You mean the heat in the outside deform your contacts. How does that happen? Wow, it's unbelievable. But...mmm, maybe it could happen. Er, I strongly suggest you to buy a pair of prescription sunglasses because prescription sunglasses can correct your vision problems as well as block harmful UV rays for your eyes. Plus, buy those sunglasses that can block 100% UV rays for you. They are good sunglasses. But maybe it will be a little inconvenient if you want to use sunglasses at home because the light is darker than that in the outside. And the tinted lenses will darker the environment so that you may find it difficult to see things clearly in the house. So you may need to buy a pair of prescription glasses too. Hope this helped!