ArticlePDF Available

Profile of low vision clinics in eastern region of Nepal: A retrospective study

Authors:

Abstract and Figures

The entire low vision patients’ file that underwent low vision examination in 2009 in two major eye hospitals was retrospectively reviewed. Out of 1547 cases, 1140 (73.69%) were male and 407 (26.31%) were female. The mean age of presentation was 31.04 ± 20.63 years, of which 89.1 percent were from a rural community, 39.10 percent had avoidable blindness. Refractive error and amblyopia (24%) and retinitis pigmentosa (22.4%) were the most common causes of low vision. Refractive error and amblyopia (30.33%), retinitis pigmentosa (29.03%) and age related macular degeneration (ARMD) (36.5%) were the major causes of low vision in 0—15, >15—60 and >60 years age group respectively. The number of patients 1107 (71.55%) improved significantly with refractive correction. Eighty-eight (5.68%) were prescribed telescopes. For near vision, only 359 (23.2%) patients were prescribed magnifiers. There was a significant improvement of functional vision after provision of low vision devices, particularly for patients with residual vision better than 20/1200.
Content may be subject to copyright.
http://jvi.sagepub.com/
British Journal of Visual Impairment
http://jvi.sagepub.com/content/29/3/215
The online version of this article can be found at:
DOI: 10.1177/0264619611414990
2011 29: 215British Journal of Visual Impairment
Ajit Kumar Thakur, Purushottam Joshi, Himal Kandel and Subhash Bhatta
Profile of low vision clinics in eastern region of Nepal : A retrospective study
Published by:
http://www.sagepublications.com
can be found at:British Journal of Visual ImpairmentAdditional services and information for
http://jvi.sagepub.com/cgi/alertsEmail Alerts:
http://jvi.sagepub.com/subscriptionsSubscriptions:
http://www.sagepub.com/journalsReprints.navReprints:
http://www.sagepub.com/journalsPermissions.navPermissions:
http://jvi.sagepub.com/content/29/3/215.refs.htmlCitations:
at HINARI on September 2, 2011jvi.sagepub.comDownloaded from
215
THE BRITISH
JOURNAL OF
VISUAL
IMPAIRMENT
Copyright © 2011 Authors
(Los Angeles, London, New Delhi,
Singapore and Washington DC)
Vol 29(3): 215–226
DOI: 10.1177/0264619611414990
RESEARCH REPORT
BJVI
Profile of low vision clinics in
eastern region of Nepal
A retrospective study
AJIT KUMAR THAKUR Mechi Eye Hospital, Anarmani-7, Jhapa, Nepal
PURUSHOTTAM JOSHI Mechi Eye Hospital, Anarmani-7, Jhapa, Nepal
HIMAL KANDEL Institute of Medicine, Maharajgunj, Kathmandu Nepal
SUBHASH BHATTA Institute of Medicine, Maharajgunj, Kathmandu, Nepal
ABSTRACT The entire low vision patients’ file that underwent
low vision examination in 2009 in two major eye hospitals was
retrospectively reviewed. Out of 1547 cases, 1140 (73.69%)
were male and 407 (26.31%) were female. The mean age of
presentation was 31.04 ± 20.63 years, of which 89.1 percent
were from a rural community, 39.10 percent had avoidable
blindness. Refractive error and amblyopia (24%) and retinitis
pigmentosa (22.4%) were the most common causes of low
vision. Refractive error and amblyopia (30.33%), retinitis
pigmentosa (29.03%) and age related macular degeneration
(ARMD) (36.5%) were the major causes of low vision in 0–15,
>15–60 and >60 years age group respectively. The number of
patients 1107 (71.55%) improved significantly with refractive
correction. Eighty-eight (5.68%) were prescribed telescopes. For
near vision, only 359 (23.2%) patients were prescribed magnifiers.
There was a significant improvement of functional vision after
provision of low vision devices, particularly for patients with
residual vision better than 20/1200.
KEY WORDS avoidable blindness, causes of low
vision, refractive error, retinitis pigmentosa,
age related macular degeneration (ARMD)
A person with low vision is someone who has an impairment of visual
functioning despite treatment and/or standard refractive correction. The
World Health Organization (WHO) has classified the visual status of a
person in four categories (WHO, 2009):
at HINARI on September 2, 2011jvi.sagepub.comDownloaded from
THE BRITISH JOURNAL OF VISUAL IMPAIRMENT 29(3)
216
• apersonhavingbestcorrectedvision,inbetter eye,better than or
equal to 6/18 is said to have normal visual status;
• apersonwithbestcorrected vision, in better eye,<6/18to6/60is
said to have visual impairment;
• apersonhavingbestcorrectedvision,inbettereye,<6/60to3/60is
said to have severe visual impairment;
• apersonhavingvisualacuity<3/60issaidtobeblind.
Visually impaired people are those who have visual acuity of less than
6/18 to light perception and/or a visual field of less than 10° from the
point of fixation and who are using or are potentially able to use their
vision for planning and/or execution of a task (WHO, 1993). Globally,
about 314 million people are visually impaired and 45 million of them
are blind. However, correctable refractive error as a cause of visual
impairment is not included in that number, which implies that the actual
global magnitude of visual impairment is greater (Siddiqui, Bäckman and
Awan, 1997). Further, 75 percent of this visual impairment is estimated to
be avoidable (preventable or curable) (WHO, 2004). In 1999, the WHO
Prevention of Blindness Program launched ‘VISION 2020: The Right to
Sight Initiative’ with the objective of assisting member states in eliminating
avoidable blindness by the year 2020 (Thylefors, 1998). The global target
is to ultimately reduce blindness prevalence to less than 0.5 percent in all
countries, or less than 1.0 percent in any community (WHO, 2005).
Nearly 87 percent of the world’s blind people live in the developing
countries (Siddiqui et al., 1997). More than half of them live in Asia and
a vast majority of them are in rural communities (Nepal Facts and
Figures, 2010). Many reasons have been identified for the rising tide of
blindness and low vision. Prominent among them is the increase of the
world’s elderly population, particularly in developing countries.
Nepal is one of the poorest countries of Asia situated between India and
China. The prevalence of blindness is 0.84 per 100 inhabitants. Cataract
(66.8%) and its sequelae (5.3%) are the major causes of blindness.
Other causes are retinal disease (3.2%), glaucoma (3.2%), and trachoma
(3.2%). Of the total blind population, 92 percent live in rural areas
(Brilliant et al., 1988). The higher percentage of avoidable blindness
reflects the poor health access of the community due to poor health
education and poor financial conditions due to the political instability
(Nepal Facts and Figures, 2010). The prevalence of low vision is 1.0
percent as estimated by Nepal Netra Jyoti Sangh (NNJS), a leading NGO
in eye care in Nepal (NNJS, 2002). NNJS launched the National Low
Vision Program in Nepal in 2005 with the aim of helping people who
at HINARI on September 2, 2011jvi.sagepub.comDownloaded from
THAKUR ET AL.: LOW VISION CLINICS IN EASTERN NEPAL
217
have incurable eye conditions with some residual vision to make best
use of their vision. It also aims to bring them into the mainstream of
society by helping them to use the residual vision to the best possible
extent with the use of low vision devices. This program has given
priority to pick the low vision patients from the community. The focus
groups who were trained for low vision screening were school teachers,
Community based rehabilitation, and eye care personnel.
No nationwide study has been conducted in low vision to date. A report
from Lumbini, in the western part of the country, showed lens related
conditions (e.g. cataract and its sequel) as the main causes of low vision
(35.55%) followed by refractive errors/amblyopia (19.23%), retinitis
pigmentosa (7.24%) and other retinal causes (6.64%) (KC et al., 2007).
In a report from Kathmandu, the capital, situated in the central region
of the country, the major cause of low vision was diabetic retinopathy
(15.8%), followed by macular diseases (13.2%), age related macular
degeneration (10.5%), retinitis pigmentosa (9.6%) and amblyopia
(8.8%) (Paudel, Khadka and Sharma, 2005). Hence the distribution of
the causes for low vision in this country appears to vary significantly
from place to place. No data on low vision services has been published
from the eastern part of the country.
This study was aimed to determine the most common causes of low
vision in different age groups which would help in the national low
vision planning. This study also aimed at determining the improvement
of visual acuity after the provision of low vision services. This
information would give an idea about the status of the low vision
services in eastern Nepal. Hence, it would help in the planning of
newer programs to address the lacuna in the model of the current
service. It will also provide a guideline to develop low vision services
in other developing countries as well.
METHODOLOGY
A retrospective study was carried out in two major eye hospitals of
eastern Nepal: Sagarmatha Choudhary Eye Hospital, Lahan and Mechi
Eye Hospital, Jhapa. The medical records of all the cases who visited
these hospitals in the year 2008 and 2009 were reviewed. The data
included by whom they were referred, consisted of age, sex, profession,
education level, their chief visual demands and difficulties, presenting
distance and near visual acuity, visual acuity with refractive correction,
types of refractive error, visual acuity with low vision devices and their
preferences, and the most commonly prescribed low vision devices.
at HINARI on September 2, 2011jvi.sagepub.comDownloaded from
THE BRITISH JOURNAL OF VISUAL IMPAIRMENT 29(3)
218
Distance visual acuity was recorded in logMAR unit and was converted
into Snellen fraction. Similarly near visual acuity was tested at their
working distance with preferred light conditions for reading and was
recorded in M notation. Objective and subjective refraction was carried
out in all cases. Proper refractive correction was prescribed in spectacle
form. A trial of telescopes was carried out for suitable patients, and the
visual acuity with telescopes was noted. Similarly, the near magnifiers
of appropriate magnification were tried, and the near visual acuity with
magnifiers was noted. Preference of magnifiers was also documented.
Data was recorded and analysed using SPSS 14 software.
RESULTS
Demographic distribution
The total number of low vision cases included in the study period was
1547, of which 1361 (87.98%) of cases were referred from the eye care
professionals, 134 (8.66%) were referred from school teachers, 42
(2.71%) were referred from Community based rehabilitation and 10
(0.65%) from eye camps and other medical personnel.
Out of 1547, 1140 (73.69%) were male and 407 (26.31%) were female.
The mean age of presentation was 31.04 ± 20.63 years ranging from
3–87 years. There were 501 (32.38%) patients in the 0–15 years age
group, 868 (56.10%) of patients were in the group >15–60 years
age group and 178 (11.52%) patients were in the group >60 years age
group. There were 1379 (89.1%) patients from rural communities and
only 168 (10.9%) patients were from urban society.
Causes of low vision
Out of 1547 cases presented to the low vision clinics, 605 (39.10%)
had avoidable causes for visual impairment. Out of 605, 485 (80.1%)
were preventable and 120 (19.90%) were curable.
The causes of low vision in patients attending the low vision clinics are
shown in Figure 1. Refractive error and amblyopia (24%) and retinitis
pigmentosa (22.4%) were most common causes of low vision. Other
causes were globe anomalies (9.57%), optic atrophy (8.9%), congenital
cataract (8.7%), heredo macular degeneration (7.69%), age related
macular degeneration (5.7%), corneal opacity (5.1%), nystagmus associated
with unknown causes (4.1%), glaucoma (2.2%), albinism (1.1%) and
others (1.2%).
at HINARI on September 2, 2011jvi.sagepub.comDownloaded from
THAKUR ET AL.: LOW VISION CLINICS IN EASTERN NEPAL
219
24% 22.40%
9.57% 8.90% 7.75% 7.69%
5.70% 5.10% 4% 2.20% 1.20% 1.09%
0%
5%
10%
15%
20%
25%
30%
Figure 1. Causes of low vision in patients attending low vision clinics.
Table 1. Table showing causes of low vision in different age groups.
Causes of
Low Vision
0–15 years
(n = 501)
>15–60
years
(n = 868)
>60 years
(n = 178) Total
Congenital
Cataract
59 (11.8%) 56 (6.45%) 5 (2.80) 120 (7.75%)
Albinism 10 (2%) 7 (0.8%) 0 (0%) 17 (1.09%)
Globe anomaly 76 (15.1%) 69 (7.94%) 3 (5.93%) 148 (9.56%)
Corneal opacity 40 (7.98%) 31 (3.57%) 8 (4.49%) 79 (5.1%)
Glaucomatous
optic atrophy
3 (0.59%) 24 (2.76%) 8 (4.49%) 35 (2.26)
Refractive
error and
Amblyopia
152(30.33%) 205 (23.61%) 14 (7.86%) 371 (23.98%)
Macular
disease
(except AMD)
14 (2.79%) 88 (10.13%) 17 (9.55%) 119 (7.69%)
Nystagmus
associated
with unknown
causes
36 (7.18%) 26 (2.99%) 1 (0.06%) 63 (4.07%)
Optic atrophy 38 (7.58%) 76 (8.75%) 24 (13.48%) 138 (8.92%)
Retinitis
pigmentosa
70 (13.97%) 252 (29.03%) 25 (14.04%) 347 (22.43%)
ARMD 0 (0%) 23 (2.64%) 65 (36.51%) 88 (5.68%)
Others 3 (0.59%) 11 (1.26%) 8 (4.49%) 22 (1.42%)
at HINARI on September 2, 2011jvi.sagepub.comDownloaded from
THE BRITISH JOURNAL OF VISUAL IMPAIRMENT 29(3)
220
In the 0–15 year age group, the most common causes of low vision
were refractive error and amblyopia (30.33%), retinitis pigmentosa
(13.97%) and globe anomalies (15.1%) and congenital cataract
(11.8%). Similarly, retinitis pigmentosa (29.03%), refractive error and
amblyopia (23.61%) and heredo macular degenerations (10.13%)
were the most common causes of low vision in >15–60 years. Age
related macular degeneration (36.5%), retinitis pigmentosa (14.04%)
and optic atrophy (13.48%) were the most common causes in the age
group >60 years.
Visual status
Out of 1547 low vision patients, 819 (52.9%) were bilaterally blind and
only 725 (47.1%) had residual vision better than 3/60 in the better eye.
Out of 725, 418 (57.66%) were visually impaired and 307 (32.34%)
were with severe visual impairment according to WHO classification of
visual status (WHO, 2009).
Low vision services
The chief visual complaints for distance were recognizing faces
(n=1195) and reading the chalk board letter (n=435). For near, the
chief visual demands were reading print (n=678) and coin identification
(n=171). Other visual problems included mobility problem (n= 314),
glare problem (n=208) and problem in night vision (n=389).
Mean visual acuity was 0.08 (6/72) in Snellen notation that ranged from
(0.004–0.33) 6/1500 to 6/18. The mean visual acuity with refractive
correction was 0.14 (6/42). The improvement of visual acuity from
baseline with refractive correction was statistically significant (p<0.05,
paired ttest). The visual acuity with telescopes (n=303) was 0.43 (6/14).
When the patients whose residual vision was better than 0.05 (3/60)
were only taken into account, the mean presenting visual acuity was
0.13 (6/45) which improved to 6/30 with refractive correction. Mean
visual acuity with telescopes in this group (n=159) was 0.48 (6/12.5).
The improvement of visual acuity with both refractive correction and
telescopes were statistically significant p<0.05,pairedttest)
The mean presenting near visual acuity was 2.12 ± 1.49 M units which
improved to 1.63±1.2 M units with different magnifiers. Similarly when
only the patients whose residual vision was better than 0.05 (3/60) in
the better eye were taken into account, the mean near visual acuity was
at HINARI on September 2, 2011jvi.sagepub.comDownloaded from
THAKUR ET AL.: LOW VISION CLINICS IN EASTERN NEPAL
221
1.77±1.22 M unit which improved to 1.29±0.77 M units with low
vision devices. The improvement of near visual acuity with magnifiers
was statistically significant (p<0.05,pairedttest) and improvement was
even more when the low vision persons had residual vision better than
0.05 (3/60).
There were 1107 (71.55%) patients who improved significantly with
refractive correction alone and were prescribed glasses. Eighty-eight
(5.68%) were prescribed telescopes. For near, only 359 (23.2%) patients
were prescribed magnifiers. Spectacle magnifiers was the most frequently
prescribed device for near.
DISCUSSION
Community based rehabilitation (CBR) is a home and community based
program for the blind people of the community, successfully running in
14 districts of Nepal. The main function of CBR is to identify the
incurably blind people and initiate suitable programs, such as early
intervention, education, orientation, mobility and vocational trainings.
Teachers in the developing country are best suited to provide health
education to the community. In our study, only 134 (8.66%) subjects
were referred by school teachers, 42 (2.71%) were referred by
Community based rehabilitation to the low vision clinics. This highlights
the need of active participation of teachers and rehabilitation workers
in this sector. The CBR program is successfully running in the Jhapa
District where Mechi Eye Hospital is situated but not in Siraha, where
Sagarmatha Choudhary Eye Hospital, Lahan is situated and this might
be the cause for the fewer number of patient referrals from CBR seen in
this study. The remaining patients were referred from the eye care
professionals that included ophthalmologists, optometrists and
ophthalmic assistants. Nepal is a country where the majority of people
Table 2. Table showing the prescribed devices for near.
Magnifiers Number of patients Percentage
Spectacle magnifier 246 68.52%
Hand Held Magnifier 29 8.07%
Stand magnifier 76 21.16%
Bar magnifier 7 1.94%
Tele-microscopes 1 0.27%
CCTV 4 1.11%
at HINARI on September 2, 2011jvi.sagepub.comDownloaded from
THE BRITISH JOURNAL OF VISUAL IMPAIRMENT 29(3)
222
live in rural communities and they have traditional beliefs in faith
healers. There may be advantages in training these faith healers to
identify the cases of possible visual impairment and encourage them to
visit the low vision clinics.
In this study, male to female ratio was 2.80. The male preponderance
was also seen in the study done by Mohidin and Yusoff (1998) where
the ratio was 2.21. It indicates that low vision was more prevalent in
males in Nepal, although it might also be linked to males having more
access to hospital care. In Nepal, gender-based discrimination is
widespread and extends to ownership of productive assets (such as
cattle), access to resources like land and other properties, access to
health and educational opportunities, work burden, access to public
decision-making positions, mobility, and overall cultural status. As a
result the structured dependence of women on men is high. Despite
progressive policy reforms, human development indicators of Nepali
women and girls, especially from marginalized castes and ethnicities,
living in remote areas, remain low (UNFPA Nepal, 2011). This suggests
that Nepal may benefit from a low vision screening camp in the
community which could give health education along with screening
services which particularly emphasizes the needs of female patients.
The mean age of presentation was 31.04± 20.63 years ranging from
3–87 years. There were 501 (32.38%) patients in 0–15 year age group,
868 (56.10%) of patients were in >15–60 years age group and 178
(11.52%) in the >60 years age group. The majority of the patients were
from younger age groups which was similar to the result shown by
Mohidin and Yusoff (1998). In their study, 73.8 percent of patients were
younger than 60 years. The fewer number of patients in the age group
>60 years might be due to lower life expectancy (65.81 years) of the
country (Nepal life expectancy at birth, 2010). In our study, 1379
(89.1%) patients were from rural areas and only 168 (10.9%) patients
were from urban areas. In Nepal, more than 80 percent of the population
live in villages and the hospitals where the study was conducted are in
close proximity to villages.
Refractive error and amblyopia (24%) and retinitis pigmentosa (22.4%)
were the most common causes of low vision in the study population.
Other causes included globe anomalies (9.57%), optic atrophy (8.9%),
congenital cataract (8.7%), heredo macular degeneration (7.69%), age
related macular degeneration (5.7%), nystagmus due to unknown
causes (4.1%), glaucoma (2.2%), albinism (1.1%) and others (1.2%).
at HINARI on September 2, 2011jvi.sagepub.comDownloaded from
THAKUR ET AL.: LOW VISION CLINICS IN EASTERN NEPAL
223
Mohidin and Yusoff found structural and functional defect of globe
(13%), retinitis pigmentosa (13%) and heredo macular dystrophy (10%)
as causes of low vision in their study (Mohidin and Yusoff, 1998). An
exceptionally high percentage of refractive error and amblyopia reflects
the burden of refractive error in this part of the world. It might be due
to nuclear sclerosis which was not operated upon due to lack of
facilities and had visual acuity better than 6/36 with spectacles. In this
region, surgery is usually indicated only when the improvement with
spectacles was not better than 6/60.
Causes of low vision were analysed separately in different age groups.
The most common causes of low vision were refractive error and
amblyopia (30.33%), retinitis pigmentosa (13.97%) and globe anomalies
(15.1%) and congenital cataract (11.8%) in the 0–15 years age group.
In a study done by Elfadul Mohamed and Binnawi, retinitis pigmentosa
was the commonest (16.7 %) followed by congenital cataract (14.2 %)
(Elfadul Mohamed and Binnawi, 2009). In a study by Bamashmus and
Al-Akily, the commonest causes of bilateral blindness were cataract
(20.0%), glaucoma (17.8%), retinal disorders (13.3%) and corneal non-
traumatic opacities (13.3%) (Bamashmus and Al-Akily, 2010). Again the
high percentage of refractive error and amblyopia as a cause of low
vision seeks attention of the eye care planners to initiate much more
pre-school and school screening programs to reduce the visual
impairment in the paediatric age group.
Similarly, retinitis pigmentosa (29.03%), refractive error (23.61%) and
heredo macular degenerations (10.13%) were the most common causes
of low vision in >15–60 years age group. Age related macular
degeneration (36.5%), retinitis pigmentosa (14.04%) and optic atrophy
(13.48%) were the most common causes of low vision in the age group
>60 years. Similar results were shown by Mohidin and Yusoff (1998).
The fewer number of age related macular degeneration patients in the
study population was probably due to relatively fewer number of
patients in the elderly age group.
Out of 1547 low vision patients, 819 (52.9%) were bilaterally blind and
only 725 (47.1%) had residual vision better then 3/60 in the better eye
in contrast to the study by Elfadul Mohamed and Binnawi (2009) where
a higher number of bilateral blind persons reflects the poor health
awareness and accessibility to health services in this part of the country.
A large number of patients (39.10%) had avoidable causes for visual
impairment. This reflects the lack of awareness and inaccessibility of
at HINARI on September 2, 2011jvi.sagepub.comDownloaded from
THE BRITISH JOURNAL OF VISUAL IMPAIRMENT 29(3)
224
primary eye care to the patients in this area. This may benefit from both
governmental and nongovernmental organization attention.
The improvement of visual acuity for near and distance was significant
after provision of low vision devices. Even refractive correction alone
had resulted in significant improvement in visual acuity while telescopes
improved visual acuity to make their visual status near to normal. The
improvement of visual acuity was more when only the patients were
taken into account whose vision was better than 3/60 at presentation.
Hence the low vision service has better impact when the patient has
better residual vision. This result emphasizes the strengthening of the
primary eye care program so that cases of low vision can be detected
at an earlier stage where the impact of the service is greater. There were
1107 (71.55%) patients who improved significantly with refractive
correction alone and were prescribed spectacles. Telescopes were
prescribed to 88 (5.68%) patients.
Mohidin and Yusoff have shown that 60 percent of low vision clients
were prescribed at least one low vision device (Mohidin and Yusoff,
1998). For near, only 359 (23.2%) patients were prescribed magnifiers.
More than 90 percent of the optical devices like spectacles, hand held
magnifiers, spectacle magnifiers, were simple to use and are easily
available in the eye hospitals.
CONCLUSION
The low vision service through the low vision clinics in the eastern
region of Nepal is satisfactory in terms of the number of patients
attending the clinics. A good number of patients visit low vision clinics.
But the patients presented to the clinics usually are bilaterally blind. So
there needs to be a screening program for low vision patients in the
community which can identify patients earlier. The services provided at
the low vision clinics in this part of the country are satisfactory, as after
the provision of the devices, the visual functions have improved
significantly. The majority of devices are available in the local low vision
clinics at the hospital. The National Low Vision Program is supporting
the patients by providing the low vision devices at a 10 percent subsidy.
Only providing low vision services to the people with low vision does
not solve the problem. There should be a proper monitoring on the use
of devices and the impact they have upon patients after the provision of
low vision services. Nevertheless, such follow-up work is expensive and
currently limited. Close work with school teachers and community
at HINARI on September 2, 2011jvi.sagepub.comDownloaded from
THAKUR ET AL.: LOW VISION CLINICS IN EASTERN NEPAL
225
blind rehabilitators may offer more affordable ways of undertaking this
evaluation. Greater communication between low vision services and
other community-based services therefore seems a priority.
The higher incidence of avoidable blindness draws attention to the
need to strengthen primary eye care and emphasize early detection
and the necessary action. Uncorrected refractive error has been one
of the major causes of visual impairment. There should be improved
planning to reduce the burden of refractive error by health education,
school screening and community screening. Early diagnosis of the
refractive errors with easy availability of spectacles at affordable
prices appears to be the most effective method to address the problem
of low vision for many people. Other causes of visual impairment like
corneal opacities and glaucoma can also be reduced by proper
screening in eye camps. In conclusion, we would argue that in Nepal
(with its relatively low health awareness) this aspect of eye care
activity in low vision needs to be strengthened and prioritized by
policymakers.
References
bamashmus, m. a. & al-akily, s. a. (2010) ‘Profile of Childhood Blindness and Low
Vision in Yemen: A Hospital-based Study’, Eastern Mediterranean Health
Journal 16: 425–8.
brilliant, g. e., pokhrel, r. p., grasset, n. c. & brilliant, l. b. (1988) The
Epidemiology of Blindness in Nepal: Report of the 1981 Nepal Blindness
Survey. Chelsea, MI: The Seva Foundation.
elfadul mohamed, i. a. & binnawi, k. h. (2009) ‘Low Vision Devices in Sudanese
Children’, Sudanese Journal of Ophthalmology 1: 37–40.
kc, b. k., thapa, h. b., gurung, s., sherchan, a., karthikeyan, a. s. & kandel, r. p.
(2007) ‘Hospital Based Study on Causes of Low Vision and Patient Preference
for Different Types of Low Vision Devices’, Journal of Institute of Medicine
29(2): 19–24.
nepal facts and figures (2010) The Fred Hollows Foundation. Available at: http://
www.fredhollows.org (accessed 10 April 2010).
nepal life expectancy at birth (2010) Available at: http://www.indexmundi.com/
nepal/life_expectancy_at_birth.html
nepal netra jyoti sangha report (2002) National Low Vision Program. Available
at: www.nnjs.org.np
mohidin, n. & yusoff, s. (1998) ‘Profile of a Low Vision Clinic Population’,
Clinical and Experimental Optometry 81(5): 198–202.
paudel, p., khadka, j. & sharma, a. (2005) ‘Profile of a Low Vision Population’,
International Congress Series – Proceedings of the International Congress
Vision 1282: 252–6.
at HINARI on September 2, 2011jvi.sagepub.comDownloaded from
THE BRITISH JOURNAL OF VISUAL IMPAIRMENT 29(3)
226
siddiqui, a., bäckman, ö. & awan, h. r. (1997) ‘Multidisciplinary Approach in the
Development of Comprehensive Low-vision Services in Developing
Countries’, Eastern Mediterranean Health Journal 3(1): 149–53.
thylefors, b. (1998) ‘A Global Initiative for the Elimination of Avoidable
Blindness’, American Journal of Ophthalmology 125: 90–3.
who (1993) The Management of Low Vision in Children. Report of a WHO
Consultation: Bangkok, 1992. Geneva: World Health Organization.
Available at: www.who.int/ncd/vision2020.../WHO_PBL_91.23_Rev.1.pdf
who (2004) VISION 2020: The Right to Sight – The Global Initiative for the
Elimination of Avoidable Blindness. Magnitude and Causes of Visual Impairment.
Fact Sheet No. 282. Geneva: World Health Organization. Available at: http://
www.who.int/mediacentre/factsheet s/fs282/en/index.html (accessed 20
October 2005).
who (2005) Prevention of Blindness and Visual Impairment. Available at: http://
www.who.int/blindness/en/ (accessed 20 October 2005).
who (2009) Visual Impairment and Blindness. World Health Organization. Fact
Sheet No. 282. Available at: http://www.who.int/mediacentre/factsheets/
fs282/en/
unfpa (2011) Thematic Areas of UNFPA’s Programmes in Nepal: Gender.
Available at: http://nepal.unfpa.org/en/programmes/gender.php
ajit kumar thakur
Optometrist, Mechi Eye Hospital, Anarmani-7, Jhapa, Nepal.
Email: ajitfriend2002@yahoo.com, ajitfirend2002@gmail.com
at HINARI on September 2, 2011jvi.sagepub.comDownloaded from
... Another study in Nigeria found that 19.2% of patients were between 10-19 years old [21]. In addition to the mentioned studies from developing countries, further studies in Korea [25], Malaysia [26], and Nepal [27][28][29] found that the highest percentage of service users were from younger age groups. ...
... In another Australian study, Jamous further concluded that ophthalmologists mainly referred patients to low-vision rehabilitation clinics, while optometrists tended to refer most of their patients to the ophthalmologists themselves [37]. An additional study from low-vision clinics in the eastern region of Nepal found that 87.98% of the cases were referred from the eye-care professionals, while 8.66% were referred from schoolteachers and 2.71% were referred from community-based rehabilitation (CBR) [27]. ...
... A study done by Mohidin and Yusof found that retinitis pigmentosa caused the highest percentage of the ocular pathologies for patients aged between 30-59 years old, followed by macular dystrophy and diabetic retinopathy [26]. Another study found that retinitis pigmentosa was the most common cause of low vision in the age group 15-60 years and was the second most common cause in the whole population after refractive errors and amblyopia [27]. A third study stated that 16.6% of ocular issues were caused by retinitis pigmentosa, followed by age-related macular degeneration, then albinism [21]. ...
Article
Full-text available
The aim of this paper is to study the profile of persons with low vision in Jordan based on the clinical records of service users who attended the Vision Rehabilitation Center (VRC) at the German Jordanian University (GJU). A retrospective study was conducted by reviewing the archived data for persons with low vision attending the VRC over the period September 2012 to December 2017. The information collected included age, gender, referral, geographical distribution, chief functional visual problems, and ocular pathology. The records of 725 (28.9 � 20.3 years old) persons out of 858 persons were analyzed. Almost half (50.6%) of the sample was less than 18 years old. The main cause of the low vision was retinal diseases (53.4%), followed by albinism. Gender and age showed no significant influence on ocular pathology distribution. For the referrals, ophthalmologists (37.8%) were the largest source of referral, followed by institutions for people with disabilities (14.9%). Near tasks were reported as the main functional problems for patients with low vision (74.9%), followed by distance tasks (8.3%). This study sets a precedent for determining the characteristics of persons with low vision in Jordan. Developing an efficient referral system between eye health care professionals and other health caregivers is important to ensure the best multidisciplinary services for low vision.
... Due to varying definitions and methods of assessments, the epidemiology of low vision is not established. 26,27 In Nepal, the prevalence of low vision is estimated to be 0.7%. 28 Previously, best corrected visual acuity i.e. after best refractive correction was used to define visual impairment. ...
... In 16 (84.21%) optical labs, technicians were doing the edging manually; in other three labs they used both manual and automated edging techniques.26 Gap between need and availability of infrastructure and HR for refraction servicesNumber of refractions by types of refraction facility is shown in the box plot. ...
Thesis
Full-text available
Purpose: Purpose of this study was to determine the type, scale and level of refractive error services available in the central region of Nepal. Materials and methods: This was a descriptive cross-sectional study, which included desk review, key informants interview and primary data collection through observational visits. Stratified simple random sampling technique was used to select 50% of the primary eye care centres (PECC), eye hospitals, and eye departments of multispecialty hospitals. Data on infrastructure, human resources, efficiency of refractionists, methods of provision of refraction services, and cost and price of refraction services was collected from 29 centres by face to face interviews with 29 managers and 50 refractionists. Both qualitative and quantitative methods were used for data collection using semi-structured questionnaire and on-site observation checklists. Data were analysed using Stata /IC (version 12.1). Arc GIS 10.2 software was used to map the human resources. Results: Mean number of refractions per facility per year was 9,000 (IQR: 6,000 to 14,500). Total number of refractions carried out in the central region per year was 653,176. Unmet need for refractions was 1,323,234. Median minimum price for refraction was NRS 40 (IQR: NRS 30 – NRS 70). Median minimum cost for +/- 1 D lens was NRS 50 (IQR: 35 to 60). Median minimum cost and price of single vision prescription spectacles were NRS 205 (IQR: 160 to 250) and NRS 225 (IQR: 350 to 600) respectively. Conclusion: There is a huge unmet need for infrastructure and human resources for refraction services in the central region of Nepal. The distribution of the available services is highly uneven. More refractionists need to be trained taking care of their career prospects. To make refraction services more affordable and accessible, refraction services should be integrated to the primary health care, and frequent and systematic outreach programmes should be organized. Key Words: Human resources, Nepal, Refractive errors
... Even in China, it was reported that 10% of the older adults aged 50 years and above suffered from VI (Pan et al. 2016). This indicates that aging is one of the risk factor of VI, an age-related disease that occurs among older adults (Thakur et al. 2011). ...
Article
Full-text available
With an aging population, prevalence of visual impairment (VI) is expected to increase as well. A retrospective study was conducted involving the files of older adult patients aged 60 years and above from the Primary Eye Care (PEC) Optometry Clinic Universiti Kebangsaan Malaysia (UKM). This study was aimed to determine the prevalence and causes of VI among older adults. This retrospective study was conducted by reviewing files of older adult patients aged 60 years and above who had visited PEC Optometry Clinic UKM from 2009 to 2019. Socio-demographic, health status, status of visual acuity (VA), refractive error, prevalence and causes of VI before and after refractive correction were analysed by using descriptive statistic. Habitual distance VA was measured monocularly using the Snellen chart and recorded in decimal unit. The mean habitual distance VA in the better eye was 0.72+0.31, ranging from 0.41 to 1.03 while the mean VA after subjective refraction in the better eye was 0.88+0.28 which ranging from 0.60 to 1.16. The prevalence of VI based on habitual VA were 16.0%. The main cause of VI based on habitual VA was cataract (53.4%). The refractive status after subjective refraction showed highest percentage of hyperopia (41.9%), followed by emmetropia (32.4%) and myopia (25.7%). The findings of this study emphasise the importance of increased patient education and further expansion of optometric services are required to reduce avoidable blindness.
... Kajian lepas melaporkan kanak-kanak penglihatan terhad mengalami kesukaran dalam melakukan aktiviti hidup seharian (ADL) seperti mengecam wajah, membaca tulisan di papan hitam, membaca buku, mengenal pasti wang dan keupayaan dalam orientasi dan mobiliti (Byoumi & Ahmed 2013;Gothwal et al. 2003;Thakur et al. 2011). Keupayaan kanak-kanak penglihatan terhad melakukan ADL secara kendiri adalah penting untuk interaksi sosial dan seterusnya meningkatkan peluang mereka hidup berdikari di masa akan datang (Gothwal 2007). ...
... 1,2 The maximum burden of URE lies in South Asia. 2 Similar to other low-and middle-income country (LMIC) settings, URE including uncorrected presbyopia is a major public health problem in Nepal. [3][4][5][6] However, a little priority has been given to address refractive error-related vision impairment. Nepalese eye care system is rather cataract focused. ...
Article
Purpose : Although refractive error is the commonest ocular abnormality and the commonest cause of global visual impairment, qualitative studies exploring the impact of refractive error in people’s lives are sparse. This study was therefore carried out to explore the impact of refractive error on quality of life. Methods : We conducted 101 semi-structured in-depth interviews with people having refractive error, with or without corrections. Purposive sampling was applied to capture issues of people with diverse spectrum of refractive error. The interviews were recorded, transcribed and analysed using NVivo Software, Version 11 (QSR International Pty Ltd.). The thematic analysis was done using both inductive and deductive processes. We compared quality of life issues among people with various types of refractive error and among people with different refractive corrections. Results : The median age of the participants was 29 (range: 18 to 74) years. More than half were male (n=55) and myopes (n = 56). Almost one fifth were surgical emmetropes (n = 19). Twenty-nine participants had presbyopia. Nearly half of the participants (n = 47) had uncorrected refractive error. In regards to the refractive correction, sixty participants used glasses to varying frequency. Similarly 20 had surgical correction and 17 used contact lenses. During thematic analysis, 3,477 comments were coded into 381 nodes under 8 broad themes: Convenience, Activity limitations, Health concerns, Psychosocial well-being, Economic well-being, Visual symptoms, Ocular comfort-symptoms and General symptoms. Inconveniences wearing glasses was the most important issue in glasses wearers. Whereas, possibilities of having side effects or complications were the major concerns for participants wearing contact lenses. Similarly, concerns regarding the possibility of having to wear glasses again due to relapse of refractive error were the major concerns for the participants who had refractive surgery. For participants with uncorrected refractive error, activity limitations and symptoms were the most important issues. Conclusions : This study enriches the understanding of issues important to people with uncorrected and different types of refractive corrections. The quality of life issues identified in this study will be used to develop item banks to measure refractive error specific quality of life for developing country setting. This is an abstract that was submitted for the 2017 ARVO Annual Meeting, held in Baltimore, MD, May 7-11, 2017.
... Other causes were optic atrophy (7.7%), aphakia due to congenital cataract (7.7%), age related macular degeneration (7.7%), nystagmus associated with Retinal Detachment (7.7%). In a similar study done by., Thakur., et al. [16] (2011) in the same hospital settings had refractive error and amblyopia (24%) as the major ...
... 1,2 The maximum burden of URE lies in South Asia. 2 Similar to other low-and middle-income country (LMIC) settings, URE including uncorrected presbyopia is a major public health problem in Nepal. [3][4][5][6] However, a little priority has been given to address refractive error-related vision impairment. Nepalese eye care system is rather cataract focused. ...
Article
Purpose: The aim of this study was to explore the impact of corrected and uncorrected refractive error (URE) on Nepalese people’s quality of life (QoL), and to compare the QoL status between refractive error subgroups. Methods: Participants were recruited from Tilganga Institute of Ophthalmology and Dhulikhel Hospital, Nepal. Semi-structured in-depth interviews were conducted with 101 people with refractive error. Thematic analysis was used with matrices produced to compare the occurrence of themes and categories across participants. Themes were identified using an inductive approach. Results: Seven major themes emerged that determined refractive error-specific QoL: activity limitation, inconvenience, health concerns, psycho-social impact, economic impact, general and ocular comfort symptoms, and visual symptoms. Activity limitation, economic impact, and symptoms were the most important themes for the participants with URE, whereas inconvenience associated with wearing glasses was the most important issue in glasses wearers. Similarly, possibilities of having side effects or complications were the major concerns for participants wearing contact lens. In general, refractive surgery addressed socio-emotional impact of wearing glasses or contact lens. However, the surgery participants had concerns such as possibility of having to wear glasses again due to relapse of refractive error. Conclusion: Impact of refractive error on people’s QoL is multifaceted. Significance of the identified themes varies by refractive error subgroups. Refractive correction may not always address QoL impact of URE but often add unique QoL issues. This study findings also provide content for developing an item-bank for quantitatively measuring refractive error-specific QoL in developing country setting.
... 6 A few studies have been conducted and they conclude that around a third of the total number of people affected by low vision are children under the age of 15 years. 7,8 Knowledge of the local demographic data of children with visual impairment is critical for planning and delivering services to meet their needs. Knowing the status of paediatric visual impairment helps to form the policy for reducing childhood blindness and is necessary to formulate the policy for reducing childhood blindness. ...
Article
Full-text available
Childhood blindness and low vision have become major public health problems in developing countries. The purpose of this study was to categorise the causes of visual impairment according to aetiology and provide detailed local information on visually impaired children seeking low-vision services in a tertiary eye centre in Nepal. A retrospective study was conducted of all visually impaired children (visual acuity of less than 6/18 in the better eye), aged less than 17 years seen in the low-vision clinic at the Sagarmatha Chaudhary Eye Hospital in Lahan between January 1, 2012 and December 31, 2013. Of the 558 visually impaired children, the majority were males, 356 (63.7 per cent). More than half (56.5 per cent) of the children were in the 11 to 16 years age group. Many of the low-vision children (52.9 per cent) were identified as having moderate visual impairment (visual acuity less than 6/18 to 6/60). Most children were diagnosed with childhood (36.2 per cent) or genetic (35.5 per cent) aetiology, followed by prenatal (22.2 per cent) and perinatal (6.1 per cent) aetiologies. Refractive error and amblyopia (20.1 per cent), retinitis pigmentosa (14.9 per cent) and macular dystrophy (13.4 per cent) were the most common causes of paediatric visual impairment. Nystagmus (50.0 per cent) was the most common cause of low vision in the one to five years age group, whereas refractive error and amblyopia were the major causes in the six to 10 and 11 to 16 years age group (17.6 and 22.9 per cent, respectively). Many of the children (86.0 per cent) were prescribed low-vision aids and 72.0 per cent of the low-vision aid users showed an improvement in visual acuity either at distance or near. Paediatric low vision has a negative impact on the quality of life in children. Data from this study indicate that knowledge about the local characteristics and aetiological categorisation of the causes of low vision are essential in tackling paediatric visual impairment. The findings also signify the importance of early intervention to ensure a better quality of life.
... The current definition considers presenting visual acuity instead. 4,6,18,19 URE is the commonest cause of ocular morbidity and visual impairment in the primary, secondary and tertiary centres in Nepal. 3 Evidence-based planning of refraction services is hampered by a paucity of data. ...
Article
Full-text available
Uncorrected refractive error is a public health problem globally and in Nepal. Planning of refraction services is hampered by a paucity of data. This study was conducted to determine availability and distribution of human resources for refraction, their efficiency, the type and extent of their training; the current service provision of refraction services and the unmet need in human resources for refraction in Central Nepal. This was a descriptive cross-sectional study. All refraction facilities in the Central Region were identified through an Internet search and interviews of key informants from the professional bodies and parent organizations of primary eye centres. A stratified simple random sampling technique was used to select 50% of refraction facilities. The selected facilities were visited for primary data collection. Face-to-face interviews were conducted with the managers and the refractionists available in the facilities using a semi-structured questionnaire. Data was collected in 29 centres. All the managers (n=29; response rate 100%) and 50 refractionists (Response rate 65.8%) were interviewed. Optometrists and ophthalmic assistants were the main providers of refraction services (n = 70, 92.11%). They were unevenly distributed across the region, highly concentrated around urban areas. The median number of refractions per refractionist per year was 3600 (IQR: 2400 to 6000). Interviewed refractionists stated that clients' knowledge, attitude and practice related factors such as lack of awareness of the need for refraction services and/or availability of existing services were the major barriers to the output of refraction services. The total number of refractions carried out in the Central Region per year was 653,176. An additional 170 refractionists would be needed to meet the unmet need of 1,323,234 refractions. The study findings demand a major effort to develop appropriately trained personnel when planning refraction services in the Central Region, and in Nepal as a whole. The equitable distribution of the refractionists, their community-outreach services and awareness raising activities should be emphasized. © 2015 The Authors Clinical and Experimental Optometry © 2015 Optometrists Association Australia.
Article
OBJECTIVE:to analyze the regulations regarding the issue of eye care in the country, as an important and key aspect in the study of the potential access to services for low vision rehabilitation in Colombia. METHODOLOGY: a qualitative, descriptive study that approached the visual health policies while taking into account the theoretical model proposed by Andersen et al. A total of 38 interviews with professionals in health service-providing institutions and government agencies were conducted in six Colombian cities. The analysis, took into account the stages of the policy and the interviews were analyzed using the methodological design proposed by Taylor & Bogdan. RESULTS :low-vision is invisible for visual health policies. This has a negative effect on the recognition of it as a social problem that needs to be addressed, therefore the general system for social security in health has no coverage of any sort for rehabilitation. CONCLUSION: the absence of specific initiatives for vision rehabilitation becomes a barrier that prevents people with low vision from accessing eye care services and from obtaining optical and visual aids. This in turn has a negative effect on the quality of life of this population group.
Article
Full-text available
Background: In accordance with the objectives envisaged by the Vision 2020 WHO global initiative, this study was designed to reveal the causes of low vision (LV), patient preference for and acceptance of specific types of low vision devices. The study was performed between January, 2006 and December, 2006 at the Low Vision Clinic in Lumbini Eye Institute (LEI). Materials and Methods: A descriptive clinical study of patients with low vision was performed. All patients were examined by an Ophthalmologist and an Optometrist. Un-corrected visual acuity (VA), best-corrected visual acuity (BCVA), visual loss based on anatomical sites, low vision assessment was performed and patient preference for a specific low vision device was observed and documented. Standard National Low Vision Assessment Form was used. Results: A total of 166 new Nepali patients were included in the study out of whom 70% were male. Of these patients, lens related causes like aphakia, pseudophakia was the main cause of low vision in 35.55% patients, followed by refractive errors / amblyopia accounted for 19.23%, retinitis pigmentosa for 10.84%, whole globe abnormalities 10.25%, corneal pathology accounted for 7.24%, retinal disease (different types of maculopathies, retinal scars, retinal hemorrhages, vein occlusion, etc.) in 6.64%, and other causes (albinism, nystagmus, different syndromes, etc.) in 10.25%. In low vision assessment, 6.02 % not needed any device (sufficient near vision enough to conduct his or her near task without any type of devices / glasses) as per the guidelines set up by National Low Vision Programme), distance glasses gave enough improvement for 19.27%, spectacle magnifier was preferred by 51.80%, other magnifiers (hand/stand/dome) was preferred by 12.65%, and monocular handheld telescope was preferred by 20.48% for distance. The above includes certain patients requiring assistance with both near and distance vision who opted for multiple LV devices (i.e., for near and distance vision separately) instead of LV devices with multiple functionality. In non-optical Low-vision devices, 25 % preferred reading lamp, 10 % preferred reading stand, 12% preferred black felt tip pen, 6 % preferred sunglasses, 7 % preferred peaked cap, 4 % preferred typoscope, and 3 % preferred LV note book. Conclusion: Lens related causes and refractive errors/amblyopia seem to be two of the most important causes of low vision and should not be overlooked. In addition, low vision devices with a usage similar to that of spectacles were preferred by patients for near and telescope for distance. Keywords: Visual impairment, low vision devices, patient preference, causes of low vision.
Article
Full-text available
The main purpose of the study is to assess the cause of low vision and types of low vision devices prescribed over the period of 20 months. A retrospective study of 114 patients examined at BPKLCOS low vision clinic over the period of 20 months was reviewed and information was extracted. Age and gender, education and occupation, house location, cause of visual impairment and types of low vision devices prescribed were analyzed. The majority of patients (58%) were from the younger age groups less than 30 years of age. Older age group more than 65 years comprised of 15%. A significant numbers of low vision patients were of pediatric age group (29%). 69% patients were male and 31% were female. Male were found to be predominant in all age groups. The major cause of low vision was found to be diabetic retinopathy (15.8%) followed by macular diseases (13.2%), ARMD (10.5%), Retinitis Pigmentosa (9.6%) and Amblyopia (8.8%). The commonest low vision device prescribed was spectacle magnifier (34.9%) followed by hand-held magnifier (18.5%). The majority of low vision patients were of younger age groups. However, the main cause of low vision was diabetic retinopathy. Males were found to seek low vision service much more than females. The commonest low vision device prescribed was spectacle magnifier. D 2005 Elsevier B.V. All rights reserved.
Article
Full-text available
ABSTRACT A retrospective review of records determined the frequency and causes of low vision and blindness in all children aged < 16 years attending an ophthalmic practice in Sana'a, Yemen between January and December 2001. Of the 1104 children studied, 45 (4.1%) were found to have bilateral blindness and 115 (10.4%) were unilaterally blind; 48 children (4.3%) were bilaterally visually impaired and 109 (9.9%) were unilaterally visually impaired. The main causes of bilateral blindness included cataract, glaucoma and retinal disorders. The most common causes of bilateral low vision included refractive errors, keratoconus and retinal disorders. These results provide a basis for planning blindness prevention programmes in Yemen.
Article
Background: Causes of low vision and types of low vision devices (LVDs) prescribed in other low vision clinics have been studied extensively. Similar studies have not been conducted in Malaysia. This paper reports the results of a retrospective study of 573 patients seen at the Universiti Kebangsaan Malaysia-Malaysian Association for the Blind (UKM-MAB) low vision clinic in Kuala Lumpur. Methods: The record cards of 573 patients seen at the UKM-MAB clinic over 10 years were examined and the following information extracted: date of first consultation, age, sex, cause of visual impairment as diagnosed by an ophthalmologist and types of low vision devices (LVDs) prescribed. Results: The majority of patients were from the younger age groups with 423 (73.8 per cent) less than 50 years of age. Three hundred and ninety-five (68.9 per cent) of the subjects were males and 178 (31.1 per cent) female. The main causes of low vision were congenital structural defects including nystagmus among patients in the zero to 29 years age group, retinitis pigmentosa among the 30 to 59 years age group and age-related macular degeneration (ARM) among those over 60 years of age.
Low Vision Devices in Sudanese Children kc, b. k., thapa, h. b., gurung, s., sherchan, a., karthikeyan, a. s. & kandel, r. p. (2007) 'Hospital Based Study on Causes of Low Vision and Patient Preference for Different Types of Low Vision Devices
  • Elfadul Mohamed
elfadul mohamed, i. a. & binnawi, k. h. (2009) 'Low Vision Devices in Sudanese Children', Sudanese Journal of Ophthalmology 1: 37–40. kc, b. k., thapa, h. b., gurung, s., sherchan, a., karthikeyan, a. s. & kandel, r. p. (2007) 'Hospital Based Study on Causes of Low Vision and Patient Preference for Different Types of Low Vision Devices', Journal of Institute of Medicine 29(2): 19–24.
National Low Vision Program. Available at: www.nnjs.org.np mohidin, n. & yusoff, s
nepal life expectancy at birth (2010) Available at: http://www.indexmundi.com/ nepal/life_expectancy_at_birth.html nepal netra jyoti sangha report (2002) National Low Vision Program. Available at: www.nnjs.org.np mohidin, n. & yusoff, s. (1998) 'Profile of a Low Vision Clinic Population', Clinical and Experimental Optometry 81(5): 198-202.
The Epidemiology of Blindness in Nepal: Report of the 1981 Nepal Blindness Survey. Chelsea, MI: The Seva Foundation. elfadul mohamed, i. a. & binnawi, k. h
brilliant, g. e., pokhrel, r. p., grasset, n. c. & brilliant, l. b. (1988) The Epidemiology of Blindness in Nepal: Report of the 1981 Nepal Blindness Survey. Chelsea, MI: The Seva Foundation. elfadul mohamed, i. a. & binnawi, k. h. (2009) 'Low Vision Devices in Sudanese Children', Sudanese Journal of Ophthalmology 1: 37-40.
Available at: www.who.int/ncd/vision2020.../WHO_PBL_91.23_Rev.1.pdf who (2004) VISION 2020: The Right to Sight-The Global Initiative for the Elimination of Avoidable Blindness. Magnitude and Causes of Visual Impairment. Fact Sheet No. 282. Geneva: World Health Organization
  • B Thylefors
thylefors, b. (1998) 'A Global Initiative for the Elimination of Avoidable Blindness', American Journal of Ophthalmology 125: 90-3. who (1993) The Management of Low Vision in Children. Report of a WHO Consultation: Bangkok, 1992. Geneva: World Health Organization. Available at: www.who.int/ncd/vision2020.../WHO_PBL_91.23_Rev.1.pdf who (2004) VISION 2020: The Right to Sight-The Global Initiative for the Elimination of Avoidable Blindness. Magnitude and Causes of Visual Impairment. Fact Sheet No. 282. Geneva: World Health Organization. Available at: http:// www.who.int/mediacentre/factsheet s/fs282/en/index.html (accessed 20 October 2005).