1)The incision from the surgery could have caused you to develop additional astigmatism as it healed. The Toric lens can only address what they previously measured, it cannot help with what was surgically induced as it wasn't there when they determined your IOL power
2) The toric lens could have rotated a little bit as it healed, inducing astigmatism
3)Either the toric lens or scarring from the incision or a combination of both factors could be inducing something calling "irregular astigmatism" which is not correctable by glasses. An RGP contact lens may help. Some doctors have specialized equiptment that allows them to test for the existance of irregular astigmatism.
4)I have read reports of toric IOL implants rarely resulting in cases where vision is no longer correctable to 20/20 and nobody was really certain why this happened. In the case I read explantation and replacement with a regular monofocal resolved the issue. This is by no means common but I have read a case study about it. Patients best corrected went from 20/20 to 20/40 with no discernable reasons until the toric IOLS were explanted. I do recall that she had large amounts of corneal astigmatism and had worn RGP contacts all of her life to correct it, but after surgery even the RGPs did not help with the toric IOLs.
5) An IOL is not your eye. It's prosthetic. Quality of vision typically suffers somewhat and for some may noticeably not be as crisp as it was before.
Hi Curly! I don't know much about the astigmatism part of your question, but concerning the possibility of worse distance vision, maybe it has something to do with dry eyes?
Even simple cataract surgery, with small incisions, cuts some of the corneal nerves. This can evidently cause temporary dry eye until these nerves regenerate. My understanding is it may take a few months until they regenerate.
If you have any feelings of dry scratchy eyes, and/or artificial tears seems to improve your distance vision, maybe you should give it a little more time. I know my eyes still seem to get more dry after my surgery, than they did before, and that was almost a year ago. I also notice better vision at certain times of the day, or just after waking in the morning versus later in the day.
Thank you BOTH for your responses (Hi Nancy!). I sincerely appreciate it. It was a little disheartening reading it to some degree but I suppose I will remind myself constantly that my RE does see better than before. I do just wish that people weren't led to believe that they'd see so well afterward. I just hope it's a LONG time until my LE needs the cataract removed because it still sees so well and has truly 'carried' me.
Nancy, I will give it more time like you suggested and I may reread some of our old posts (in our other conversation) to see what you said about getting a prescription and dry eyes. I am using Systane Ultra and like it a lot.
Do you think that my eye could still be fluctuating enough that my optometrist got a wrong reading? I may ask him to check it if he's willing. I do remember that day it was difficult for me choosing the #1 and #2 on the optical machine (like I mentioned). I was blinking like crazy trying to see.
There are many factors which can affect the accuracy of an attempted correction with toric IOLs, of which 1) and 2) are important ones. Also, pre-op measurements of corneal power may have variations/inaccuracies depending on whether the posterior corneal curvature is taken into account.
RGPs may help with irregular astigmatism, but unfortunately when a toric lens has been implanted, it will 'unmask' the toricity of the IOL. Since the toric IOL is meant to cancel out (regular) corneal astigmatism, and the RGP also does the same thing, so the double correction causes the astigmatic effect of the IOL to stand out. If an RGP is worn, in other words, glasses would need to be worn on top to cancel out the toricity of the IOL.
When we refract patients, there is a technique of checking cylinder using what is called a Jackson cross cylinder. The end point (ideal point) of this test is when #1 and #2 look the same, ie if they are equally clear/blur. That could be one reason why it was difficult at the end to say whether #1 or #2 was clearer-they were meant to look the same.
However, the crux of the matter is that at the end of the day, vision in the affected eye was not so good. There are a number of potential reasons, which a full eye examination should reveal. If assuming that the eye exam with the MD is completely fine, one possibility is to re-refract the eye ie to get a second refraction measurement...