The main risk associated with Ortho-K is that of corneal infection. Corneal abrasions may occur when the lenses are not properly cleaned and particles rub against the cornea. If you are considering this as an option for your child, be aware of the sign of infections such as pain, discomfort, tearing, eye discharge, eye redness or sudden blurring of vision. When your child appears to be having any of these signs, do bring him/her to an ophthalmologist in case of infection. Apart from this, Ortho-K seemed to be a relatively safe option for managing myopia for children. You may want to take a look at this article for some useful information: http://www.todayonline.com/daily-focus/health/braces-eyes?singlepage=true