Typically, you can not tell just by looking with a microscope that a person has had PRK. In most cases, you can't tell just by looking with a microscope that a person has had Lasik either. Testing with topography will reveal the microscopic curvature changes caused by PRK or Lasik.
Being patient after PRK is by far the hardest part. Unfortunately, PRK healing can be exasperatingly slow in some cases. Most people are seeing a "weak 20/20" after 6 weeks, but many others are behind that schedule. Your progress up to this point does not reflect on how you will eventually see....
Unfortunately, there is no way to increase the thickness of your cornea. Corneal thickness is important for laser vision correction because in order to correct your vision, we need to sculpt/reshape the cornea with the laser - doing this results in the removal of corneal tissue. Larger glasses...