This document discusses community ophthalmology and the prevention of blindness. It describes community ophthalmology as a shift from individualized eye care to a community-directed approach aimed at improving overall ocular health. Both hospital-based and community-based services are essential. The document also discusses defining and determining the magnitude of blindness, its leading causes globally and in Nepal, and approaches to control blindness through primary, secondary and tertiary prevention activities.

1. Community OphthalmologyCommunity Ophthalmology
J.B. ChandJ.B. Chand
Himalaya Eye HospitalHimalaya Eye Hospital
Pokhara, NepalPokhara, Nepal

2. Community Ophthalmology ?
– It represents a conceptual shift from
individualized eye care delivery system to
community directed approach aimed at the
improvement of the ocular health of the entire
community
– Comprehensive strategy for providing
Promotive, Preventive, Curative and
Rehabilitative eye care services to the
community

3. Blinding Eye Diseases
• Cataract
• Glaucoma
• Diabetic Retinopathy
– Occurs everywhere
– Affects Individuals
– Affects mainly adults
– Requires surgery/Laser
– Needs an eye doctor
• Hospital Based
• Trachoma
• Onchocerciasis
• Vit A deficiency
– Focal disease
– Affects Communities
– Starts in Children
– Require s medicine
– No need eye doctor
• Community Based
Both are Essential

4. Prevention of Blindness
Four important question to be asked when
considering prevention of blindness
– What is blindness? Definition
– How many are blind? Magnitude
– Why are people blind? Aetiology
– What can we do? Control

5. Definition of Blindness
• WHO has classified visual impairment and
blindness into various grade:
6/6-618 Normal vision
<6/18-6/60 Visual impairment
<6/60-3/60 Severe visual impairment
<3/60-NPL Blind
(Best available correction in the better eye)

6. An overview of the Blindness
• Many countries in the world have used
different definition for designating
somebody as blind in view of the
prevailing local conditions

7. Defining Blindness
• Economic Blindness:
– The level of blindness that prevents an individual from
earning his wages.
– Vision less then 6/60 with the better eye with best
correction
• Legal Blindness
– The level of blindness that necessitates welfare
measures and legal protection
– Vision less then 6/60 in better eye with best correction
and visual field less then 10 degree.

8. Defining Blindness..
• Social Blindness
– Hampers an individual from socially interacting with
the family and peer groups in a satisfactory manner
– Vision less then 3/60 with the better eye with best
correction
• Manifest Blindness
– Constraints the accomplishment of tasks for daily
living leading to impairment in mobility and
corresponding to a vision of 1/60

9. Defining Blindness..
• Absolute Blindness
– Inability to perceive light secondary to irreversible
damage to the nerve carrying the visual signals can
be classified as absolute blindness (optic atrophy)
• Curable Blindness
– The stage of blindness where the damage is
reversible by prompt management.
– Cataract is an example of curable blindness

10. Defining Blindness..
• Preventable Blindness
– The loss of vision that could have been completely
prevented by institution of effective preventive and
prophylactic measures
– Xerophthalmia and trachoma are the example of
preventable blindness
• Avoidable Blindness
– The sum total of preventable and curable blindness is
often referred to as avoidable blindness. 90% of
blindness in our country is avoidable

11. Defining Blindness..
• Incurable Blindness
– The stage of blindness that can not be
treated, prevented and cured and refers to
absolute blindness is called incurable
blindness. 5-10% of all blindness may fall in
this category.

12. Magnitude
• There are 161 million visually impaired
people in the world of which 37 million are
blind (WHO: 2002)
• Prevalence of the blindness is varies in
different part of world according to
economy and health care

13. Magnitude
Economy and
Health Care
%
Blind
Blind
Per Million
Good 0.25 2500
OK 0.50 5000
Poor 0.75 7500
Very poor 1.00+ 10000+

14. Global Causes of Blindness 2002
Causes %
Cataract 47.8
Glaucoma 12.3
ARMD 8.7
Corneal opacities 5.1
Diabetic retinopathy 4.8
Childhood blindness 3.9
Trachoma 3.6
Onchocerciasis 0.8
Other 13

15. Nepal: Causes of Blindness 1981
SN Causes %
1 Cataract 72
2 Retinal disease 3.3
3 Glaucoma 3.2
4 Other infection 3.2
5 Trachoma 2.4
6 Smallpox 2.2
7 Trauma 2.2
8 Amblyopia 1.3
9 Nutritional etiology 0.9
10 Miscellaneous 7.5
11 Undetermined 1.8
Total 100

16. Aetiology
• Asia:
– Cataract, Trachoma, Corneal disease, Glaucoma and
Vitamin A deficiency
• Africa:
– Cataract, Trachoma, Corneal disease, Glaucoma,
Vitamin A deficiency and Onchocerciasis.
• Latin America:
– Cataract, Glaucoma & Diabetic retinopathy
• North America and Europe:
– ARMD, Diabetic retinopathy &Glaucoma

17. Trends in Global Blindness
Year Number of Blinds (Millions)
1975 28
1984 31
1990 38
1995 35
2000 50?
2002 37

18. Causes of Increasing Blindness
• Increasing in population
• Increasing in life expectancy
• Inadequate eye care services
• Lack of awareness to seek eye care
services
• Poverty

19. Control
• Blindness can be control by the different
level of prevention
– Primary Prevention
– Secondary Prevention
– Tertiary Prevention

20. Primary Prevention
• To prevent the disease to ever occurring
• Example:
– VADX Good nutrition
– Trachoma Good water &
sanitation
– Rubella & measles Immunization

21. Secondary Prevention
• To prevent loss of vision from established
disease
• Example:
– Cataract Surgery
– Glaucoma Medical & surgical
– Diabetic retinopathy Medical & laser T/T
– Refractive error Spectacles
– Onchocerciasis Medical treatment
(Ivermectin)

22. Tertiary Prevention
• Restore vision to a blind person
• Example:
– Cataract Surgery
– Corneal scarring Keratoplasty
– Low vision Low vision aids

23. Where do Most blinds Live?
• Most blind people live in developing
countries
–India 9 million
–Africa 7 million
–China 6 million

24. Important Activities for PBL
• Every where:
– Cataract service delivery
– Screening and treatment of refractive error
• Focal diseases:
– Vitamin A supplementation and dietary counseling
– SAFE strategy for trachoma
– Ivermectin distribution for ochocerciasis
• Specialist service:
– Glaucoma
– Diabetic retinopathy
– Childhood blindness

25. Thank You