Global Blindness Nicholas Seeliger M D Global Blindness

Global Blindness Nicholas Seeliger, M. D.

Global Blindness n n Distribution of Blindness Cataract Vitamin A Deficiency Tropical Eye Diseases

Global Blindness n Distribution of Blindness 90% of the worlds blind live in the developing world n Over 2/3 rd of the cases are preventable / treatable n Every 5 seconds one person goes blind n Every 1 minutes one child goes blind n

Global Blindness n Cataracts and Blindness n Dominating cause of Global Blindness Reports as high as 50% n Estimated 18 million people n Treatable at relatively low cost n Self-sustaining low cost cataract surgery programs exist on the Indian subcontinent n Cheap manufacture of intraocular lenses has transformed outcomes n

Global Blindness n Cataracts and Blindness n Cataract Latin = Waterfall n Clouding of crystalline lens n Varying in degree of opacification n

Global Blindness n Cataracts Recent publications with twins indicated over 50% of risk due to genetics n Environmental risk is weak n Age, UV exposure, diabetes, tobacco, ect. n Drugs n n Corticosteriods ? Zetia Seroquel (CATIE study 2006)

Global Blindess n Cataracts & Blindness Increasing numbers blind because of demographics n Surgeries not keeping up n Treatment is surgical n ECCE (extracapsular cataract extraction) n High frequency sounds waves break up lens n Lens removed leaving capsule intact n Lens replaced with plastic lens n

Global Blindness n Cataracts and Blindness n Too few opthalmologists Developed nations: 1/10, 000 n Africa: 1/1, 000 n Similar patterns throughout developing world n Brain drain n

Global Blindness n Cataracts and Blindness n People’s Republic of China 22, 000 opthalmologists n 1/60, 000 for total population n Public Health Approach n High-Volume at Low Cost n

Global Blindness n Vitamin A Deficiency n n “Xeropthalmia” Discovered in early 1900’s by Mc. Collum Forgotten until “rediscovered” by Sommer in 1980’s Now understood as a major cause of childhood blindness and death n n Systemic features Mortality estimated at 1 -2. 5 million children / year

Global Blindness n What is Vitamin A? Retinol, its esters, and retinoic acid n From diet n fat-soluble ester in animal and dairy products n also carotene - naturally occuring precursor in certain fruits and veges n

Global Blindness n Vitamin A deficiency n Epidemiology Common where poor dietary intake of green leafy veges, eggs, milk n Preschool children / pregnant / lactating women most at risk n n n Estimated 500, 000 / year Who gets this in the US? n CF patients, post-op bowel surgeries, alcoholics, fad diets

Global Blindness n n Vitamin A Deficiency Results in: n Night Blindness n Earliest and most common sign of deficiency n n Conjunctival Xerosis n n Rhodopsin dependency on Vit A Abnormal tear secretion, loss of goblet cells resulting in keratomalacia and corneal scarring Bitot’s spots n Buildup of keratin debri in the conjuctiva

Global Blindness n Vitamin A Deficiency n Systemic Features Abnormal differentiation of epithelial cells n GI tract and Respiratory tract n Impair Immunity n n Consequences Increased diarrhea and malnutrition n Increased death from measles n Increased death from respiratory infections n

Global Blindness n Vitamin A Deficiency n Treatment n High-dose (200, 000 IU) 1 -2 times / year n n Food fortification n n Cost: 0. 02$ per capsule Rice, oils, milks, ect. Vitamin Angels n http: //www. vitaminangels. org/

Global Blindness n Tropical Eye Diseases n Trachoma n n 3 rd Leading cause of World Blindness Onchocerciasis River Blindness n 2 nd leading infectious cause n n Next time …