Cataract Blindness

[anitajay]

Can untreated cataracts lead to permanent blindness or can cataracts always be treated even if it does lead to one being blind in the eye?

[JohnHaganMD]

Cataract caused poor vision or blindness is called "reversible" blindness because if the cataract is successfully removed and the other parts of the eye and brain are in good or reasonable shape vision can be restored. Glaucoma and optic nerve disease can cause "irreversible" blindness    Cataracts are the #1 cause of reversible blindness in the world

[anitajay]

Thank you Dr. Hagan. I also had another question regarding AION. I often notice blurry vision in one eye when waking up from lack of sleep. Its in the eye with worse cataracts and I also have dry eyes. Is it a possibility that it could be AION? Or is it more commonly related to dry eyes?

[JohnHaganMD]

AION = anterior ischemic optic neuropathy. Two types "arteritic" related to temporal arteritis (Giant cell arteritis) rare, and uncommon in young and middle age people. Other is "non-arteritic" much more common. Never related to dry eyes or eye problems. Related to hypertension, diabetes, nicotine use, obesity, poor health habits. Your symptom of blurred vision on awakening would never be related to AION which is blurry all the time.

[anitajay]

Dr. Hagan, can untreated cataracts lead to irreversible damage of the retina? How do patients know when "too long is too long" in waiting to get surgery?

[JohnHaganMD]

The only mechanism that I can think of is if a cataract becomes "too ripe" or what Eye MDs call "hypermature" it can raise the pressure in the eye and cause severe inflammation. The inflammation and pressure could blind an eye. This is ultra rare in developed countries and has become much rarer in developing countries that several generations ago.

[SoftwareDeveloper]

Since someone is asking about the impact of untreated cataracts, perhaps its useful to note that I gather if you wait too long  the cataract becomes  mature and hard. I gather that rarely happens in developed countries since the vision would be rather bad by then (certainly before the person was blind), except in cases of atypically rapidly developing cataracts.

A mature hard cataract   makes it more difficult to break up and remove the lens, and especially with certain types of cataracts can increase the odds the capsular bag might be damaged during removal. If the capsular bag is damaged, the IOL may need to be placed outside the bag, which is slightly more complicated even if the results are still usually good (and most if not all  premium IOLs can't be used outside the bag, not that its usually likely to be an issue for someone who has waited that long for treatment).

[SoftwareDeveloper]

[2nd comment due to comment system bug, it was suggested if a post doesn't show then posting again may get it to]

[JohnHaganMD]

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[anitajay]

SoftwareDeveloper,

So in most cases results will only be good but not "optimal" if the capsular bag is damaged? Also if it needs to be placed outside the bag does that mean the patient won't have an option to go for premium IOLs if having waited too long?

[SoftwareDeveloper]

As this article (and similar ones) that talks about 1 piece vs. 3 piece IOLs notes, a   1 piece IOL requires an intact capsular bag:

http://epubs.democratprinting.com/article/CATARACT_SURGERY%3A_Optimizing_IOL_Selection%3A_One-Piece_vs_Three-piece/680057/64262/article.html
"One-piece lenses, by contrast, require an intact capsular bag, or at least an intact capsular fornix (small posterior capsular rents may still be compatible if the one-piece lens can be stabilized within the bag). The onepiece IOL should never be placed in the sulcus, since such placement is often associated with chronic inflammation and pigment dispersion—the latter problem most likely stemming from the large, truncated one-piece haptics rubbing against the iris."


Most premium IOLs (including all the common ones people talk about like Symfony, Crystalens, trifocals, the common Tecnis&Restor low add bifocals, etc) are 1 piece IOLs. I'd seen mention of 3 piece bifocals, though I don't know for sure if they are still around.

As to the risk that the capsular bag will be damaged removing a very mature cataract (preventing a 1 piece IOL from being used)  or what the rate of complications is for a very mature cataract or the quality of results, I don't know for sure and I'm not curious enough to research exact statistics or details. I don't know if the doctor might have any comments.

[JohnHaganMD]

With modern cataract surgery done by an experienced ophthalmologist surgical compliations only occure about 1-2% of the time. Most of these do not lead to a bad result. The most common complications are "capsular bag tears" and "vitreous loss". Without getting too complicated they are all very unique and different. Sometimes you can proceed with the same IOL as planned, at other times have to forego "Premium" IOLs and worst case no IOL at all. Don't get hung up on the worst things that could happen, you don't do that when you get in your car to drive.

[SoftwareDeveloper]

The concern I had was people postponing cataract surgery to the point where it has at least some small impact on the results, if they think "even if I were blind they could still fix it". For the most part I gather it isn't a big deal postponing surgery until you decide the visual problems are bad enough it is worth doing since the risks don't change much during the early phases of a cataract. However  at some point a cataract does become mature enough to increase the risks, so I figure its important for people to be aware of that.

Obviously they should also be aware that the results are likely still to be good and its worth the risk of doing it even if they have waited until the cataract is mature.

[JohnHaganMD]

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