Photorefractive Keratectomy Fig 518d

Principle: Tissue is ablated to change the corneal curvature and to achieve a refractive correction. Flattening the corneal curvature corrects myopia, whereas steepening the curvature corrects hyperopia. The amount of tissue removed at different sites can be varied with layer-by-layer excimer laser ablation and the use of apertures. This makes it possible to correct for myopia, by removing more tissue from the center of the cornea, or for hyperopia, by removing more tissue from the periphery.

Indications: Best results are achieved in correcting myopia of less than 6 diopters. At present stable correction can be achieved in 85 - 95% of all cases of myopia up to !6 diopters, with deviation of ±1 diopter from the target within one year. Correction of hyperopia has also been attempted.

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Diabetes 2

Diabetes 2

Diabetes is a disease that affects the way your body uses food. Normally, your body converts sugars, starches and other foods into a form of sugar called glucose. Your body uses glucose for fuel. The cells receive the glucose through the bloodstream. They then use insulin a hormone made by the pancreas to absorb the glucose, convert it into energy, and either use it or store it for later use. Learn more...

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