2. What is the definition of Blindness?
The definition of Blindness under the National
Program for Control of Blindness (NPCB) –
has been modified in line with WHO
definition
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Presenting Visual acuity less than 3/60 in the better
eye and limitation of field of vision to be less than
10 degrees from the center of fixation
3. Other Definitions
1. Economic blindness : Level of blindness that prevents individual
from earning his wages.
2. Social blindness : is the degree of disability that hampers an
individual from socially interacting with the family and peers in
satisfactory manner.
3. Manifest blindness: Visual acuity, if 1/60 or just perception of
light in the better eye.
4. Absolute blindness : Inability to perceive light in the in an eye.
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4. Other Definitions
4. Curable blindness : Blindness is reversible by prompt
management. Eg: Cataract, blindness from refractive error.
5. Preventable blindness : Loss of vision that could have been
completely prevented by effective measures. Eg: xerophthalmia,
trachoma, glaucoma.
6. Avoidable blindness: Sum total- Curable blindness +Preventable
blindness . About 80% of blindness is avoidable.
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5. Categories of Visual Impairment
Presenting distance visual acuity
Category Worse than Equal to better than
Mild or no visual impairment 0 6/18
Moderate Visual Impairment 1 6/18 6/60
Severe visual impairment 2 6/60 3/60
Blindness 3 (Social blindness) 3/60 1/60*
Blindness 4 (Manifest
blindness)
1/60 Light perception
Blindness 5(absolute blindness) No light perception
9 Undetermined or unspecified
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*Or counts finger at one meter. A category 6-8, involves blindness of monocular
visual of various degrees.
6. What are the types of blindness
Comparison between WHO and NPCB
WHO NPCB
Cat 1 = Low Blindness
Cat 2 = Economic Blindness
Cat 3 = Social Blindness
Cat 4 = Manifest Blindness
Cat 5 = Absolute Blindness
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7. PROBLEM STATEMENT OF BLINDNESS-
WORLD
(WHO)
1.Globally, at least 2.2 billion people have a near or distance vision
impairment. In at least 1 billion of these, vision impairment could have
been prevented or is yet to be addressed.
2.The leading causes of vision impairment and blindness at a global level
are refractive errors and cataracts.
3.It is estimated that globally only 36% of people with a distance vision
impairment due to refractive error and only 17% of people with vision
impairment due to cataract have received access to an appropriate
intervention.
https://www.who.int/news-room/fact-sheets/detail/blindness-and-visual-im
pairment
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8. PROBLEM STATEMENT OF BLINDNESS-
WORLD
(WHO)
4. Vision impairment poses an enormous global financial
burden, with the annual global cost of productivity
estimated to be US$ 411 billion.
5. Vision loss can affect people of all ages; however, most
people with vision impairment and blindness are over the
age of 50 years.
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9. Causes
Globally, the leading causes of vision impairment and
blindness are:
a)Cataract (94 million)
b)refractive errors (88.4 million)
c)age-related macular degeneration (8 million)
d)Glaucoma (7.7 million)
e)diabetic retinopathy (3.9 million)
•The main condition causing near vision impairment is
presbyopia (826 million)
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11. Main causes of blindness in India
(NPCBVI)
1. Cataract: Accounts for approximately 66.2% of blindness cases among
individuals aged 50 years and above. NPCBVI
2. Uncorrected Refractive Errors: Significant contributor to visual
impairment, responsible for about 18.8% of moderate visual
impairment cases in the same age group. NPCBVI
3. Corneal Opacity: Contributes to approximately 8.2% of blindness
cases among individuals aged 50 years and above. PubMed
4. Glaucoma: Responsible for about 5.5% of blindness cases in the same
demographic
5. Posterior Segment Disorders: Account for 5.9% of blindness cases
among individuals aged 50 years and above. PubMed
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12. Main causes of blindness in India (NPCBVI)
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6. Diabetic Retinopathy: Emerging as a significant cause of visual
impairment, though specific prevalence data is limited.
7. Age-Related Macular Degeneration (ARMD): Responsible for 0.7% of
blindness cases among individuals aged 50 years and above. NPCBVI
8. Cataract Surgical Complications: Contribute to 7.2% of blindness cases in
the same demographic. PubMed
9. Childhood Blindness: Conditions such as retinopathy of prematurity
(ROP) are emerging as significant causes, especially with increasing
survival rates of preterm infants.
10. Trachoma: Has significantly declined in India due to improved sanitation
and public health measures, and it is no longer a leading cause of
blindness in the country.
18. Primary Prevention
Trained primary level (grass root ) level workers should provide
promotive and preventive services for eye care.
1.Health education of the community regarding eye care, hygiene and
sanitation, and frequent washing of eyes in trachoma endemic areas,
regarding proper nutrition especially in context of Vitamin A rich
foods, and availability of eye care services.
2.Upliftment of socioeconomic status, general standards of living, and
general conditions.
3.Nutritional supplementing program especially with Vitamin A.
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19. Primary Prevention
4. Fortification of certain foods with
Vitamin A ( addition of Vitamin A to
Dalda in India, Vitamin A fortification
with sugar, salt, tea, margarine and
dried –skimmed milk.
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20. Primary Prevention
5. Provision of eye care services , as a
part of primary healthcare system.
6. Personal protection using goggles or
eye shield in high-risk occupations.
7. Social actions during fairs and
festivals by keeping children at a
safe distance from places where
crackers are burst.
8. Health education of personal
hygiene of the eyes.
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21. Primary Prevention
9. Eyecare in neonatal care , including
cleaning of the eyes with sterile swabs,
followed by use of tetracycline drops or
freshly prepared silver nitrate solution for
the suspected neonates who are at risk of
ophthalmia neonatorum conditions.
10. Treatment of minor eye ailments such as
superficial foreign bodies, conjunctivitis,
etc.
11. Health promotive measures to prevent
eye complications due to diabetes
mellitus and hypertension by adopting
self care practices eg-maintaining Normal
blood sugar and blood pressure and early
detection of retinopathy.
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22. Secondary prevention
This includes Early diagnosis and treatment,
services provided by Medical Officers at Primary
health centres, with assistants of ophthalmic
Ophthalmic assistants and optometrists.
1.Cataract: Surgical removal of the opacified
lens followed by intraocular lens implantations is
the way to restore vision. Early diagnosis and
provision of surgery using eye camp approach is
the cornerstone.
2.Trachoma: The “SAFE” strategy includes
surgery, antibiotics, facial cleanliness, and
environmental improvements, has been
recommended by WHO to control trachoma.
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23. Secondary prevention
3. Glaucoma: Early diagnosis and
treatment are to be offered to
glaucoma patients to avoid
irreversible blindness.
4. Diabetic eye complications: Early
detection of diabetic eye
complications like cataract,
retinopathy by screening programs,
and referrals to higher centres for
the management of the
complications.
5. Refractive errors: early detection
of refractive errors though school
health programs and offering the
corrective glasses, which would also
improve the school performance by
children. These services should also
be provided on the primary
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24. Secondary prevention
6. Special screening examinations :
Retinopathy of prematurity and retinitis
pigmentosa are to be screened during early
childhood.
7. Vitamin A therapy for early stages of
Vitamin A deficiency
i. > 1yr of age : 200,000 IU Vitamin A
Orally/ IM
ii. <1 ye of age: 100,000 IU Vitamin A
Orally/ IM
repeated the following day and 4 weeks later.
Children less than 1 year of age and any age
less than 8kg- treated with half dose.
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25. Tertiary Prevention
1. Early detection of complications and rehabilitation.
2. Procedures includes
i. Retinal detachment Surgery
ii. Laser surgery for retinopathy and refractive errors
iii. Corneal grafting
iv. Corrective procedure for squints
The tertiary level of care is provided through super speciality
hospitals, medical colleges, national Institutes and High –tech
hospitals.
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26. Community Ophthalmology in India:
1. Community ophthalmology is a public
health branch focused on the
prevention, treatment, and
management of eye diseases at the
community level.
2. In India, 9 million blind, of which 85% is
curable and 45 million impaired ,
which affects millions and has
substantial socioeconomic
consequences.
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27. Community Ophthalmology in India:
Role of National Programs
India has implemented large-scale programs to
tackle blindness:
National Program for Control of Blindness and
Visual Impairment (NPCBVI):
i. Launched in 1976 with the aim of reducing
blindness prevalence to 0.3% by 2025.
ii. Focuses on free cataract surgeries, spectacles
for children, and primary eye care services.
iii. Promotes school vision screenings, community
awareness campaigns, and mobile units for
remote areas.
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28. Community Ophthalmology in India:
Primary Eye Care Delivery
1.Primary Health Centers (PHCs): Act as the first
point of contact for eye care.
2.Vision Centers: Provide basic diagnostic
services and referrals.
3.Community Outreach Programs:
1. Eye camps organized by NGOs and
government agencies.
2. Screening and surgeries performed in
underserved regions.
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29. Community Ophthalmology in India
Public-Private Partnerships
1.Organizations like Aravind Eye
Care, LV Prasad Eye Institute, and
Sankara Nethralaya work alongside
government initiatives.
2.Their models integrate high-
quality, affordable services with
outreach efforts to increase
accessibility.
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30. Strategies and Interventions
1.Cataract Surgery Camps
i.Mobile teams perform free or subsidized cataract surgeries in rural areas.
ii.Camps are instrumental in reducing cataract-related blindness.
2. School Eye Screening
i.Programs target early detection of refractive errors in children.
ii.Collaboration with schools ensures that spectacles are provided to those
in need.
3. Tele-Ophthalmology
i.Advances in telemedicine enable diagnosis and referrals in remote areas.
ii.Increases reach while reducing the need for specialized personnel on-
site.
4. Eye Banking and Corneal Transplants
i.India has established eye banks to address corneal blindness.
ii.Awareness campaigns encourage corneal donation.
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32. WHAT IS VISION 2020?
VISION 2020 is a joint global initiative by
WHO and IAPB
to ELIMINATE AVOIDABLE BLINDNESS in Member Countries
Right to Sight
33. World Sight Day
Celebrated 11th
October every year.
Advocacy event to focus global attention on
blindness and visual impairment and about
eye care to prevent them.
Coordinated by International Agency for the
Prevention of Blindness.
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34. World Glaucoma Awareness week
Celebrated from 11th
march to 17th
march
which is a silent painless contributor to
prevent from avoidable blindness.
Advocating people to have regular eye
check ups and prevent blindness.
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35. Eye Donation
Current Scenario:
1.Prevalence of Corneal Blindness: Approximately 1.1
million people in India are affected by corneal
blindness, with an additional 25,000 to 30,000 cases
reported annually. PMC
2.Eye Donation Rates: Despite the high demand, the
current annual number of corneal transplants is
around 25,000, indicating a substantial gap between
the need and availability of donor tissues. PMC
Key Organizations:
1.Eye Bank Association of India (EBAI): Established to
enhance eye banking services, EBAI has been
instrumental in scaling up eye donations and
harvesting to over 50,000 eyes annually. PMC
2.Sankara Eye Hospital: A notable institution that
operates eye banks and has performed over 1 million
free eye surgeries, contributing significantly to
reducing corneal blindness in India. PMC
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36. Eye Donation
Challenges:
i.Awareness and Misconceptions: Studies indicate that barriers to eye
donation are often due to misinformation rather than cultural or
religious beliefs. PMC
ii.Infrastructure Limitations: The need for a robust network of eye
banks and trained personnel to facilitate efficient eye donation and
transplantation processes.
How to Pledge Eyes:
i.Registration: Individuals can pledge their eyes by filling out a pledge
form and submitting it to the nearest eye bank. Many eye banks offer
online registration to simplify the process.
ii.Posthumous Donation: Eyes must be removed within 4-6 hours
after death; therefore, it's crucial for family members to inform the
nearest eye bank immediately upon the donor's demise.
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