predictive power of retinal exam?

I have high myopia (-7.75/-5.75) and I understand that this sharply increases my risk of retinal detachment at some point, and that a cataract operation increases the risk further.

So my surgeon has referred me to a retina specialist for an examination. That appointment is next week, but I am curious about the following.  If my risk of detachment after surgery is 7% or so, is that for a population that did not have a retinal exam before surgery? If one studies only those who have had such an exam and been given a clean bill of health prior to cataract surgery, is the incidence of detachment after surgery lower for that population and by how much? (If this is not known, what is the point of going to the specialist?)

My need for surgery is not really critical: I can't read highway signs at a distance, and I have to get close to see airport flight displays and Powerpoint presentations, and text on the tv is fuzzy, but I can still drive and read and watch tv. So what I have to decide is, even if my retina looks perfectly healthy, should I wait until I'm closer to being visually incapacitated?

Many thanks for reading this longwinded explanation.

  

[Michael J Kutryb, MD]

To me, you are not that nearsighted.  I think it's great that you are getting a retinal exam by specialist, however.  If that looks ok then I personally would not be that worried about the risk of retinal detachment.  I'm not trying to downplay the risk but someday you will need cataract surgery and you will have a somewhat increased risk of RD but that shouldn't stop you from having surgery.  Just a  rough guess in my mind  puts your risk around 1/250 to 1/500 but that may be different than your reading.  Rememer, ANYONE can get an RD after cataract surgery but it is fairly rare.  In over 6000 cases I've seen about 5 detachments that occured mostly 6-12 month after surgery and many of those people could have gotten a detachment anyway even if no surgery.  Talk to your surgeon - I think the risk may be less than you believe.  I appreciate your thoughtful approach to having the surgery - there are always risks/benefits to most things and I think much the same way you do.  My guess is that you have about a 98 -99% chance of good outcome.  But I don't know all your specifics and am not your doctor so take the advice of your doctor, not me.

MJK MD

[Chuckles960]

Many thanks for your encouragement! However, what I am trying to do is sort out confusing information. I posted a related question (by mistake) in two of your forums and got very different replies, one from you and one from Dr. Hagan:

http://www.medhelp.org/posts/show/368899

http://www.medhelp.org/posts/show/368678

Looking at the web (and even some original papers, including an old paper referred to in Wikipedia that found a risk of 7%), I am still confused about how much risk I am actually taking.  1 in 400 is one thing and 7% is another thing entirely!  It would be nice if there were a controlled study of myopic people with healthy retinas (pre-op) who then have cataract surgery. I assume hard numbers for this do not exist?

Thanks again,

[Chuckles960]

Here is the reference: S.W. Hyams, M. Bialik, E. Neuumann, Br. J. Opthalmol.59, 480 (1975)

http://www.ncbi.nlm.nih.gov/sites/entrez?cmd=Retrieve&db=pubmed&dopt=AbstractPlus&list_uids=1203233

Abstract:
Retinal detachment after cataract extraction occurred in nine out of 136 eyes with myopia of 6 or more dioptress (6-7 per cent), during a follow-up period of 1 1/2-9 1/2 years. Five of the nine detachments occurred within 3 months of cataract extraction. All patients with retinal detachment were under the age of 63 years. Relatively young patients with high myopia bear a special risk of developing retinal detachment after lens extraction. The possible reason for this is discussed.

[Michael J Kutryb, MD]

Just FYI, in 1975 doctors routinely used 11 mm incisions and 9 or more sutures with extracapsular techique and some were still doing intracapsular techniques with no implants or anterior chamber implants.  TOTALLY different era in cataract surgery so you cannot compare to current techniques.  MUCH more stressful on eye.

Regarding your eyes.  If you need cataract surgery - what else are you going to do?  My advice is to have retina thoroughly evaluated and find the best cataract surgeon available then go forward with your cataract surgery - when clinically indicated.  The high probability is that you will not have a detachment - and since your retina has been so well looked at by specialist, that should give you some peace of mind.  

MJK MD

[kg17]

Just related question, does risk of cataract surgery ever level out?  Meaning, if I have cataract surgery at age 37 with extremely myopic eyes, do I bear a continued additive risk (on top of risk due to long eye) for every additional year after the surgery?  I'm trying to understand how my "young age" increases my risk for retinal detachment as I age after cataract surgery.