Tortic IOL

[uxuh]

My left eye need cataract surgery, I went to see two Eye MDs. One doctor recommends using Alcon Toric lens Model # SN6AT4 and the other recommends SN6AT5.
Cylinder power options for above IOL:
                                              SN6AT4                 SN6AT5
Cylinder Power
  IOL Plane                              2.25D                    3.00D
  Corneal Plane                        1.55D                    2.06D
Recommended
Corneal Astigmatism                1.5 -2.00 D            2.00 D and up
Correction Range

When I was in their office, they were using serveral tools to measure the K value of Astigmatism, the range is aroung2.1 to 2.3 and one doctor uses the Toric lens calculator to get the axis of implant which is 83 degree.

Why there is a difference in choosing the IOL? What is the right question to ask?
None of doctors mentioned the IOL spherical power selection. From the last eye glasses prescription when left eye was good (-1.50,  -1.75x159). What is the choice of IOL spherical power for my left eye? From Alcon solf IQ calculator for Toric IOL the selection range of spherical power is 6D to34 D, Is there any correlation between eye glasses near sight prescription number and IOL spherical power number? If there is what is the correlation? Is there any correlation between the eye glasses axis for astigmatism prescription and Toric IOL implant axis? If there is the correlation what is the correlation.

[John C Hagan III, MD, FACS, FAAO]

There are many (scores) of IOLs that will fit your eyes, just like there are hundreds of thousands of shoes that would fit you feet.

There is no correct answer. "different strokes for different folks"  Spend some time using the search and archives to read the extended discussions of the matters you are pondering

JCH MD

[JodieJ]

I believe that over correction of astigmatism can result in irregular astigmatism (not a good thing).  I'd go for under correction.

As a former cataract surgery patient, I think you might be too concerned about making the surgeon feel uncomfortable.  You have a right and (in my opinion) a responsibility to contribute to the process of selecting the refractive target for your IOL.  (It's YOUR vision, after all.)  I think you should set up another appointment with each surgeon to discuss your goals for your post-surgery vision (e.g., excellent distance vision, mini-monovision, etc.) and to obtain their recommendations.  Personally, I wouldn't consider returning to the office of a surgeon who was too busy to meet with me about this.    

[uxuh]

Thank you very much for answering my question.

What should I do now? Two surgeons are all Kaiser's member. They know what I am doing. I do not know if I keep going back and challenging their decisions would make them uncomfortable. Choosing IOL has a fundamental problem- can not try on first. May be my best bet is to choose the IOL close to my last eye prescription. What do you think?

Assuming only one IOL model is best fit my eye. If I am implanted an inferior one unluckily, which one is easier to correct by eye glasses? Under power or over power? I remember you were saying "some astigmatism would help focus "persudoofocus?"" Does it mean under power is easier to correct?

[John C Hagan III, MD, FACS, FAAO]

The calculations are complex, there are multiple forumulas, often there is a individual A constant based of the surgeons results using regression analysis.  Other variables include radius of curviture of cornea, depth of anterior chamber, length of the eye.

So your questions cannot be answered without multiple other variables. You should ask these of the surgeons you are considering

JCH MD