BLINDNESS
Presentation by
DR.VIOLET (de Sa) PINTO
Lecturer, Department of PSM
Objectives:
At the end of the session the student shall have
knowledge of : Blindness :definition, categories of visual impairment, its
causes and problem statement Changing concepts in healthcare with regards to eye
care Prevention of blindness :primary, secondary and tertiary
prevention Vision 2020
“Visual acuity of less than 3/60 (Snellen) or its equivalent.”
Non specialized personnel,
in absence of appropriate vision charts
“Inability to count fingers in daylight at a distance of 3 meters.”
Definition
CATEGORIES OF VISUAL IMPAIRMENT
If it is 6/18 or better = 0 or no visual impairment
Categories of visual impairment
Visual acuity
Maximum
< than
Minimum
= or > than
Low vision 1 6/18 6/60
2 6/60 3/60
Blindness 3 3/60 1/60(fingercounting at I
meter)
4 1/60(finger
counting at 1
meter)
Light perception
5 No light
perception
PROBLEM STATEMENT
Estimated 180 million people are visually disabled, nearly 45 million blind, 4 out of 5 living in developing countries.
Major causes…..cataract, glaucoma, trachoma, childhood blindness, onchoceriasis.
32% are aged 45-59 yrs, large majority 58% are over 60 yrs.
SEAR has 1/3rd of the world’s blind,50% of world’s blind children.
INDIA Causes of blindness Cataract 62.6% more with advancing age senile cataract- decade earlier Uncorrected 19.7% Refractive error Glaucoma 5.8% Posterior 4.7% segment pathology Corneal Opacity 0.9% Others 6.2% Injuries 1.2% cottage industry- carpentry, blacksmitty, stone crushing,
chiseling Congenital disorder, uveitis, retina detachment,tumours,diabetes,HT, diseases of nervous system, leprosy.
CHANGING CONCEPTS IN HEALTH CARE
Primary eye carePromotional & protection of eye health
On the spot treatment of commonest eye diseasesImprove coverage and quality
Establishment of National Prog.> Need for PHC approach
Team ConceptDeprofessionalisation
VHG, Ophthalmic assistant,MPW, Voluntary agencies
Epidemiological ApproachMeasurement of Incidence, prevalence,
risk factors of disease
AGENT-
Trachoma, Vit A def.
HOST-
Age- About 30% lose eyesight <20 yrs. children and young age group- refractive errors, trachoma, conjunctivitis, Vit A def. Middle age- Cataract, glaucoma& diabetes All ages, 20-40- accidents, injuries
Sex- trachoma, conjunctivitis, cataract-More in females, in India
EPIDEMIOLOGICAL DETERMINANTS
ENVIRONMENT-
Malnutrition- Vit A def.- even due to measles and diarrhoea PEM related- severe corneal destruction(keratomalacia)6mth- 3yrs.& 4 -6yrs.
Occupation – Cottage industry, workshops, factories, flying objects, gases.Doctors- x rays, u.v. rays, premature cataract
Social class – twice more prevalent in low social classes
EPIDEMIOLOGICAL DETERMINANTS
PREVENTION OF BLINDNESS
The concept of Avoidable blindness (preventable or curable) has gained recognition during the recent years.
Initial Assessment
Methods of Evaluation Intervention Primary care Secondary care Tertiary care Specific programmes Long term measures
Components for action in N.H.P.
1) INITIAL ASSESSMENT
Prevalence surveys – magnitude, distribution, causes
Setting priorities and development of appropriate intervention programmes.
2) METHODS OF INTERVENTION PRIMARY EYE CARE
Treatment and prevention at grassroot level by locally trained peripheral health worker. (VHG,MPW)
(acute conjunctivitis, opthalmia neonatrum,
trachoma, superficial foreign body, xeropthalmia)
Provided with essential drugs ; topical tetracycline, Vit A capsules, eye bandages, shields, etc.
Trained to refer difficult cases (eg. Corneal ulcer, penetrating foreign bodies, painful eye conditions & infections which do not respond to treatment) to nearest PHC & district hospital.
Promotion of personal hygiene, sanitation, good diet, safety in general.
Currently 1 VHG / 1000 population, 2 MPW / 5000 population.
SECONDARY CARE
Definitive management of common blinding conditions such as cataract, trichiasis, entropion, ocular trauma, glaucoma,etc.
PHC’s and district hospitals
where eye departments or eye clinics
are established.
Mobile clinics- Disadv- lacks permanence, adv- problem specific best use of local resource, provide inexpensive eye care
Eye camp approach- cataract, general eye health, surveys.
TERTIARY CARE
At National /Regional capitals, often associated with Medical colleges & institutes of medicine(National Institute for Blind, Dehradun)
Sophisticated eye care- retinal detachment , cornealGrafting
Eye banks- Maximum states passed Corneal grafting Acts
Education of blind in special schools and utilisation of their services (employment)
SPECIFIC PROGRAMMES
1) TRACHOMA CONTROL-
Endemic trachoma and associated infections, major cause of preventable blindness.
Early diagnosis and treatment Mass campaigns with topical teracycline Improvement of SE conditions TC Programme launched 1963. merged NBCP in 1976.
2) SCHOOL EYE HEALTH SERVICES- Screened & treated for refractive errors,
squint,ambylopia, trachoma H.E. – good posture, proper lighting, avoidance of glare,
angle between books and eye.
3) VIT A PROPHYLAXIS 2 lakh IU given 6 monthly 1-6 yrs.,
surveillance4) OCCUPATIONAL EYE HEALTH SERVICES Education, protective devices, improve safety
of machines, proper illumination, pre placement examination.
3) LONG TERM MEASURES1) Improving quality of life, modifying factors responsible for
persistence of eye health problems. Poor sanitation , lack of adequate safe water supplies,
increase intake of food rich in Vit A, lack of personal hygiene.
2) Health Education Create community awareness of the problem Motivate community to accept total eye health
programmes. To secure community participation.
4) EVALUATION Evaluation of objectives.
VISION 2020
“A global initiative to eliminate avoidable
blindness by WHO on 18th feb.1999.”
Objective: Assist member states in developing sustainable systems, which will enable them to eliminate avoidable blindness from major causes.
Plan of Action for country has following features:
Target diseases: Cataract, refractive errors, childhood blindness, glaucoma, diabetic retinopathy.
H.R.D. as well as infrastructure and technology developmnt. At various levels of health system.
Proposed 4 tier system
C.O.E. 20
Training centersTertiary care including retinal surg.,Corneal transplant. 200
Service Centers 2000Cataract SurgeryOthr common eye surg.Facilities for refractionReferral services
Vision Centers 20,000Refraction and prescription of glassesPrimary eye careSchool eye screening Screening and referral services
Prof. leadership, strategy.developmnt, CME,Standards,quality assurance, Research.
Prof. leadership, strategy.developmnt, CME,Standards,quality assurance, Research.
Thank You