in this study differed from some other studies of AMD, the prevalence of AMD reported here cannot be compared directly to those found in other studies. Nevertheless, these findings have several important implications. In particular, although recent evidence suggests that bevacizumab is likely to be both effective and affordable in Africa, the infrastructure required to deliver an adequate AMD service is currently prohibitively expensive in most African countries. Thus, these findings suggest that it is essential that research is undertaken to support the development of AMD treatment programs that are affordable and deliverable in Africa, and that low vision resources are provided for individuals with vision impairment.
Additional Information
Please access these websites via the online version of this summary at
The US National Eye Institute provides detailed information about age-related macular degeneration
The UK National Health Service Choices website also provides information about age-related macular degeneration, including personal stories about the condition
The UK Royal National Institute of Blind People has information on age-related macular degeneration, including a video of a person describing their experiences of the condition
AMD Alliance International provides written and audio information in several languages about age-related macular degeneration, including a large selection of personal stories; the Macular Degeneration Partnership also provides information about age-related macular degeneration, including a simulation of the condition
MedlinePlus has links to additional resources about age-related macular degeneration (in English and Spanish)
PMCID: PMC3576379  PMID: 23431274
6.  Low vision in east African blind school students: need for optical low vision services. 
AIMS--There is increasing awareness of the needs of children with low vision, particularly in developing countries where programmes of integrated education are being developed. However, appropriate low vision services are usually not available or affordable. The aims of this study were, firstly, to assess the need for spectacles and optical low vision devices in students with low vision in schools for the blind in Kenya and Uganda; secondly, to evaluate inexpensive locally produced low vision devices; and, finally, to evaluate simple methods of identifying those low vision students who could read N5 to N8 print after low vision assessment. METHODS--A total of 230 students were examined (51 school and 16 university students in Uganda and 163 students in Kenya, aged 5-22 years), 147 of whom had a visual acuity of less than 6/18 to perception of light in the better eye at presentation. After refraction seven of the 147 achieved 6/18 or better. Eighty two (58.6%) of the 140 students with low vision (corrected visual acuity in the better eye of less than 6/18 to light perception) had refractive errors of more than 2 dioptres in the better eye, and 38 (27.1%) had more than 2 dioptres of astigmatism. RESULTS--Forty six per cent of students with low vision (n = 64) could read N5-N8 print unaided or with spectacles, as could a further 33% (n = 46) with low vision devices. Low vision devices were indicated in a total of 50 students (35.7%). The locally manufactured devices could meet two thirds of the need. CONCLUSION--A corrected distance acuity of 1/60 or better had a sensitivity of 99.1% and a specificity of 56.7% in predicting the ability to discern N8 print or better. The ability to perform at least two of the three simple tests of functional vision had a sensitivity of 95.5% and a specificity of 63.3% in identifying the students able to discern N8 or better.
PMCID: PMC505266  PMID: 7488599
7.  Visual Impairment Secondary to Congenital Glaucoma in Children: Visual Responses, Optical Correction and Use of Low Vision Aids 
Clinics (Sao Paulo, Brazil)  2009;64(8):725-730.
Congenital glaucoma is frequently associated with visual impairment due to optic nerve damage, corneal opacities, cataracts and amblyopia. Poor vision in childhood is related to global developmental problems, and referral to vision habilitation/rehabilitation services should be without delay to promote efficient management of the impaired vision.
To analyze data concerning visual response, the use of optical correction and prescribed low vision aids in a population of children with congenital glaucoma.
The authors analyzed data from 100 children with congenital glaucoma to assess best corrected visual acuity, prescribed optical correction and low vision aids.
Fifty-five percent of the sample were male, 43% female. The mean age was 6.3 years. Two percent presented normal visual acuity levels, 29% mild visual impairment, 28% moderate visual impairment, 15% severe visual impairment, 11% profound visual impairment, and 15% near blindness. Sixty-eight percent received optical correction for refractive errors. Optical low vision aids were adopted for distance vision in 34% of the patients and for near vision in 6%. A manual monocular telescopic system with 2.8 × magnification was the most frequently prescribed low vision aid for distance, and for near vision a +38 diopter illuminated stand magnifier was most frequently prescribed.
Careful low vision assessment and the appropriate prescription of optical corrections and low vision aids are mandatory in children with congenital glaucoma, since this will assist their global development, improving efficiency in daily life activities and promoting social and educational inclusion.
PMCID: PMC2728183  PMID: 19690654
Blindness; Glaucoma; Low Vision; Rehabilitation; Refractive Errors
8.  Vision in albinism. 
PURPOSE: The purpose of this investigation was to study vision in albinism from 3 perspectives: first, to determine the characteristics of grating acuity development in children with albinism; second, to study the effect of illumination on grating acuity; and third, to define the effect of melanin pigment in the macula on visual acuity. METHODS: I. Binocular and monocular grating acuity was measured with the acuity card procedure in 40 children with albinism during the first 3 years of life. Recognition acuity was eventually measured in 27 of these patients. Ocular pigment was documented by a previously established method of grading iris transillumination and macular transparency. II. Grating acuity under standard and increased illumination levels was measured in 20 adults with albinism (group I) compared with that in 20 adults with nystagmus due to conditions other than albinism (group II) and 20 adults without ocular abnormalities (group III). Recognition acuity measured with the ETDRS charts was also recorded for each group. III. Best-corrected binocular acuity was measured in 29 patients with albinism who were identified with melanin pigment in their maculas by direct ophthalmoscopy. RESULTS: I. Both binocular and monocular grating acuity was reduced 2 to 3 octaves below the norm for ages 6 months to 3 years. Limited data available in the first 6 months of life did not show failure of vision to develop. Grating acuity measurements overestimated eventual recognition acuity. Mean recognition acuity was 20/111. A relationship between grating acuity development and presence or absence of ocular pigment was not found. II. Grating acuity was significantly better for groups I and II under the condition of increased illumination (P < .03). For patients with albinism, grating acuity under standard illumination was significantly better than recognition acuity (P < .001). For all groups, grating acuity under increased illumination was significantly better than recognition acuity (P < .01). III. Mean recognition acuity in patients with albinism and melanin pigment in their maculas (20/47) was significantly better than measured recognition acuity in Project I (P < .001). All had foveal hypoplasia, but 8 patients had an incompletely developed annular reflex in the macula, 6 patients showed stereoacuity, and 3 patients had no nystagmus. CONCLUSIONS: I. Grating acuity development in albinism seems to progress along a curve that is asymptotic to visual development in a normal population. II. Increasing illumination does not reduce grating acuity in patients with albinism. Grating acuity overestimates recognition acuity in these patients. III. Ophthalmoscopic detection of melanin pigment in the macula in patients with albinism is associated with better vision.
PMCID: PMC1312119  PMID: 8981720
9.  Vision impairment in Liverpool: prevalence and morbidity. 
Archives of Disease in Childhood  1996;74(4):299-303.
A database related to the activities of the Liverpool vision assessment team was used to identify all children with vision impairment aged 0-16 years, resident in Liverpool, UK, on 1 April 1995. Prevalence rates were calculated for all children with vision impairment, and separately for two groups: those with uncomplicated vision impairment, and those with additional pathology. Visual tract pathologies were tabulated and compared. Associated handicapping conditions were defined and the extent of multiple disability was investigated for all vision impaired children, for very low birthweight children, and for those with cortical visual impairment. Of 199 children with vision impairment, 69 (35%) had uncomplicated impairment and 130 (65%) had additional and usually multiple pathology. There were 111 boys (56%); the excess of males was not statistically significant. Prevalence rates per 10,000 population were 18.1 for all vision impairment, 6.3 for uncomplicated vision impairment, and 11.8 for vision impairment complicated by additional pathology. Genetically determined disease accounted for over half the cases of uncomplicated vision impairment. Among the 130 children with additional pathology, cortical visual impairment was the commonest visual tract finding, affecting 64 (49%); 86% had learning difficulties; 53% had cerebral palsy. Multidisability (two or more disabling conditions in addition to vision impairment) affected half the entire childhood vision impairment population. These data should assist health and education authorities to determine the size of the vision impairment problem and how it relates to other disabilities in childhood, and can facilitate resource allocation and service planning.
PMCID: PMC1511464  PMID: 8669928
10.  Routine Eye Examinations for Persons 20-64 Years of Age 
Executive Summary
The objective of this analysis was to determine the strength of association between age, gender, ethnicity, family history of disease and refractive error and the risk of developing glaucoma or ARM?
Clinical Need
A routine eye exam serves a primary, secondary, and tertiary care role. In a primary care role, it allows contact with a doctor who can provide advice about eye care, which may reduce the incidence of eye disease and injury. In a secondary care role, it can via a case finding approach, diagnose persons with degenerative eye diseases such as glaucoma and or AMD, and lead to earlier treatment to slow the progression of the disease. Finally in a tertiary care role, it provides ongoing monitoring and treatment to those with diseases associated with vision loss.
Glaucoma is a progressive degenerative disease of the optic nerve, which causes gradual loss of peripheral (side) vision, and in advanced disease states loss of central vision. Blindness may results if glaucoma is not diagnosed and managed. The prevalence of primary open angle glaucoma (POAG) ranges from 1.1% to 3.0% in Western populations, and from 4.2% to 8.8% in populations of African descent. It is estimated up to 50% of people with glaucoma are aware that they have the disease. In Canada, glaucoma disease is the second leading cause of blindness in people aged 50 years and older. Tonometry, inspection of the optic disc and perimetry are used concurrently by physicians and optometrists to make the diagnosis of glaucoma. In general, the evidence shows that treating people with increased IOP only, increased IOP and clinical signs of early glaucoma or with normal-tension glaucoma can reduce the progression of disease.
Age-related maculopathy (ARM) is a degenerative disease of the macula, which is a part of the retina. Damage to the macula causes loss of central vision affecting the ability to read, recognize faces and to move about freely. ARM can be divided into an early- stage (early ARM) and a late-stage (AMD). AMD is the leading cause of blindness in developed countries. The prevalence of AMD increases with increasing age. It is estimated that 1% of people 55 years of age, 5% aged 75 to 84 years and 15% 80 years of age and older have AMD. ARM can be diagnosed during fundoscopy (ophthalmoscopy) which is a visual inspection of the retina by a physician or optometrist, or from a photograph of the retina. There is no cure or prevention for ARM. Likewise, there is currently no treatment to restore vision lost due to AMD. However, there are treatments to delay the progression of the disease and further loss of vision.
The Technology
A periodic oculo-visual assessment is defined “as an examination of the eye and vision system rendered primarily to determine if a patient has a simple refractive error (visual acuity assessment) including myopia, hypermetropia, presbyopia, anisometropia or astigmatism.” This service includes a history of the presenting complaint, past medical history, visual acuity examination, ocular mobility examination, slit lamp examination of the anterior segment, ophthalmoscopy, and tonometry (measurement of IOP) and is completed by either a physician or an optometrist.
Review Strategy
The Medical Advisory Secretariat conducted a computerized search of the literature in the following databases: OVID MEDLINE, MEDLINE, In-Process & Other Non-Indexed Citations, EMBASE, INAHTA and the Cochrane Library. The search was limited to English-language articles with human subjects, published from January 2000 to March 2006. In addition, a search was conducted for published guidelines, health technology assessments, and policy decisions. Bibliographies of references of relevant papers were searched for additional references that may have been missed in the computerized database search. Studies including participants 20 years and older, population-based prospective cohort studies, population-based cross-sectional studies when prospective cohort studies were unavailable or insufficient and studies determining and reporting the strength of association or risk- specific prevalence or incidence rates of either age, gender, ethnicity, refractive error or family history of disease and the risk of developing glaucoma or AMD were included in the review. The Grading of Recommendations Assessment, Development and Evaluation (GRADE) system was used to summarize the overall quality of the body of evidence.
Summary of Findings
A total of 498 citations for the period January 2000 through February 2006 were retrieved and an additional 313 were identified when the search was expanded to include articles published between 1990 and 1999. An additional 6 articles were obtained from bibliographies of relevant articles. Of these, 36 articles were retrieved for further evaluation. Upon review, 1 meta-analysis and 15 population-based epidemiological studies were accepted for this review
Primary Open Angle Glaucoma
Six cross-sectional studies and 1 prospective cohort study contributed data on the association between age and PAOG. From the data it can be concluded that the prevalence and 4-year incidence of POAG increases with increasing age. The odds of having POAG are statistically significantly greater for people 50 years of age and older relative to those 40 to 49 years of age. There is an estimated 7% per year incremental odds of having POAG in persons 40 years of age and older, and 10% per year in persons 49 years of age and older. POAG is undiagnosed in up to 50% of the population. The quality of the evidence is moderate.
Five cross-sectional studies evaluated the association between gender and POAG. Consistency in estimates is lacking among studies and because of this the association between gender and prevalent POAG is inconclusive. The quality of the evidence is very low.
Only 1 cross-sectional study compared the prevalence rates of POAG between black and white participants. These data suggest that prevalent glaucoma is statistically significantly greater in a black population 50 years of age and older compared with a white population of similar age. There is an overall 4-fold increase in prevalent POAG in a black population compared with a white population. This increase may be due to a confounding variable not accounted for in the analysis. The quality of the evidence is low.
Refractive Error
Four cross-sectional studies assessed the association of myopia and POAG. These data suggest an association between myopia defined as a spherical equivalent of -1.00D or worse and prevalent POAG. However, there is inconsistency in results regarding the statistical significance of the association between myopia when defined as a spherical equivalent of -0.5D. The quality of the evidence is very low.
Family History of POAG
Three cross-sectional studies investigated the association between family history of glaucoma and prevalent POAG. These data suggest a 2.5 to 3.0 fold increase in the odds having POAG in persons with a family history (any first-degree relative) of POAG. The quality of the evidence is moderate.
Age-Related Maculopathy
Four cohort studies evaluated the association between age and early ARM and AMD. After 55 years of age, the incidence of both early ARM and AMD increases with increasing age. Progression to AMD occurs in up to 12% of persons with early ARM. The quality of the evidence is low
Four cohort studies evaluated the association between gender and early ARM and AMD. Gender differences in incident early ARM and incident AMD are not supported from these data. The quality of the evidence is lows.
One meta-analysis and 2 cross-sectional studies reported the ethnic-specific prevalence rates of ARM. The data suggests that the prevalence of early ARM is higher in a white population compared with a black population. The data suggest that the ethnic-specific differences in the prevalence of AMD remain inconclusive.
Refractive Error
Two cohort studies investigated the association between refractive error and the development of incident early ARM and AMD. The quality of the evidence is very low.
Family History
Two cross-sectional studies evaluated the association of family history and early ARM and AMD. Data from one study supports an association between a positive family history of AMD and having AMD. The results of the study indicate an almost 4-fold increase in the odds of any AMD in a person with a family history of AMD. The quality of the evidence, as based on the GRADE criteria is moderate.
Economic Analysis
The prevalence of glaucoma is estimated at 1 to 3% for a Caucasian population and 4.2 to 8.8% for a black population. The incidence of glaucoma is estimated at 0.5 to 2.5% per year in the literature. The percentage of people who go blind per year as a result of glaucoma is approximately 0.55%.
The total population of Ontarians aged 50 to 64 years is estimated at 2.6 million based on the April 2006 Ontario Ministry of Finance population estimates. The range of utilization for a major eye examination in 2006/07 for this age group is estimated at 567,690 to 669,125, were coverage for major eye exams extended to this age group. This would represent a net increase in utilization of approximately 440,116 to 541,551.
The percentage of Ontario population categorized as black and/or those with a family history of glaucoma was approximately 20%. Therefore, the estimated range of utilization for a major eye examination in 2006/07 for this sub-population is estimated at 113,538 - 138,727 (20% of the estimated range of utilization in total population of 50-64 year olds in Ontario), were coverage for major eye exams extended to this sub-group. This would represent a net increase in utilization of approximately 88,023 to 108,310 within this sub-group.
The total cost of a major eye examination by a physician is $42.15, as per the 2006 Schedule of Benefits for Physician Services.(1) The total difference between the treatments of early-stage versus late-stage glaucoma was estimated at $167. The total cost per recipient was estimated at $891/person.
Current Ontario Policy
As of November 1, 2004 persons between 20 years and 64 years of age are eligible for an insured eye examination once every year if they have any of the following medical conditions: diabetes mellitus type 1 or 2, glaucoma, cataract(s), retinal disease, amblyopia, visual field defects, corneal disease, or strabismus. Persons between 20 to 64 years of age who do not have diabetes mellitus, glaucoma, cataract(s), retinal disease, amblyopia, visual field defects, corneal disease, or strabismus may be eligible for an annual eye examination if they have a valid “request for major eye examination” form completed by a physician (other than that who completed the eye exam) or a nurse practitioner working in a collaborative practice. Persons 20-64 years of age who are in receipt of social assistance and who do not have one of the 8 medical conditions listed above are eligible to receive an eye exam once every 2 years as a non-OHIP government funded service. Persons 19 years of age or younger and 65 years of age or older may receive an insured eye exam once every year.
Considerations for Policy Development
As of July 17, 2006 there were 1,402 practicing optometrists in Ontario. As of December 31, 2005 there were 404 practicing ophthalmologists in Ontario. It is unknown how many third party payers now cover routine eye exams for person between the ages of 20 and 64 years of age in Ontario.
PMCID: PMC3379534  PMID: 23074485
11.  Assessment and Management of Children with Visual Impairment 
The aim of this work was to evaluate the role of low vision aids in improving visual performance and response in children with low vision.
Study Design:
Prospective clinical case series.
Materials and Methods:
This study was conducted on 50 patients that met the international criteria for a diagnosis of low vision. Their ages ranged from 5 to 15 years. Assessment of low vision included distance and near visual acuity assessment, color vision and contrast sensitivity function. Low vision aids were prescribed based on initial evaluation and the patient's visual needs. Patients were followed up for 1 year using the tests done at the initial examination and a visual function assessment questionnaire.
The duration of visual impairment ranged from 1 to 10 years, with mean duration ± SD being 4.6± 2.3299. The near visual acuities ranged from A10 to A20, with mean near acuity ± SD being A13.632 ± 3.17171. Far visual acuities ranged from 6/60 (0.06) to 6/24 (0.25), with mean far visual acuity ± SD being 0.122 ± 0.1191. All patients had impaired contrast sensitivity function as tested using the vision contrast testing system (VCTS) chart for all spatial frequencies. Distance and near vision aids were prescribed according to the visual acuity and the visual needs of every patient. All patients in the age group 5-7 years could be integrated in mainstream schools. The remaining patients that were already integrated in schools demonstrated greater independency regarding reading books and copying from blackboards.
Our study confirmed that low vision aids could play an effective role in minimizing the impact of low vision and improving the visual performance of children with low vision, leading to maximizing their social and educational integration.
PMCID: PMC2813588  PMID: 20142963
Low Vision; Visual Aids; Contrast Sensitivity; Visual Acuity
12.  Ocular Morbidity among Refugees in Southwest Ethiopia 
Low vision and blindness are recognized as one of the major public health problems worldwide, especially in developing countries. The prevalence and cause of blindness and low vision vary from region to region, among different age and population groups in a country or geographical region. The objective of this study is thus to determine the causes of blindness and ocular morbidity among refugees in Southwest Ethiopia.
A cross-sectional clinic based study was conducted on 1,054 refugees in Southwest Ethiopia. A basic anterior and posterior segment examination was done by ophthalmologists with Magnifying Loupe 2.5X and Direct Ophthalmoscope. Data were analyzed using SPSS version 16.0.
The most common causes of ocular morbidity identified were trachoma 547(21.2%), cataract 501(19.4%), refractive error 353(13.7%), conjunctivitis 240(9.3%), glaucoma 130(5.1%) and climatic droplet keratopathy 112(4.4%). The overall prevalence of blindness was 26.2% and the prevalence of childhood blindness was 0.7%. The prevalence was higher among females (16.9%) than males (9.3%) and age groups 60 years and above (15.9%) than other age groups (10.3%) (P<0.05). The overall prevalence of low vision was 25.8% and the prevalence of low vision in pediatric age group was 0.9%. The leading causes of blindness were cataract 112(40.6%), trachomatous corneal opacity 58(21.0%) and glaucoma 49(17.8%). The commonest cause of low vision was cataract 102(37.6%) followed by trachomatous corneal opacity 49(18.1%) and refractive error 35(12.9%).
There is a very high burden of blinding eye diseases among refugees. Integrated multidisciplinary intervention strategies for the prevention and control of blindness and low vision in the study settings should be initiated.
PMCID: PMC4141226  PMID: 25183929
Blindness; low vision; ocular morbidity; refugees; Ethiopia
13.  Comparative Analysis of Circulating Endothelial Progenitor Cells in Age-Related Macular Degeneration Patients Using Automated Rare Cell Analysis (ARCA) and Fluorescence Activated Cell Sorting (FACS) 
PLoS ONE  2013;8(1):e55079.
Patients with age-related macular degeneration (ARMD) begin with non-neovascular (NNV) phenotypes usually associated with good vision. Approximately 20% of NNV-ARMD patients will convert to vision debilitating neovascular (NV) ARMD, but precise timing of this event is unknown. Developing a clinical test predicting impending conversion to NV-ARMD is necessary to prevent vision loss. Endothelial progenitor cells (EPCs), defined as CD34+VEGR2+ using traditional fluorescence activated cell sorting (FACS), are rare cell populations known to be elevated in patients with NV-ARMD compared to NNV-ARMD. FACS has high inter-observer variability and subjectivity when measuring rare cell populations precluding development into a diagnostic test. We hypothesized that automated rare cell analysis (ARCA), a validated and FDA-approved technology for reproducible rare cell identification, can enumerate EPCs in ARMD patients more reliably. This pilot study serves as the first step in developing methods for reproducibly predicting ARMD phenotype conversion.
We obtained peripheral venous blood samples in 23 subjects with NNV-ARMD or treatment naïve NV-ARMD. Strict criteria were used to exclude subjects with known angiogenic diseases to minimize confounding results. Blood samples were analyzed in masked fashion in two separate laboratories. EPCs were independently enumerated using ARCA and FACS within 24 hours of blood sample collection, and p<0.2 was considered indicative of a trend for this proof of concept study, while statistical significance was established at 0.05.
We measured levels of CD34+VEGFR2+ EPCs suggestive of a trend with higher values in patients with NV compared to NNV-ARMD (p = 0.17) using ARCA. Interestingly, CD34+VEGR2+ EPC analysis using FACS did not produce similar results (p = 0.94).
CD34+VEGR2+ may have predictive value for EPC enumeration in future ARCA studies. EPC measurements in a small sample size were suggestive of a trend in ARMD using ARCA but not FACS. ARCA could be a helpful tool for developing a predictive test for ARMD phenotype conversion.
PMCID: PMC3554681  PMID: 23359346
14.  Self-reported visual impairment and impact on vision-related activities in an elderly Nigerian population: report from the Ibadan Study of Ageing 
Ophthalmic epidemiology  2008;15(4):250-256.
Studies have shown an association between visual impairment and poor overall function. Studies from Africa and developing countries show high prevalence of visual impairment. More information is needed on the community prevalence and impact of visual impairment among elderly Africans.
A multi-stage stratified sampling of households was implemented to select persons aged 65 years and over in the south-western and north-central parts of Nigeria. Impairments of distant and near vision were based on subjective self-reports obtained with the use of items derived from the World Health Organization multi-country World Health Survey questionnaire. Impairment was defined as reporting much difficulty to questions on distant and near vision. Disabilities in activities of daily living (ADL) and instrumental activities of daily living (IADL) were evaluated by interview, using standardized scales.
A total of 2054 subjects 957 (46.6%) males and 1097 (53.4) females responded to the questions on vision. 22% (n=453) of the respondents reported distant vision impairment, and 18% (n=377) reported near vision impairment (not mutually exclusive). 15% (n= 312) however reported impairment for both far and near vision. Impairment of distant vision increased progressively with age (P < 0.01). Persons with self reported near vision impairment had elevated risk of functional disability in several IADLs and ADLs than those with out. Distant vision impairment was less associated with role limitations in both ADLs and IADLs.
The prevalence of self reported distant visual impairment was high but that for near visual impairment was less than expected in this elderly African population. Impairment of near vision was found to carry with it a higher burden of functional disability than that of distant vision.
PMCID: PMC2820717  PMID: 18780258
visual impairment; activities of daily living; functional disability
15.  Prevalence of blindness and low vision in Malaysian population: results from the National Eye Survey 1996 
Background: A national eye survey was conducted in 1996 to determine the prevalence of blindness and low vision and their major causes among the Malaysian population of all ages.
Methods: A stratified two stage cluster sampling design was used to randomly select primary and secondary sampling units. Interviews, visual acuity tests, and eye examinations on all individuals in the sampled households were performed. Estimates were weighted by factors adjusting for selection probability, non-response, and sampling coverage.
Results: The overall response rate was 69% (that is, living quarters response rate was 72.8% and household response rate was 95.1%). The age adjusted prevalence of bilateral blindness and low vision was 0.29% (95% CI 0.19 to 0.39%), and 2.44% (95% CI 2.18 to 2.69%) respectively. Females had a higher age adjusted prevalence of low vision compared to males. There was no significant difference in the prevalence of bilateral low vision and blindness among the four ethnic groups, and urban and rural residents. Cataract was the leading cause of blindness (39%) followed by retinal diseases (24%). Uncorrected refractive errors (48%) and cataract (36%) were the major causes of low vision.
Conclusion: Malaysia has blindness and visual impairment rates that are comparable with other countries in the South East Asia region. However, cataract and uncorrected refractive errors, though readily treatable, are still the leading causes of blindness, suggesting the need for an evaluation on accessibility and availability of eye care services and barriers to eye care utilisation in the country.
PMCID: PMC1771293  PMID: 12185113
prevalence; blindness; low vision; Malaysian
16.  Presenting Visual Acuities in a Referral Eye Center in an Oil-Producing Area of Nigeria 
To determine the pattern of presenting visual acuities at an eye center in the Niger Delta region of Nigeria.
Study Design:
Retrospective chart review
A retrospective review of patient records attending a private referral eye center providing services for company patients and the general public in the region. Information was obtained from computerized medical records of 6533 patients who attended the center for various eye concerns in a 5-year period (January 1998 to December 2002).
A total of 6533 patients were seen in this 5-year period of which 2472 (37.8%) were company patients and 4061 (62.2%). were private patients. There were 3879 males (59.4%) and 2654 females (40.6%). A visual acuity of 6/6 or better was seen in 50.8% of the patients. In 76.6% of patients, a visual acuity of 6/18 or better was recorded. There were 21.4% of patients in the low vision group. Bilateral blindness occurred in 2.1% of patients. Monocular blindness occurred in 3.7% of patients. Low vision occurred in 16.9% of company patients and 24.1% of private patients. Bilateral blindness occurred in 0.9% of company patients and 2.7% of private patients, while monocular blindness occurred in 1.2% of company patients and 5.2% of private patients. The main ocular problems were refractive error, glaucoma, conjunctivitis, headaches, ocular trauma, retina and related pathologies, cataract, uveitis, pterygium and corneal problems.
The incidence of low vision and blindness is high in the oil-producing area of the Niger Delta region of Nigeria. Low vision and blindness were more common in private patients than in company patients.
PMCID: PMC2813587  PMID: 20142966
Blindness; Niger delta; Nigeria; Visual acuity
17.  Impact of age related macular degeneration on quality of life 
To describe the impact of age related macular degeneration (AMD) on quality of life and explore the association with vision, health, and demographic variables.
Adult participants diagnosed with AMD and with impaired vision (visual acuity <6/12) were assessed with the Impact of Vision Impairment (IVI) questionnaire. Participants rated the extent that vision restricted participation in activities affecting quality of life and completed the Short Form General Health Survey (SF‐12) and a sociodemographic questionnaire.
The mean age of the 106 participants (66% female) was 83.6 years (range 64–98). One quarter had mild vision impairment, (VA<6/12–6/18) and 75% had moderate or severely impaired vision. Participants reported from at least “a little” concern on 23 of the 32 IVI items including reading, emotional health, mobility, and participation in relevant activities. Those with mild and moderate vision impairment were similarly affected but significantly different from those with severe vision loss (p<0.05). Distance vision was associated with IVI scores but not age, sex, or duration of vision loss.
AMD affects many quality of life related activities and not just those related to reading. Referral to low vision care services should be considered for people with mild vision loss and worse.
PMCID: PMC1857044  PMID: 16622089
age related macular degeneration; quality of life; vision impairment; low vision; rehabilitation
18.  The Artificial Silicon Retina in Retinitis Pigmentosa Patients (An American Ophthalmological Association Thesis) 
In a published pilot study, a light-activated microphotodiode-array chip, the artificial silicon retina (ASR), was implanted subretinally in 6 retinitis pigmentosa (RP) patients for up to 18 months. The ASR electrically induced retinal neurotrophic rescue of visual acuity, contrast, and color perception and raised several questions: (1) Would neurotrophic effects develop and persist in additionally implanted RP patients? (2) Could vision in these patients be reliably assessed? (3) Would the ASR be tolerated and function for extended periods?
Four additional RP patients were implanted and observed along with the 6 pilot patients. Of the 10 patients, 6 had vision levels that allowed for more standardized testing and were followed up for 7+ years utilizing ETDRS charts and a 4-alternative forced choice (AFC) Chow grating acuity test (CGAT). A 10-AFC Chow color test (CCT) extended the range of color vision testing. Histologic examination of the eyes of one patient, who died of an unrelated event, was performed.
The ASR was well tolerated, and improvement and/or slowing of vision loss occurred in all 6 patients. CGAT extended low vision acuity testing by logMAR 0.6. CCT expanded the range of color vision testing and correlated well with PV-16 (r = 0.77). An ASR recovered from a patient 5 years after implantation showed minor disruption and excellent electrical function.
ASR-implanted RP patients experienced prolonged neurotrophic rescue of vision. CGAT and CCT extended the range of acuity and color vision testing in low vision patients. ASR implantation may improve and prolong vision in RP patients.
PMCID: PMC3016083  PMID: 21212852
19.  Impact of self-reported visual impairment on quality of life in the Ibadan Study of Aging 
Information is lacking on the impact of visual impairment on the quality of life of elderly Africans. This study aims to examine the impact of self reported visual impairment on the quality life of an elderly Nigerian sample.
A multi-stage stratified sampling of households was implemented to select persons aged 65 years and over (n = 2054) in the south-western and north-central parts of Nigeria. Impairments of distant and near vision were based on subjective self-reports obtained with the use of items derived from the World Health Organization (WHO) multi-country World Health Survey questionnaire. Estimates of quality of life scores were made for normal sighted and visually impaired individuals using the WHO Quality of Life instrument, brief version (WHOQoL-Bref) .
Four hundred and fifty three (22.3%) of the respondents reported impairment for distant vision, 377 (18.4%) for near vision while 312 (15.2) reported impairment for both far and near. Impairment of near vision had a significant impact on all domains of quality of life. Distant vision had less impact, with significant decrement only in the domain of environment. After adjusting for the possible effects of age, sex, and co-occurring chronic physical illness, near vision impairment accounted for 3.92% decrement in the overall quality of life of elderly persons.
Impairment of vision is associated with significant decrement in diverse areas of quality of life in this elderly sample. Problems with near vision were nevertheless more likely than those of distant vision to affect quality of life.
PMCID: PMC2820710  PMID: 18296505
vision impairment; quality of life; elderly population
20.  Effectiveness of low vision services in improving patient quality of life at Aravind Eye Hospital 
Indian Journal of Ophthalmology  2014;62(12):1125-1131.
In India, where the heavy burden of visual impairment exists, low vision services are scarce and under-utilized.
Our study was designed to survey the effectiveness of low vision exams and visual aids in improving patient quality of life in southern rural India.
Subjects and Methods:
The low vision quality of life (LVQOL) questionnaire measures vision-related quality of life through 25 questions on a Likert scale of 0–5 that pertain to (1) mobility, distance vision, and lighting; (2) psychological adjustment; (3) reading and fine work; and (4) activities of daily living. This tool was translated into Tamil and verbally administered to 55 new low vision referral patients before their first visit at the low vision clinic at Aravind Eye Hospital. Low vision aids (LVAs) were prescribed at the discretion of the low vision specialist. 1-month later, the same questionnaire was administered over the phone.
About 44 of 55 low vision patients completed baseline and follow-up LVQOL surveys, and 30 normal vision controls matched for age, gender, and education were also surveyed (average 117.34 points). After the low vision clinic visit, the low vision group demonstrated a 4.55-point improvement in quality of life (from 77.77 to 82.33 points, P = 0.001). Adjusting for age, gender, and education, the low vision patients who also received LVAs (n = 24) experienced an even larger increase than those who did not (n = 20) (8.89 points, P < 0.001).
Low vision services and visual aids can improve the quality of life in South Indian rural population regardless of age, gender, and education level. Thus, all low vision patients who meet the criteria should be referred for evaluation.
PMCID: PMC4313491  PMID: 25579355
Low vision; low vision aids; quality of life
21.  Configuring Balanced Scorecards for Measuring Health System Performance: Evidence from 5 Years' Evaluation in Afghanistan 
PLoS Medicine  2011;8(7):e1001066.
Anbrasi Edward and colleagues report the results of a balanced scorecard performance system used to examine 29 key performance indicators over a 5-year period in Afghanistan, between 2004 and 2008.
In 2004, Afghanistan pioneered a balanced scorecard (BSC) performance system to manage the delivery of primary health care services. This study examines the trends of 29 key performance indicators over a 5-year period between 2004 and 2008.
Methods and Findings
Independent evaluations of performance in six domains were conducted annually through 5,500 patient observations and exit interviews and 1,500 provider interviews in >600 facilities selected by stratified random sampling in each province. Generalized estimating equation (GEE) models were used to assess trends in BSC parameters. There was a progressive improvement in the national median scores scaled from 0–100 between 2004 and 2008 in all six domains: patient and community satisfaction of services (65.3–84.5, p<0.0001); provider satisfaction (65.4–79.2, p<0.01); capacity for service provision (47.4–76.4, p<0.0001); quality of services (40.5–67.4, p<0.0001); and overall vision for pro-poor and pro-female health services (52.0–52.6). The financial domain also showed improvement until 2007 (84.4–95.7, p<0.01), after which user fees were eliminated. By 2008, all provinces achieved the upper benchmark of national median set in 2004.
The BSC has been successfully employed to assess and improve health service capacity and service delivery using performance benchmarking during the 5-year period. However, scorecard reconfigurations are needed to integrate effectiveness and efficiency measures and accommodate changes in health systems policy and strategy architecture to ensure its continued relevance and effectiveness as a comprehensive health system performance measure. The process of BSC design and implementation can serve as a valuable prototype for health policy planners managing performance in similar health care contexts.
Please see later in the article for the Editors' Summary
Editors' Summary
Traditionally, the performance of a health system (the complete network of health care agencies, facilities, and providers in a defined geographical region) has been measured in terms of health outcomes: how many people have been treated, how many got better, and how many died. But, nowadays, with increased demand for improved governance and accountability, policy makers are seeking comprehensive performance measures that show in detail how innovations designed to strengthen health systems are affecting service delivery and health outcomes. One such performance measure is the “balanced scorecard,” an integrated management and measurement tool that enables organizations to clarify their vision and strategy and translate them into action. The balanced scorecard—essentially a list of key performance indicators and performance benchmarks in several domains—was originally developed for industry but is now becoming a popular strategic management tool in the health sector. For example, balanced scorecards have been successfully integrated into the Dutch and Italian public health care systems.
Why Was This Study Done?
Little is known about the use of balanced scorecards in the national public health care systems of developing countries but the introduction of performance management into health system reform in fragile states in particular (developing countries where the state fails to perform the fundamental functions necessary to meet its citizens' basic needs and expectations) could help to promote governance and leadership, and facilitate essential policy changes. One fragile state that has introduced the balanced scorecard system for public health care management is Afghanistan, which emerged from decades of conflict in 2002 with some of the world's worst health indicators. To deal with an extremely high burden of disease, the Ministry of Public Health (MOPH) designed a Basic Package of Health Services (BPHS), which is delivered by nongovernmental organizations and MOPH agencies. In 2004, the MOPH introduced the National Health Service Performance Assessment (NHSPA), an annual country-wide assessment of service provision and patient satisfaction and pioneered a balanced scorecard, which uses data collected in the NHSPA, to manage the delivery of primary health care services. In this study, the researchers examine the trends between 2004 and 2008 of the 29 key performance indicators in six domains included in this balanced scorecard, and consider the potential and limitations of the scorecard as a management tool to measure and improve health service delivery in Afghanistan and other similar countries.
What Did the Researchers Do and Find?
Each year of the study, a random sample of 25 facilities (district hospitals and comprehensive and basic health centers) in 28 of Afghanistan's 34 provinces was chosen (one province did not have functional facilities in 2004 and the other five missing provinces were inaccessible because of ongoing conflicts). NHSPA surveyors collected approximately 5,000 patient observations, 5,000 exit interviews with patients or their caregivers, and 1,500 health provider interviews by observing consultations involving five children under 5 years old and five patients over 5 years old in each facility. The researchers then used this information to evaluate the key performance indicators in the balanced scorecard and a statistical method called generalized estimating equation modeling to assess trends in these indicators. They report that there was a progressive improvement in national average scores in all six domains (patients and community satisfaction with services, provider satisfaction, capacity for service provision, quality of services, overall vision for pro-poor and pro-female health services, and financial systems) between 2004 and 2008.
What Do These Findings Mean?
These findings suggest that the balanced scorecard was successfully used to improve health system capacity and service delivery through performance benchmarking over the 5-year study period. Importantly, the use of the balanced scorecard helped to show the effects of investments, facilitate policy change, and create a more evidence-based decision-making culture in Afghanistan's primary health care system. However, the researchers warn that the continuing success of the balanced scorecard in Afghanistan will depend on its ability to accommodate changes in health systems policy. Furthermore, reconfigurations of the scorecard are needed to include measures of the overall effectiveness and efficiency of the health system such as mortality rates. More generally, the researchers conclude that the balanced scorecard offers a promising measure of health system performance that could be used to examine the effectiveness of health care strategies and innovations in other fragile and developing countries.
Additional Information
Please access these Web sites via the online version of this summary at
A 2010 article entitled An Afghan Success Story: The Balanced Scorecard and Improved Health Services in The Globe, a newsletter produced by the Department of International Health at the John Hopkins Bloomberg School of Public Health, provides a detailed description of the balanced scorecard used in this study
Wikipedia has a page on health systems and on balanced scorecards (note that Wikipedia is a free online encyclopedia that anyone can edit; available in several languages)
The World Health Organization country profile of Afghanistan provides information on the country's health system and burden of disease (in several languages)
PMCID: PMC3144209  PMID: 21814499
22.  Phakic Intraocular Lenses for the Treatment of Refractive Errors 
Executive Summary
The objective of this analysis is to review the effectiveness, safety, and cost-effectiveness of phakic intraocular lenses (pIOLs) for the treatment of myopia, hyperopia, and astigmatism.
Clinical Need: Condition and Target Population
Refractive Errors
Refractive errors occur when the eye cannot focus light properly. In myopia (near- or short-sightedness), distant objects appear blurry because the axis of the eye is too long or the cornea is too steep, so light becomes focused in front of the retina. Hyperopia (far sightedness) occurs when light is focused behind the retina causing nearby objects to appear blurry. In astigmatism, blurred or distorted vision occurs when light is focused at two points rather than one due to an irregularly shaped cornea or lens.
Refractive errors are common worldwide, but high refractive errors are less common. In the United States, the prevalence of high myopia (≤ −5 D) in people aged 20 to 39, 40 to 59, and 60 years and older is 7.4% (95% confidence interval [CI], 6.5% – 8.3%), 7.8% (95% CI, 6.4% – 8.6%), and 3.1% (95% CI, 2.2% – 3.9%), respectively. The prevalence of high hyperopia (≥ 3 D) is 1.0% (95% CI, .6% – 1.4%), 2.4% (95% CI, 1.7% – 3.0%), and 10.0% (95% CI, 9.1% – 10.9%) for the same age groupings. Finally, the prevalence of astigmatism (≥ 1 D cylinder) is 23.1% (95% CI, 21.6% – 24.5%), 27.6% (95% CI, 25.8% – 29.3%) and 50.1% (48.2% – 52.0%).
Low Vision
According to the Ontario Schedule of Benefits, low visual acuity is defined by a best spectacle corrected visual acuity (BSCVA) of 20/50 (6/15) or less in the better eye and not amenable to further medical and/or surgical treatment. Similarly, the Ontario Assistive Devices Program defines low vision as BSCVA in the better eye in the range of 20/70 or less that cannot be corrected medically, surgically, or with ordinary eyeglasses or contact lenses.
Estimates of the prevalence of low vision vary. Using the criteria of BSCVA ranging from 20/70 to 20/160, one study estimated that 35.6 per 10,000 people in Canada have low vision. The 2001 Participation and Activity Limitation Survey (PALS) found that 594,350 (2.5%) Canadians had “difficulty seeing ordinary newsprint or clearly seeing the face of someone from 4 m,” and the Canadian National Institute for the Blind (CNIB) registry classified 105,000 (.35%) Canadians as visually disabled.
Phakic Intraocular Lenses (pIOL)
A phakic intraocular lens (pIOL) is a supplementary lens that is inserted into the anterior or posterior chamber of the eye to correct refractive errors (myopia, hyperopia, and astigmatism). Unlike in cataract surgery, the eye’s natural crystalline lens is not removed when the pIOL is inserted, so the eye retains its accommodative ability. In Canada and the United States, iris-fixated (anterior chamber lenses that are anchored to the iris with a claw) and posterior chamber lenses are the only types of pIOLs that are licensed by Health Canada and the Food and Drug Administration, respectively.
Evidence-Based Analysis Method
Research Questions & Methodology
What are the effectiveness, cost-effectiveness, and safety of pIOLs for the treatment of myopia, hyperopia, and astigmatism?
Do certain subgroups (e.g. high myopia and low vision) benefit more from pIOLs?
How do pIOLs compare with alternative surgical treatment options (LASIK, PRK, and CLE)?
Using appropriate keywords, a literature search was conducted up to January 2009. Systematic reviews, meta-analyses, randomized controlled trials, and observational studies with more than 20 eyes receiving pIOLs were eligible for inclusion. The primary outcomes of interest were uncorrected visual acuity (UCVA), predictability of manifest refraction spherical equivalent (MRSE), and adverse events. The GRADE approach was used to systematically and explicitly evaluate the quality of evidence.
Summary of Findings
The search identified 1,131 citations published between January 1, 2003, and January 16, 2009. Including a health technology assessment (HTA) identified in the bibliography review, 30 studies met the inclusion criteria: two HTAs; one systematic review; 20 pre-post observational studies; and seven comparative studies (five pIOL vs. LASIK, one pIOL vs. PRK, and one pIOL vs. CLE).
Both HTAs concluded that there was good evidence of the short-term efficacy and safety of pIOLs, however, their conclusions regarding long-term safety differed. The 2006 HTA found convincing evidence of long-term safety, while the 2009 HTA found no long-term evidence about the risks of complications including cataract development, corneal damage, and retinal detachment.
The systematic review of adverse events found that cataract development (incidence rate of 9.6% of eyes) is a substantial risk following posterior chamber pIOL implantation, while chronic endothelial cell loss is a safety concern after iris-fixated pIOL implantation. Adverse event rates varied by lens type, but they were more common in eyes that received posterior chamber pIOLs.
The evidence of pIOL effectiveness is based on pre-post case series. These studies reported a variety of outcomes and different follow-up time points. It was difficult to combine the data into meaningful summary measures as many time points are based on a single study with a very small sample size. Overall, the efficacy evidence is low to very low quality based on the GRADE Working Group Criteria.
For all refractive errors (low to high), most eyes experienced a substantial increase in uncorrected visual acuity (UCVA) with more than 75% of eyes achieving UCVA of 20/40 or better at all postoperative time points. The proportion of eyes that achieved postoperative UCVA 20/20 or better varied substantially according type of lens used and the type of refractive error being corrected, ranging from about 30% of eyes that received iris-fixated lenses for myopia to more than 78% of eyes that received posterior chamber toric lenses for myopic astigmatism.
Predictability of manifest refraction spherical equivalent (MRSE) within ± 2.0 D was very high (≥ 90%) for all types of lenses and refractive error. At most time points, more than 50% of eyes achieved a MRSE within ± 0.5 D of emmetropia and at least 85% within ± 1.0 D. Predictability was lower for eyes with more severe preoperative refractive errors. The mean postoperative MRSE was less than 1.0 D in all but two studies.
Safety, defined as a loss of two or more Snellen lines of best spectacle corrected visual acuity (BSCVA), was high for all refractive errors and lens types. Losses of two or more lines of BSCVA were uncommon, occurring in fewer than 2% of eyes that had received posterior chamber pIOLs for myopia, and less than 1% of eyes that received iris-fixated lens implantation for myopia. Most eyes did not experience a clinically significant change in BSCVA (i.e. loss of one line, no change, or gain of one line), but 10% to 20% of eyes gained two or more lines of BSCVA.
The pIOL outcomes for UCVA, predictability, BSCVA, and adverse events were compared with FDA targets and safety values for refractive surgery and found to meet or exceed these targets at most follow-up time points. The results were then stratified to examine the efficacy of pIOLs for high refractive errors. There was limited data for many outcomes and time points, but overall the results were similar to those for all levels of refractive error severity.
The studies that compared pIOLs with LASIK, PRK, and CLE for patients with moderate to high myopia and myopic astigmatism showed that pIOLs performed better than these alternative surgical options for the outcomes of:
predictability and stability of MRSE,
postoperative MRSE,
safety (measured as clinically significant loss of BSCVA), and
gains in BSCVA.
Correction of refractive cylinder (astigmatism) was the only outcome that favoured refractive surgery over pIOLs. This was observed for both toric and non-toric pIOLs (toric pIOLs correct for astigmatism, non-toric pIOLs do not).
Common adverse events in the LASIK groups were diffuse lamellar keratitis and striae in the corneal flap. In the pIOL groups, lens repositioning and lens opacities (both asymptomatic and visually significant cataracts) were the most commonly observed adverse events. These studies were determined to be of low to very low evidence quality based on the GRADE Working Group Criteria.
Eye, myopia, hyperopia, astigmatism, phakic intraocular lens, LASIK, PRK, uncorrected visual acuity, best corrected visual acuity, refractive errors, clear lens extraction
PMCID: PMC3377525  PMID: 23074518
The aim of this study was to determine the visual outcome of patients who had cataract surgery in the University College Hospital Ibadan.
This is an observational descriptive, longitudinal study of consecutive patients undergoing cataract surgery at the University College Hospital conducted between May and October 2007. A total of 184 patients who presented to the hospital and met the inclusion criteria were recruited into the study. Patients were examined preoperatively, 1st day postoperatively and 8th week postoperatively.
The mean age was 66.5 years; and the male to female ratio was 1.2:1. Preoperatively, 137 patients (74.5%) were blind in the operated eye, while 39 patients (23.6%) were blind in both eyes at presentation. At 1st day postoperatively, 87 patients (47.3%) had pinhole visual acuity of 6/6-6/18. Best corrected vision after refraction eight weeks postoperatively showed that 127 patients out of 161 patients (78.8%) had good vision while 28 patients (17.4%) had borderline vision, and six patients (3.8%) had severe visual impairment after refraction. The number of bilaterally blind patients also reduced from 39 (23.6%) to one (0.6%). Uncorrected refractive error was the commonest cause of poor vision prior to refraction. Glaucoma was the commonest ocular co-morbidity accounting for poor vision in 9.1% of patients eight weeks after cataract surgery.
This study demonstrates that good results can be obtained with cataract surgery and intraocular lens implantation in the developing world. More attention should be directed towards ensuring that successful outcomes are indeed being realized by continued monitoring of postoperative visual outcomes and prompt refraction for all patients.
PMCID: PMC4111036  PMID: 25161481
Cataract; Visual outcome; Cataract surgery.
24.  Cognitive Impairment and Age-Related Vision Disorders: Their Possible Relationship and the Evaluation of the Use of Aspirin and Statins in a 65 Years-and-Over Sardinian Population 
Neurological disorders (Alzheimer’s disease, vascular and mixed dementia) and visual loss (cataract, age-related macular degeneration, glaucoma, and diabetic retinopathy) are among the most common conditions that afflict people of at least 65 years of age. An increasing body of evidence is emerging, which demonstrates that memory and vision impairment are closely, significantly, and positively linked and that statins and aspirin may lessen the risk of developing age-related visual and neurological problems. However, clinical studies have produced contradictory results. Thus, the intent of the present study was to reliably establish whether a relationship exist between various types of dementia and age-related vision disorders, and to establish whether statins and aspirin may or may not have beneficial effects on these two types of disorders. We found that participants with dementia and/or vision problems were more likely to be depressed and displayed worse functional ability in basic and instrumental activities of daily living than controls. Mini mental state examination scores were significantly lower in patients with vision disorders compared to subjects without vision disorders. A closer association with macular degeneration was found in subjects with Alzheimer’s disease than in subjects without dementia or with vascular dementia, mixed dementia, or other types of age-related vision disorders. When we considered the associations between different types of dementia and vision disorders and the use of statins and aspirin, we found a significant positive association between Alzheimer’s disease and statins on their own or in combination with aspirin, indicating that these two drugs do not appear to reduce the risk of Alzheimer’s disease or improve its clinical evolution and may, on the contrary, favor its development. No significant association in statin use alone, aspirin use alone, or the combination of these was found in subjects without vision disorders but with dementia, and, similarly, none in subjects with vision disorders but without dementia. Overall, these results confirm the general impression so far; namely, that macular degeneration may contribute to cognitive disorders (Alzheimer’s disease in particular). In addition, they also suggest that, while statin and aspirin use may undoubtedly have some protective effects, they do not appear to be magic pills against the development of cognitive impairment or vision disorders in the elderly.
PMCID: PMC4224124  PMID: 25426067
age-related vision disorders; dementia; statins; aspirin; elderly
25.  N-Acetylcarnosine sustained drug delivery eye drops to control the signs of ageless vision: Glare sensitivity, cataract amelioration and quality of vision currently available treatment for the challenging 50,000-patient population 
Innovative Vision Products, Inc. (IVP)’s scientists developed the lubricant eye drops (Can-C™) designed as 1% N-acetylcarnosine (NAC) prodrug of l-carnosine containing a mucoadhesive cellulose-based compound combined with corneal absorption promoters in a sustained drug delivery system. Only the natural l-isomeric form of NAC raw material was specifically synthesized at the cGMP facility and employed for the manufacturing of Can-C™ eye drops.
Objective and study design:
In the present clinical study the authors assessed vision before and after 9 month term of topical ocular administration of NAC lubricant eye drops or placebo in 75 symptomatic patients with age-related uncomplicated cataracts in one or both eyes, with acuity in one eye of 20/40 or worse (best-corrected distance), and no previous cataract surgery in either eye and no other ocular abnormality and 72 noncataract subjects ranged in age from 54 to 78 years.
Subjects in these subsample groups have reported complaints of glare and wanted to administer eye drops to get quick eye relief and quality of vision for their daily activities including driving and computer works. Following 9 months of treatment with NAC lubricant eye drops, most patients’ glare scores were improved or returned to normal in disability glare tests with Halometer DG. Improvement in disability glare was accompanied with independent improvement in acuity. Furthermore, patients with the poorest pretreatment vision were as likely to regain certain better visual function after 9 months of treatment with N-acetylcarnosine lubricant eye drops as those with the worth pretreatment vision.
Patients or other participants:
The authors made a reference to electronic records of the product sales to patients who have been made the repurchase of the Can-C™ eye drops since December 2001.
Based on this analysis of recorded adjustments to inventory, various parameters were analyzed during the continued repurchase behavior program, including testimonials from buyers. With these figures, researchers judged on the patients’ compliance rate to self-administer NAC eye-drops.
Main outcome measure and results:
The ophthalmic drug showed potential for the non-surgical treatment of age-related cataracts for participants after controlling for age, gender and daily activities and on a combined basis of repurchases behavior reports in more than 50,000 various cohort survivors, has been demonstrated to have a high efficacy and good tolerability for prevention and treatment of visual impairment determined for the older population with relative stable pattern of causes for blindness and visual impairment. The mechanisms of prevention and reversal of cataracts with NAC ophthalmic drug are considered which include prevention by the intraocular released carnosine of free-radical-induced inactivation of proprietary lens antioxidant enzymes (superoxide dismutase); prevention of carbohydrate and metal-catalyzed autooxidation of ascorbic acid-induced cross-linking glycation reactions to the lens proteins; transglycation properties of carnosine, allowing it to compete for the glycating agent, protecting proteins (lens crystallins) against modification; universal antioxidant and scavenging activity towards lipid hydroperoxides, aldehydes and oxygen radicals; activation with l-carnosine ingredient of proteasome activity in the lens; chaperone-like disaggregating to lens crystallins activity of NAC and of its bioactivated principal carnosine. Blindness incidence increased with advancing age, such as cataract and glaucoma, which are by far the commonest causes of blindness in our sample and in all age groups, glaucomatous neurodegeneration can be treated with developed NAC autoinduction prodrug eye drops equipped with corneal absorption promoters. The common blinding affections presenting in developed countries such as, senile macular degeneration, hereditary chorioretinal dystrophies, diabetic retinopathy are poorly represented in our current summary of vital-statistics and will be reported inherent in next N-acetylcarnosine ophthalmic drug studies.
The authors present evidence, about why only a certain kind of NAC is safe, and why only certain formulas designed by IVP for drug discovery are efficacious in the prevention and treatment of senile cataract for long-term use. Overall cumulated studies demonstrate that the designed by IVP new vision-saving drug NAC eye drops help the aging eye to recover by improving its clarity, glare sensitivity, color perception and overall vision.
PMCID: PMC2685223  PMID: 19503764
age-related ophthalmic diseases; cataract; disability-glare; halos; Halometer; visual-acuity; N-acetylcarnosine lubricant eye drops; repurchase behavior analysis; 50,000-patients’ compliance to self-administer eye drops

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