Once you get LASIK, are you stuck with having a flap for life? Do PRK touchups get rid of the flap?

Hello there, 
LASIK flap do not ever go away, they just heal over. Frequently, they can be re-lifted, even years later, in case you need a touch up (an enhancement). Occasionally, however, an ophthalmologist who is doing an enhancement cannot re-lift the flap. In that case a PRK enhancement can be done. So the flap stays in place and the touch up is done right over it. Hope this answers your question. 
Good luck!
From NYC
Julia Giyaur , MD

The flap that is created during LASIK does not go away. The scars can become less and less visible with time underneath a microscope, but they are still present. PRK touch ups do not remove the flaps. 

The flap does not go away, which is a good thing. Although the flap is healed (sealed) in place, it can be lifted by your doctor years later to make for a quicker and easier touchup in the future if this is necessary.