There have been tremendous advances in refractive surgery technology and technique since 1994. The difference could be measured in light years. Whether or not these advances mean additional surgery would be appropriate could only be determined after a comprehensive evaluation from a competent
eye doctor.
Your progressive myopia (nearsighted, shortsighted) vision may not be entirely because of regression from your PRK. As we age age there are many changes in the natural crystalline lens within the eye. One of the first noticeable changes is presbyopia, which is the lens becoming less able to focus on objects near and reading glasses become necessary. Another natual change is the development of cataracts.
An early stage of cataract development is a thickening of the center of the crystalline lens. This thickening can induce myopia and is often called "second sight" because myopia better allows you to see objects near. As you said, you now don't need reading glasses.
Cornea-based refractive surgery like Lasik, All-Laser Lasik, PRK, LASEK, and Epi-Lasik do not resolve the cataract development issue. If this is a part of your vision change and you do not yet have mature cataracts, then you may want to consider
Refractive Lens Exchange (RLE).RLE is exactly the same as cataract surgery and may resolve both early stage cataract development and your refractive error problem.
Of course, if you fully correct your refractive error you will be back to wearing reading glasses. You may want to investigate
monovision correction as a possible alternative. You can have monovision with contact lenses, cornea-based refractive surgery, or RLE.
If you actually have cataracts, then the cost of surgery would be covered by your medical insurance including Medicare. RLE is considered elective and would not be covered by most insurance plans, including Medicare.
Dry eyes will contribute to poor vision quality no matter what the refractive error. You may want to read our article regarding
dry eye treatment for ideas that may be helpful.