I'm 54 years old. Bilateral radial kerototomy in 1992. Cateract surgery, lens implant in right eye in year 2004. My vison was pretty good after surgery but since has degraded to 20/40. No YAG needed. I'm simply getting my astigmatism back. My question is: Is replacement of an IOL risky surgery? If so why.

Replacement of an IOL is not without risk. The question is: If your vision was good after surgery, then what has changed? If your cornea is unstable (and it sounds like it is), what advantage will IOL exchange provide? There are astigmatic IOLs, but if the cornea is not stable, implanting one will not guarantee sustained good vision. Also, post-RK astigmatism is often irregular astigmatism. A toric IOL cannot fix irregular astigmatism.

Removal (or exchange) of an IOL is best performed within the first few weeks after surgery. Four years later is a long time. Usually the posterior capsule contracts around the IOL, increasing the risk of retinal detachment if removal is attempted.

I should also mention that in 1991, my pre RK prescription was -3.50 with significant astigmatism. Will my corneas ever become stable? If IOL replacement is not advised at this time what are my surgical options? Do you think Laser surface ablation is an option? http://www.osnsupersite.com/view.asp?rID=24804

http___www.osnsupersite.com_view.asp_rID_24804.pdf (198 KB, 15 downloads) Laser surface ablation

"After surface ablation with MMC, mean uncorrected visual acuity improved from 0.66 D ± 0.43 D to 0.4 D ± 0.15 D (P = .0001). Best corrected visual acuity improved by two lines in seven eyes (35%) and remained unchanged in 10 eyes (50%). No patients had BCVA worse than 0.18 D, and 95.5% of patients had corrected vision within 1 D of the target refraction."

Best corrected acuity "remained unchanged in ... 50%" and, if you do the math, was worse in 15%. That doesn't sound like great success. You have to be careful when reading some of these reports. The titles often put a very positive spin on the actual outcomes.

When you say your vision has degraded to 20/40... is that spectacle-corrected acuity or uncorrected acuity?

Thank you for the replies, I'm learning a lot. As an RK patient I'm always looking for something to improve my vision. 20/40 uncorrected vision. Is an RPG contact lens the only option for RK patients?

What is your best corrected (spectacle) acuity?

My best corrected (spectacle) acuity is 20/25

From my perspective, good spectacle corrected vision always trumps poorer uncorrected vision. Sometimes chasing down better uncorrected acuity is just not worth the risk. What if, in an attempt to reduce your residual refractive error, your uncorrected acuity improved to 20/30 but the CORRECTED acuity was reduced to the same 20/30. Would that be a reasonable trade off? I don't think so. As they say, better can be the enemy of good.

Nearsightedness and farsightedness are not derived from improperly curved corneas. Altering the natural cornea to correct nearsightedness or farsightedness, although effective, is a trade off in visual quality. Why and how some RS patients lose too much quality, to the point that they regret their decision, has not been researched enough to be able to screen out patients destined for similar problems.

One thing I hear all the time from patients is, "When will the surgery be perfected?" The only logical answer is to acknowledge that the natural cornea is mostly perfect to begin with.

Dr. Hartzok's remarks posted on May 7, 2008 are absolutely on target. His final sentence states exactly why we have risks when we alter our corneas for procedures which will likely not achieve the same best corrected visual acuity without annoying and occasionally lifelong undesirable outcomes from a totally elective surgery.

I truly appreciate Dr. Hartzok's commentts and totally understand. Based on the information I provided in my post, do you think I would be a good candidate for RPG contact lens? I have 8 cuts for myopia and 4 cuts for astigmatism. Are you familiar with corneal collagen crossling to help strengthen the cornea? http://www.usaeyes.org/lasik/faq/c3r-crosslinking.htm
It might be an effective treatment for radial ketetotomy patients.

Corneal_Collagen_Crosslinking.pdf (125 KB, 20 downloads) Corneal Collagen Crosslinking

If you replace your IOL (which I neither recommend nor advise against), you might want to consider a Calhoun Vision light-adjustable lens (LAL), which is a lens where the prescription is programmed in after the implantation. These lenses in principle have the potential to treat irregular astigmatism...it has to date at least been effective in treating regular astigmatism with very good accuracy. Dr. Guell recently presented about using LAL to deal with post-LASIK cataract patients, and it rather successfully avoided the 'refractive surprise' problem. He's fairly optimistic about treating irregular astigmatism soon, and your timing would be good I think.

Being younger, I'm very curious about phakic versions of this lens, but these are a couple of years away...