Global BlindnessGlobal Blindness
Distribution of BlindnessDistribution of Blindness CataractCataract Vitamin A DeficiencyVitamin A Deficiency Tropical Eye DiseasesTropical Eye Diseases
Global BlindnessGlobal Blindness
Distribution of BlindnessDistribution of Blindness 90% of the worlds blind live in the 90% of the worlds blind live in the
developing worlddeveloping world Over 2/3Over 2/3rdrd of the cases are preventable / of the cases are preventable /
treatabletreatable Every 5 seconds one person goes blindEvery 5 seconds one person goes blind Every 1 minutes one child goes blindEvery 1 minutes one child goes blind
Global BlindnessGlobal Blindness
Cataracts and BlindnessCataracts and Blindness Dominating cause of Global BlindnessDominating cause of Global Blindness
Reports as high as 50%Reports as high as 50% Estimated 18 million peopleEstimated 18 million people
Treatable at relatively low costTreatable at relatively low cost Self-sustaining low cost cataract surgery Self-sustaining low cost cataract surgery
programs exist on the Indian programs exist on the Indian subcontinentsubcontinent
Cheap manufacture of intraocular lenses Cheap manufacture of intraocular lenses has transformed outcomeshas transformed outcomes
Global BlindnessGlobal Blindness Cataracts and Cataracts and
BlindnessBlindness Cataract Cataract
Latin = WaterfallLatin = Waterfall Clouding of Clouding of
crystalline lens crystalline lens Varying in degree Varying in degree
of opacificationof opacification
Global BlindnessGlobal Blindness
CataractsCataracts Recent publications with twins indicated Recent publications with twins indicated
over 50% of risk due to geneticsover 50% of risk due to genetics Environmental risk is weakEnvironmental risk is weak
Age, UV exposure, diabetes, tobacco, ect. Age, UV exposure, diabetes, tobacco, ect. DrugsDrugs
CorticosteriodsCorticosteriods ? Zetia? Zetia Seroquel (CATIE study 2006)Seroquel (CATIE study 2006)
Global BlindessGlobal Blindess
Cataracts & BlindnessCataracts & Blindness Increasing numbers blind because of Increasing numbers blind because of
demographicsdemographics Surgeries not keeping upSurgeries not keeping up Treatment is surgicalTreatment is surgical ECCE (extracapsular cataract extraction)ECCE (extracapsular cataract extraction)
High frequency sounds waves break up lensHigh frequency sounds waves break up lens Lens removed leaving capsule intactLens removed leaving capsule intact Lens replaced with plastic lensLens replaced with plastic lens
Global BlindnessGlobal Blindness
Cataracts and BlindnessCataracts and Blindness Too few opthalmologistsToo few opthalmologists
Developed nations: 1/10,000Developed nations: 1/10,000 Africa: 1/1,000,000Africa: 1/1,000,000 Similar patterns throughout developing Similar patterns throughout developing
worldworld Brain drainBrain drain
Global BlindnessGlobal Blindness
Cataracts and BlindnessCataracts and Blindness People’s Republic of ChinaPeople’s Republic of China
22,000 opthalmologists22,000 opthalmologists 1/60,000 for total population1/60,000 for total population Public Health ApproachPublic Health Approach High-Volume at Low CostHigh-Volume at Low Cost
Global BlindnessGlobal Blindness
Vitamin A DeficiencyVitamin A Deficiency ““Xeropthalmia”Xeropthalmia” Discovered in early 1900’s by McCollumDiscovered in early 1900’s by McCollum Forgotten until “rediscovered” by Sommer in Forgotten until “rediscovered” by Sommer in
1980’s1980’s Now understood as a major cause of childhood Now understood as a major cause of childhood
blindness and deathblindness and death Systemic featuresSystemic features
Mortality estimated at 1-2.5 million children / Mortality estimated at 1-2.5 million children / yearyear
Global BlindnessGlobal Blindness
What is Vitamin A?What is Vitamin A? Retinol, its esters, and retinoic acidRetinol, its esters, and retinoic acid From dietFrom diet
fat-soluble ester in animal and dairy fat-soluble ester in animal and dairy productsproducts
also carotene - naturally occuring precursor also carotene - naturally occuring precursor in certain fruits and vegesin certain fruits and veges
Global BlindnessGlobal Blindness
Vitamin A deficiencyVitamin A deficiency EpidemiologyEpidemiology
Common where poor dietary intake of green Common where poor dietary intake of green leafy veges, eggs, milkleafy veges, eggs, milk
Preschool children / pregnant / lactating Preschool children / pregnant / lactating women most at riskwomen most at risk
Estimated 500,000 / yearEstimated 500,000 / year Who gets this in the US? Who gets this in the US?
CF patients, post-op bowel surgeries, alcoholics, CF patients, post-op bowel surgeries, alcoholics, fad dietsfad diets
Global BlindnessGlobal Blindness
Vitamin A DeficiencyVitamin A Deficiency Results in:Results in:
Night Blindness Night Blindness Earliest and most common sign of deficiencyEarliest and most common sign of deficiency
Rhodopsin dependency on Vit ARhodopsin dependency on Vit A
Conjunctival XerosisConjunctival Xerosis Abnormal tear secretion, loss of goblet cells resulting Abnormal tear secretion, loss of goblet cells resulting
in keratomalacia and corneal scarringin keratomalacia and corneal scarring Bitot’s spotsBitot’s spots
Buildup of keratin debri in the conjuctivaBuildup of keratin debri in the conjuctiva
Global BlindnessGlobal Blindness
Vitamin A DeficiencyVitamin A Deficiency Systemic FeaturesSystemic Features
Abnormal differentiation of epithelial cellsAbnormal differentiation of epithelial cells GI tract and Respiratory tractGI tract and Respiratory tract Impair ImmunityImpair Immunity
ConsequencesConsequences Increased diarrhea and malnutritionIncreased diarrhea and malnutrition Increased death from measlesIncreased death from measles Increased death from respiratory infectionsIncreased death from respiratory infections
Global BlindnessGlobal Blindness
Vitamin A DeficiencyVitamin A Deficiency TreatmentTreatment
High-dose (200,000 IU) 1-2 times / yearHigh-dose (200,000 IU) 1-2 times / year Cost: 0.02$ per capsuleCost: 0.02$ per capsule
Food fortificationFood fortification Rice, oils, milks, ect.Rice, oils, milks, ect.
Vitamin AngelsVitamin Angels http://www.vitaminangels.org/http://www.vitaminangels.org/
Global BlindnessGlobal Blindness
Tropical Eye DiseasesTropical Eye Diseases TrachomaTrachoma
33rdrd Leading cause of World Blindness Leading cause of World Blindness OnchocerciasisOnchocerciasis
River BlindnessRiver Blindness 22ndnd leading infectious cause leading infectious cause
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