EPIDEMIOLOGY OF BLINDNESS

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EPIDEMIOLOGY OF BLINDNESS

• BY
• VEENA M PILLAI

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DEFINITIONS

• BLINDNESSVISUAL ACUITY OF LESS THAN 3/60 OR ITS
  EQUIVALENT.
• LOW VISIONVISUAL ACUITY OF LESS THAN 6/ 18 BUT
  3/60 OR CORRESPONDING TO VISUAL FIELD LOSS TO
  LESS THAN 20 IN THE BETTER EYE WITH BEST
  POSSIBLE CORRECTION.
• AVOIDABLE BLINDNESSBLINDNESS WHICH COULD BE
  EITHER TREATED OR PREVENTED BY KNOWN
  COST-EFFECTIVE MEANS.

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THE PROBLEM

• WORLDWIDE 161 m PEOPLE ARE VISUALLY IMPAIRED-
  124m LOW VISION 37m BLIND
• ANOTHER 153m SUFFER FROM VISUAL IMPAIRMENT DUE TO
  UNCORRECTED REFRACTIVE ERRORS
• gt90 OF WORLDS VISUALLY IMPAIRED LIVE IN LOW AND
  MIDDLE INCOME COUNTRIES.
• EXCEPT IN MOST DEVELOPED COUNTRIES,CATARACT
  REMAINS THE MOST COMMON CAUSE OF BLINDNESS.

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• UPTO 75S OF ALL BLINDNESS IN ADULTS IS
  AVOIDABLE THROUGH PREVENTION AND TREATMENT.
• INFECTIOUS CAUSES HAVE DECREASED GLOBALLY .THE
  NUMBER OF PEOPLE AFFECTED BY BLINDING TRACHOMA
  HAS DECREASED FROM 360m TO 80m PRESENTLY.
• AN ESTIMATED 1.5m CHILDREN lt15 ARE BLIND OF
  WHICH 50 CAN BE AVOIDED BY EARLY TREATMENT OF
  DISEASE AND CORRECTING CAUSES AT BIRTH.

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CAUSES OF BLINDNESS

• IN DEVELOPED COUNTRIESACCIDENTS,GLAUCOMA,DIABETES
  , VASCULAR DISEASES(HYPERTENSION),CATARACT AND
  DEGENERATION OF OCULAR TISSUES ESP. OF THE RETINA
  AND HEREDITARY CONDITIONS.
• IN DEVELOPING COUNTRIES
• CATARACT-62.6
• REFRACTIVE ERRORS-19.7
• GLAUCOMA-5.8
• POST. SEGMENT DISORDER-4.7
• SURGICAL COMPLICATION-1.2

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• CAUSES OF CHILDHOOD BLINDNESS
• REFRACTIVE ERRORS,TRACHOMA,CONJUNCTIVITIS,
  XEROPHTHALMIA, CONGENITAL CATARACT , RETINOPATHY
  OF PREMATURITY.
• CAUSES OF AVOIDABLE BLINDNESS
• CATARACT,TRACHOMA,ONCHOCERCIASIS, CHILDHOOD
  BLINDNESS,REFRACTIVE ERRORS,GLAUCOMA,DIABETIC
  RETINOPATHY

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EPIDEMIOLOGICAL DETERMINANTS

• AGEMORE THAN 82 BELONGS TO THE GROUP OF gt50YRS.
• GENDERHIGHER IN FEMALES
• MALNUTRITIONVIT.A DEFICIENCY ,INFECTIOUS
  DISEASES OF NEW BORN.
• OCCUPATION
• SOCIAL CLASSHIGHER IN LOW SOCIO-ECONOMIC STATUS.
• GEOGRAPHICALgt90 IN DEVELOPING COUNTRIES( SE
  ASIA27)

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REASONS FOR HIGH PREVALENCE IN INDIA

• OVERALL RISE IN SIZE OF POPULATION
• LIFE EXPECTANCY HAS INCREASED
• MAJOR POPULATION IN RURAL AREAS HAVE POOR ACCESS
  TO EYE CARE FACILITIES
• INADEQUATE AVAILABILITY OF TRAINED HEALTH
  PERSONNALS INADEQUATE UTILIZATION OF AVAILABLE
  OPHTHALMIC SURGEONS
• POOR NUTRITIONAL STATUS OF MOTHER AND YOUNG
  CHILDREN
• ADVERSE ENVIRONMENTAL CONDITIONS AND DOMESTIC
  UNHYGIENE CONDITIONS.
• LACK OF COMMUNITY AWARENESS POOR HEALTH SEEKING
  BEHAVIOUR
• PREV. OF MYTHS MISCONCEPTIONS ABOUT SURGERIES.

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THANK YOU