I have small cateracts. Apparently they are common in people who have spend much time outdoors in desert climates. My opthalomologist keeps an eye on them, but says that until they interfere with my sight, don't worry. He checks every 6 months.
When they do start to be a problem, he will surgically remove them by laser. Laser surgery is a wonderful thing. My wife has had new implants and is back to better than 20-20. The province pays most of the tab, but the better soft lenses cost additionally about $500.

The lens surgery is nothing. While she had it done (one eye at a time is best) The eye was covered for about 3 days. The cateract surgery calls for the UV glasses.
Other medical conditions, if not eye related, should be no problem.