Global BlindnessGlobal Blindness

Nicholas Seeliger, M.D.Nicholas Seeliger, M.D.

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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