[Application of duo-systems (piggy back) in correction of keratoconus].

The purpose of the paper was to determine possibilities and effectiveness of application of piggy back system in keratoconus and choosing the best soft contact lens to meet the demands of the system. 335 patients were examined (511 eyes), including 131 women (163 eyes) and 204 men (348 eyes). Retrospective method involved patients with chronic corneal erosion and symptoms of intolerance of hard contact lenses. It was found out that application of piggy back system is the best therapeutic method in cases of chronic corneal erosion and it improves comfort of wearing lenses. Sof Lens 66 proved to fulfill the assumed criteria best. Application of piggy back reduces opacity within keratoconus top and it prevents or delays necessity of penetrating keratoplasty.