Monofocal iol set to plano

thank you very much indeed! My grandad has two near monofocal, he need glasses for watching tv but he goes around in the house without wearing them. how is that possible? the bluriness is not that strong? I'm myopic, so used to see dreadfully far away, already from 50-60 cm and beyond. I have also keratoconus and irregular astigmatism.

I think that that unless one is trying to read something or is interested in some detail, it is hard to know how good or bad the vision is. Thus, your granddad knows that he needs to wear glasses to see the TV well. So, he uses the glasses. Even though his intermediate vision is probably not good to read at 100 cm, for example, he can still move around fine even if the vision is not good at that distance.

As an example. before my cataract surgery, when wearing my contact lenses with one eye set for far distance and the other one set for reading, my intermediate vision was fine for day-to-day activities and I never wore glasses. The only time I missed having good vision at the intermediate distances was at some unusual situations, such as trying to read captions from about 70 to 100 cm away next to paintings in a museum. So, it all depends on your life style as to how good a vision you need to have at the intermediate distances.

My suggestion will be for you to either have the combination of far / intermediate or intermediate / near focus for the 2 eyes, depending on whether you would prefer to use glasses for reading or for driving / watching TV.

Thank you! Tell me something please that I really don't understand: what is the difference between wearing glasses for far away when you are myopic and still have your own natural lens and wearing distance glasses when you have monofocal for near vision?

The difference is not that much. The exact difference depends on how much natural focus adjustment is still left in your natural lens (even if you are myopic). The older a person is, the lesser the natural adjustment tends to be. The monofocal lens, which you will have after cataract surgery, will have no focus adjustment. Thus, there will be some loss of range in the distance over which you will be able to see clearly.

I have two more questions please:

1) How is the level of bluriness for the not corrected distance by monofocal iols?

2) If I have implanted monofocal for close, wearing glasses for distance, lets me to see close even with glasses on? Or I must put them down?

If you get both monofocal lenses for reading distance of about 40 cm, your uncorrected far distance vision will be rather blurry: probably about 6/30 in the metric system.

Also, in that case, if you were wearing glasses to see at a distance, you will have to put them down to read unless the glasses were bifocal, trifocal, or varifocal.

I really think that most people can adjust to small differences in the prescription power for the 2 eyes (i.e.micro-monovision). So, you should seriously consider one of the following 2 options:

1. Have one eye set for far distance and the other eye set for the best focus at about 100 cm. This will correspond to requring a prescription of 0D and -1.0 D for far distance for the eyes. The 2 eyes together will then be able to see well from about 65 cm to far distance. One will still need reading glasses.

2. Have one eye set for reading at 40 cm and the other eye set for the best focus at about 67 cm. This will correspond to requring a prescription of -2.5D and -1.5D for far distance for the eyes. The 2 eyes together will then be able to see well from about 35 cm to 100 cm. One will need glasses for distance (the uncorrected distance vision will be about 6/20 in the metric system).

What prescription would you suggest for piano playing/reading musical score?

That will depend on the distance range, which you feel that you will have to have to be able to read music while playing piano. If you can share that, then I may have a corresponding suggestion.

Like this, distance from keyboard and from score:

http://www.globalgiants.com/archives/fotos19/SteinPiano-01.jpg

Seems like a distance of about 50 cm, which corresponds to a prescription of about -2.0 D.

If you want to be able to do that without glasses, you can set both eyes to the best focus at that (or close to that) distance. However, my suggestion will be the option 2 above; viz, "Have one eye set for reading at 40 cm and the other eye set for the best focus at about 67 cm. This will correspond to requring a prescription of -2.5D and -1.5D for far distance for the eyes.The 2 eyes together will then be able to see well from about 35 cm to 100 cm."

I heard many people have troubles with monivision, with one eye far and the other near. Is that mini-monovision more natural? 

I have one more question please: I have irregular astigmatism: is toric iol a good solution? I don't want to have aberrations, halos, glare and so on with a toric lens. How is about that?

The the mini-monovision which I am suggesting requires a difference of only 1D between the 2 eyes. That is very easy to adjust to.

A Toric IOL can take care of regular astigmatism, but not irregular astigmatism. Thus, that will be of no benefit to you.

If the irregular astigmatism is really bad, one can have LASIK enhancement done after the cataract surgery, but if you have been living with it all these years, that is probably not that bad.

Thank you very much, at201! Are you a doctor? You look very expert about those things Putting a toric iol with irregular astigmatism may not help at all about astigmatism or could even aggrave the situation with halos and other aberrations? 

I am not a medical doctor. Am just interested in being knowledgable in the areas which affect or have affected me.

Having an irregular astigmatism, does make the measurment of iol power problematic?

 

Usually, having a small amount of irregular astigmatism should not make it any harder to measure the IOL power. However, if your eyes are keratoconus, then depending on how bad it is, there is a potential for it making it harder for the doctor to determine the best power.

As a side note, the determination of the IOL power can be off by about 0.5D even for people with no irregular astigmatism. So, it is good to have one eye done first and wait for 2-3 weeks for its vision to stabilize before selecting the best power for the second eye. This will be even more important in your case.