Thus, a reduction in childhood myopia using OKL has been proofed in Asian children; however, weather similar result can be achieved in a group of children from Northern Europe is unknown. The influence of OKL on quality of life impact of refractive correction has never been investigated in a randomized trail. How OKL reduce the axial growth of the eye is unknown. The lenses induce multifocality and higher order aberrations in the cornea, which might change the peripheral defocus. A change in defocus has been suggested as a mechanism for controlling axial length growth.