Nearsightedness is estimated to affect around 40% of adults in the United States, and this number is expected to grow over the coming decade. The vast majority of these people use prescription lenses to correct their vision so that they can see clearly, but another, newer option has emerged that doesn’t only create clear vision, but that also helps to manage their nearsightedness so that it doesn’t get progressively worse. This treatment is called orthokeratology, or ortho-k for short.