Q:  I am very nearsighted and I have astigmatism. I'm 25. My vision is: o.d. -13.75 -0.50 55 o.s. -12.00 DS What kind of results could I expect with Lasik? A: You are at the very upper end of what is treatable with Lasik, and many doctors would say that a person with your prescripton should not attempt to achieve a full correction. In such a case, only a partial correction would be possible, which would make you much better but still leave you with thin glasses or contact lenses. Another possibility is the phakic implants, commonly called intraocular contact lenses. Andrew Caster, MD

Q: My daughter wants the laser eye surgery and she is only 13. Is it possible to sign an agreement stating that she is allowed to get it done? A: It would not be wise to perform the surgery on a 13 year old. The odds are very high that her eyes will significantly change over the next few years, so it is best to wait until her eyes have stopped changing. Andrew Caster, MD

Q: How many enhancements can be done? Can overcorrection be corrected? A: Overcorrections can be corrected. It is possible in most cases to perform several enhancements, if needed. It will depend on the thickness of the cornea. Andrew Caster, MD

Q: Just out of curiosity. If someone was to receive LASIK, would it be detectable during any of the standard eye examinations (months after surgery)? A: It is possible that the edge of the flap could be seen months later, though often it is very, very difficult to see. A topography test will usually show that the procedure was performed. Andrew Caster, MD

Q: I just had lasik done 3 days ago. My prescription was very high with astigmatism. They said I don't have enough cornea to do a touch up surgery. In time, can the cornea heal enough to do a touch up? A: Often, when a touchup is not advisable with Lasik, a touchup can be done using the PRK laser technique. Andrew Caster, MD

Q:  My prescription is =10.25 -1.50x040 and -11.25 -2.00x165. (My corneas are in the normal range, but on the thin side of normal...although I don't know the exact size) I have sought two opinions for LASIK -- but received conflicting advice. One surgeon advised that he would only do PRK because of the amount of correction required; a second surgeon said that I'm not a candidate for PRK but am a borderline candidate for LASIK (although not wave-front). Can you explain why I would get such opposite advice? A: Your correction is at the higher range for laser vision correction. One doctor may have felt that your corneas were too thin for lasik. Some doctors do not like to perform PRK for higher corrections, whereas others feel comfortable. Andrew Caster, MD www.CasterVision.com

Q:  I had an eye injury when I was 4 years old; the corner of a 3/4" sheet of steel entered my eye. I now have scar tissue on my retna, a slightly deformed iris (due to entry), and 20/80 vision in that eye (right). In four years, I will be entering a career in which my eye sight may not be worst than 20/60 and must be able to be corrected to 20/20. Is there any way I can use these four years to my advantage? Do you have any advise on how I may correct my vision to suit my chosen career? A: You need to be evaluated in person by a lasik specialist. Andrew Caster, MD www.CasterVision.com

Q: I had PRK surgery on my left eye 11 days ago. My vision is still a bit foggy. Is this normal? A: PRK takes longer to heal than Lasik, and it is expected that the vision would be a bit foggy 11 days after the procedure. Andrew Caster, MD www.CasterVision.com

Q:  Dear Dr Caster, I do not currently have my glasses prescription but I do have my contact lense one and it says: left eye BC 8.7 power -4.75 cyl -2.25 axis 110, right eye BC 8.7 power -5.25 cyl -2.25 axis 050. However when I am wearing them, or glasses, I am only able to see the first 6 lines in the wall charts at the optician's (in the UK). I will be 18 in march and was looking for an impartial opinion on how effective lasik would be for me (How well would I be able to see after the treatment) and how old I would need to be before being able to undertake the treatment. A: Your prescription is good for laser vision correction, but the other measurements of the eye must be within the proper bounds. People in their teenage years sometimes are still growing and their prescriptions can still sometimes be changing, so you should wait until you have two years with a total of less than a 0.5 diopter change (that would be in the first two numbers for each eye). Andrew Caster, MD

Q:  Hi, I am 42 and have had myopia pretty much all my life. My prescription is -7.0 and -7.5 and has been steady for the last 20 or so years. I also have astigmatism in one (or both eyes) and I currently wear glasses. I had an eye examination in New Zealand last June and was told my cornea flaps (?) were thick enough, that I was eligible for laser Lasik but that I wouldn't achieve 20/20. There was a slight problem the doctor said, I can't remember the name she gave it but she demonstrated the problem by holding up a pair of black 'glasses' made of paper which had tiny tiny holes in them shaped like a cross. With these I could see the letters on the board much better. Please could you explain the 'problem' to me and how it would affect the results of Lasik surgery. And if, indeed, you think Lasik is for me. Thank you Very Much Ellie W. A: I need more information than what you have provided. I would recommend that you see another doctor to get a second opinion. Andrew Caster, MD