1. Corneal blindness in a
southern Indian population
Dr. Meenank. B
M.S. Ophthalmology (Post-Graduate )
ASRAM Medical College

2. Introduction
Blindness : Presenting distant visual acuity of < 6/ 60 (or) central vision < 20˚
in the better eye ( NPCB)
categories of visual impairment as per WHO (1977)
Category of visual
impairment
Level of visual acuity (Snellen)
Normal vision
Category 0
6/6 to 6/18
Low vision
category 1
6/18 to 6/60
category 2
6/60 to 3/60
Category 3
3/60 to 1/60 (or) V.F 5˚ and 10˚
Category 4
1/60 to PL⁺ (or) V.F less than 5˚
Category 5
NPL
Blindness

3. Major Causes of Blindness in India
Disease
Rapid Assessment of
Avoidable Blindness
(RAAB) 2006 -07’
National Program for
Control of Blindness
( NPCB ) 2001 -02 ‘
Cataract
72.2%
62.6%
Refractive errors
6.3%
19.7%
Glaucoma
4.4%
5.8%
Complications of cataract surgery
3.0%
1.0%
Corneal opacities including
trachoma
6.5%
0.9%

4. Corneal Blindness
Visual impairment and gross degree of visual loss occurring due to disease of
cornea
India – 25,000 to 30,000 / yr
Major causes of corneal blindness
Corneal Ulcers
Trachoma
Ocular injuries
Keratomalacia

5. Corneal blindness in a southern Indian population:
need for health promotion strategies
Dr Rakhi
R Dandona1,2 and L Dandona1
Dandona
1Centre for Social Services, Administrative Staff College of India, Hyderabad, India and
International Centre for Advancement of Rural Eye Care, LV Prasad Eye Institute,
Hyderabad, India
2Centre for Eye Research Australia, University of Melbourne, Melbourne, Australia
Journal – The British Journal of Ophthalmology (BJO)
Type – Peer review journal
Publisher – BMJ Publishing Group (United Kingdom)
ISSN no. – 0007-1161, 1468-2079
Impact factor – 2.725
Year, issue, volume, and page no. - 2003 February; 87(2): 133–141.
PubMed PMID: 12543736
PubMed Central PMCID: PMC1771511

6. Aim – To assess the distribution and cause of corneal blindness in a
population in southern India
Andhra Pradesh Eye Disease Study ( APEDS) states
A.P population – 76 million (2001) rural 73%
Age distribution
15yrs and below – 35.6%
16yrs to 29yrs – 25.7%
30 and above – 38.7%
objectives of APEDS
to determine the prevalence and causes of blindness and visual impairment
to determine the risk factors associated with major eye diseases
to determine the barriers to eye care services
to determine the quality of life in the visually impaired
prevalence of blind people in A.P -1.84%, of which 7% was due to corneal
diseases

7. Methods

8. Prevalence of corneal blindness
Participated – 10,293
Both eyes – 13
One eye – 73
Prevalence in four areas of APEDS combined and adjusted for age, sex, and
urban/ rural – 0.66%
95% CI – 0.49 to 0.86
Design effect – 1.35

9. Causes of corneal blindness
prevalence of corneal
blindness in all 4 areas of
APEDS irrespective of age,
sex, socio-economic status

10. Causes of corneal blindness in all 4 areas of APEDS
22 of 86 participants had trauma at-least in one eye
Factors
Urban
Rural
Percentag 5(31.8%)
e
15 ( 68.2%)
Age
<15yr
(71.4%)
>15yrs
(73.3%)
cause
Flying/
thrown
objects
Veg. matter
Incidence
42.9% @
playing
46.7% @
working

11. sex and urban-rural distribution
adjusted prevalence of the causes of corneal blindness
in at
least one eye for the different age groups for the four
areas of
APEDS combined
Corneal blindness
1.trauma and keratitis in
males 2.traditional
medicine and post
cataract Sx - females

12. Demographic associations of corneal blindness
None of the participants of upper socio-economic class have blindness due to
corneal disease
Visual acuity distribution
99 eye suffered from corneal blindness
26 eyes of 13 patients – B/l
73 eyes of 73 patients – U/l
< 20/200 to 20/400 – 9.1%
20/400 to PL – 39.4%
PL to NPL – 51.5%

13. Extrapolations to the population
Estimated A.P. population 2001 – 76 million
Extrapolated data from APEDS –
Atleast one eye – 50,160
Both eyes – 7600
Estimated Indian population 2001 – 1027 million
Extrapolated data from APEDS –
Atleast one eye – 6.8 million
Both eyes – 1 million
Prevalence - India by 2010 and 2020
2010 – 8.4 of 1168 million population
2020 – 10.6 of 1312 million population, will have corneal blindness

14. Discussion
The major causes of corneal blindness globally include –
Trachoma, corneal ulceration, Xerophthalmia, ophthalmia neonatorum,
traditional eye medicines, onchocerciasis, leprosy, and ocular trauma
These population based data suggest that 0.66% of this Indian population
suffers from corneal blindness in at least one eye i.e. one out of every 150
people

15. Prevalence and demographic
association
There was a regional variation in the prevalence of corneal blindness.
low prevalence in urban is due to the better socioeconomic status leading to
better nutrition and, thereby, reduced prevalence of vitamin A deficiency
associated with exanthematous fever.
People from rural areas with corneal blindness in both eyes have migrated to
urban areas thus. urban area had a high prevalence of corneal blindness

16. Causes of corneal blindness
Keratitis during childhood was the leading cause of corneal blindness in our
population
Malnourished children - debilitating fever - Vitamin A deficiency - blindness due to
xerophthalmia ( most common males)
Trauma was the second major cause of corneal blindness in our population - most
important causes of unilateral vision loss in developing countries ( most common
males 3:1)
Work place associated – 40%
Corneal scar following keratitis during adulthood was the next common cause of
corneal blindness in our population (50 years of age or more)
Recently, corneal ulceration has also been recognised as a “silent epidemic” in
developing countries
Corneal blindness related to cataract surgery - aphakic bullous keratopathy, females
had a 2.5 times higher risk

17. Role of corneal grafting
Most of the corneal blind cases can be visually rehabilitated by corneal grafting
Indications – V.A <20/200 to PL
Corneal grafting issues
Trained corneal surgeons with well equipped clinical facilities for proper surgery, long term
follow up, and treatment of graft rejections and other postoperative complications that might
occur, can successfully perform corneal grafting
The selection of a candidate for corneal grafting. Hospital based data on survival of corneal
grafts done at a reputed eye institute in India showed that the 5 year survival rate for corneal
transplants performed for the first time was 46.5% for all pathologies causing corneal
blindness
The third major issue is availability of adequate number of good quality donor corneas for
corneal grafting from reliable eye bank facilities
The fourth issue is that the surgical costs

18. Need for health promotion strategies
Of the 0.66% prevalence of corneal blindness in our population 95% were
avoidable
Prevention is more cost-effective as seen in some parts due to –
1. Corneal blindness due to Vit A def
2. Onchocerciasis
3. Leprosy
Health promotion programmers should be conducted mainly targeting risk
groups –
1. Schools
2. Factories
3. Universal immunization
Achieved through
Gov., non-gov., eye health professionals, health care promotional programmers which
focus on awareness, risk and consequence of corneal blindness and possible safety and
preventive procedures

19. Vision 2020 : To reduce prevalence of preventable and curable corneal
blindness
Strategies for control of corneal blindness
General Strategies
Disease specific Strategies
Eye injuries
Trachoma Blindness
Prevention of Xerophthalmia
Ban on traditional eye medication and quacks
Protective measures
Keratoplasty and Eye Banking