Why didn’t my toric lens fully correct my astigmatism?
MAY 06, 2022
Question:
I had a toric Symfony lens implanted in both eyes. In one eye I still have the same astigmatism I had before the implant. The surgeon is recommending a limbal relaxing incision surgery. I am having a lot of night aberrations. He thinks this could help. Is it possible for LRI to help the night issues and is this the best approach to correct the astigmatism? I'm confused why the toric lens did not correct the astigmatism in the first place.
Answer:
A toric lens implant is an excellent way to correct limited amounts of the most common type of astigmatism (an irregularly shaped cornea that distorts vision) in a patient who is going to have cataract surgery. The implant lens must be positioned exactly for your astigmatism. One of the problems with any toric lens is that they might shift position in the early days after surgery, reducing the desired effect. Sometimes the cataract incision changes the astigmatism from the preoperative measurements, thus changing the effect of the toric lens you are given.
LRIs (limbal relaxing incisions, incisions made between the cornea and white of the eye to correct astigmatism) were used before toric implants were perfected and are another method of treating astigmatism. LRIs can be used without entering the inside of the eye, but work best for fairly small amounts of astigmatism. LRIs don't rotate like toric lenses can do.
Sometimes we use both torics and LRIs when the astigmatism is greater than the toric can correct.
If you want to avoid glasses or contact lenses, the solution your eye surgeon advises is your only option without going inside your eye again. When weighing the risks and benefits, it is recommended that the surgeon not go inside the eye again and instead have the LRI.
If aberrations such as halo and glare are the major issues, correction of the astigmatism may not take care of this. Some patients with multifocal or extended depth- of-focus lenses do not adapt to the optics of the lens. If this is the case, removal and replacement of the lens with a traditional monofocal lens may be the best solution. If the amount of your residual astigmatism is low, this may be the best solution for you. Please discuss with your surgeon.
This question was originally answered on October 3, 2017.