Dr. Desmond Fonn is a well-recognized and respected figure within the contact lens industry. The University of Waterloo bestowed the honor of “Distinguished Professor Emeritus” to Dr. Fonn in June 2012 in recognition of his research and work to the university and academic community.

At CooperVision, we are thrilled to share an article that Dr. Fonn has provided to us exclusively. The subject is on astigmatism and toric soft contacts. (You can read Dr. Fonn’s article here on our blog that’s geared to eye care professionals.)

Since Dr. Fonn’s article is written for eye doctors, we wanted to provide you with its findings in a manner that the rest of us would find more digestible to the layperson. After all, the information contained within it is extremely interesting.

Essentially, Dr. Fonn says that if you have refractive astigmatism, and you would rather wear contact lenses instead of glasses, eye doctors should fit you with toric soft lenses. (By “fit” here, we mean the process of an eye doctor examining your eyes and finding the right lenses for your prescription.)

So let’s break this statement down:
“Refractive astigmatism” refers to the refractive visual blurriness you get from a cornea or lens that’s stretched into an irregular shape (think: more like a football instead of a basketball).

This causes a refractive error, or a distorting of light as it enters your eyes. Because of this, nearly everything you see—near or far—may appear slightly blurry depending upon how much distortion you’re experiencing.

Dr. Fonn goes on to say that soft lenses provide superior comfort, which is naturally what everyone wants. This makes sense. So where is the problem?

Toric contact lenses must be “fitted,” in industry parlance, so that they are oriented the right way to correct your individual vision needs. This is often done by providing “thin thick” zones in the lens, so that the bottom is heavier than the top. This helps gravity pull the thicker part of the lens down for the correct orientation.

In his summary, Dr. Fonn says, “As the average thickness of toric lenses is influenced by the by prism ballast or periballast and therefore increased thickness in parts of the lens, the oxygen transmissibility may be compromised and this will almost always be negated by the use of silicone hydrogel materials.”

Here, he’s referencing the lens stabilizing we just covered. This increased thickness in the lens could affect the ease at which oxygen can pass through the lenses. This is important because your corneas get their oxygen straight from the air around us. Unlike our other body tissues, the cornea contains no blood vessels to deliver needed oxygen.

However, silicone hydrogel lenses can help provide excellent oxygen transmissibility. (This is measured in their “Dk” value, often written as “Dk/t,” if your eye doctor should mention it to you.) Since silicone hydrogel lenses tend to offer a higher rate of oxygen transmission (there’s our “Dk/t” number) than standard hydrogel contacts, this would negate the increased thickness at the bottom of the soft toric lenses.

Simply put, you would have your “contact lens comfort” cake and eat it, too—and that’s always a good thing.

We invite you to read the entire article by Dr. Fonn here. If you have any questions or would like to comment, please feel free to do so below!


Nothing in this article is to be construed as medical advice, nor is it intended to replace the recommendations of a medical professional. For specific questions, please see your eye care practitioner.


[1] Dr. Desmond Fonn receives the honour of Distinguished Professor Emeritus
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Avaira contact lenses

Avaira family

Two-week replacement schedule, Soft and flexible for a variety of needs, Silicone hydrogel material + UV blocking*, Naturally wettable so you're less likely to need additional wetting drops
Biofinity contact lenses

Biofinity family

Monthly replacement schedule, Lenses stay moist and comfortable, Naturally wettable so you're less likely to need additional wetting drops

clariti 1 day family

Convenient daily replacement schedule, The healthy advantages of silicone hydrogel lenses, Vision correction for nearsightedness, farsightedness, astigmatism and presbyopia, Supports excellent all-day comfort, UVA and UVB protection*
Proclear contact lenses

Proclear Family

Convenient daily disposable contact lenses, Superior aspheric optic design for optimal visual sharpness, Maintain 96% hydration - even after 12 hours of wear, Designed to address discomfort from eyes


I am reading alot of complaints that your toric lenses are tearing easily, sometimes while in the eye. For the price if a lens tears in one or two days and is supposed to last a month and so many people are having this problem there seems to be a problem with your product. This disappoints me because all the reviews I've read say your product is the most comfortable toric lens but the least durable which makes the already pricey XR version more expensive and not a financially feasiable option. Is your company aware of this issue and if so is something being done to correct it? With so many people having premature tearing I don't think you can say it is a handling problem as some of these people are 20+ year contact wearers who have plenty experience with proper handling of contacts and you have to admit there is a problem here. Does your company replace prematurely tearing lenses? I have read reviews where someone had two different prescriptions for each eye and one entire box for one eye teared prematurely and the other box didn't. That is clear evidence there is a problem with the product. Please email me with a response as I really would like to try your product. My email address is jasoncollins1201975@gmail.com.

I recently got back into contacts after taking a few years off from wearing them, and I am having an issue with this brand of lenses prematurely tearing.

The box for my left lens (each of my eyes has a different prescription) seems to be faulty, as three left lenses have torn in three weeks. I haven't experienced any problems in the box for my right eye (yet). I am very careful in handling the lenses, and they have been tearing when I simply blink, even when using re-wetting drops for contacts.

For an expensive prescription, I am thus far extremely dissatisfied with this brand and will not be staying with it if the lenses keep tearing for no apparent reason, as I can't afford to keep paying high prices for monthly lenses that are only lasting a week.

Very disappointing.

Hi SJTetzlaff: Thank you for reaching out to us. We have sent your feedback to our consumer care group.  If you have any further questions, please contact us at CC@CVLens.com. We kindly ask that you retain your lenses so that we can inspect them if necessary.

Hi Jason:
Thank you for your feedback. We have sent it along to our team and if you have any further questions, please contact our consumer care group at CC@CVLens.com

Also having issues with your proclear contacts ripping after a few days. the longest i have had a pair last was a week and a half. i have worn contacts for about 5 years so im being gentle. i just bought 2 boxes for about $240.00. and im worried they are all going to rip.

Hi Blaine Cousins: Thank you for reaching out to us. Your feedback has been sent to our consumer care group. Please email your contact info at CC@CVLens.com  so we can learn more about the issue.

Hello, I would like to corroborate Jason's testimonial. I have been trying to wear Proclear XR lenses for over a year now. For the first year, I did not really experience any tearing, but in the past month or, all of a sudden the tearing is incredibly frequent. In the last month alone, I believe I have had 4 pairs tear. One of those 4 times, a lens tore while still on my eye, and it was incredibly difficult to remove. Proclear XR lenses are indeed the most comfortable I have ever worn, but unfortunately they have become far too fragile. The lenses are also incredibly expensive compared to other brands of lenses, and so it just doesn't seem to be worth it. I hope you manage a way to make the lenses more durable.

Hi RP: Thanks for reaching out to us. We have sent your feedback along to our team and if you have any further questions, please contact our consumer care group at CC@CVLens.com. We kindly ask that you retain your lenses so that we can inspect them if necessary.

I have a tearing problem with CooperVision Pro Clear XR Toric lenses. I go through a box in less than a month. (They are supposed to last a mont a piece not a day.) The last 2 lenses tore the first day. One was still in my eye. I have dry eyes and a +7 prescription. I have cut off my finger nails. Have you a solution? PLEASE!

I have had the same issue and when i contacted CooperVision they told me to go back to my eye doctor. They provided me with a case # and now my eye doctor won't get back to me. Cooper vision, my case # is CC242932. These contacts are too expensive to keep ordering.

Hi TJ: Thank you for contacting us.  Our Consumer Care group will look into this and contact you directly with any updates.  

I have been wearing toric lenses for 10 years and I just got these and three lenses tore in a 2 week period. I will contact the email you have provided for others as well as my own eye doc but I wanted to post here because there is obviously a problem with these lenses that people need to know about.

I am having the same problem with the Proclear Toric lenses tearing. In two weeks I have had two tear while in my eye and one fall apart as I was rinsing it to put it in my eye. I have worn soft lenses since 1984 and have had a torn lens four times in all those years. I have been wearing Cooper Vision Frequency 55 Toric lenses and it has never happened. My optometrist's staff is saying there is nothing they can do.

I have a Frequency 55 toric lens in my left eye which easily lasts the full month and has not caused me problems. I recently changed from a GP lens in my right eye (after 30 years of wearing them, my "older" eyes are drying out and not tolerating them anymore) and was given a Proclear sphere lens. I have now ripped two of them within the first two weeks. They are so fragile, and I am very careful with them. After 30 years I am obviously and experience contact lens user! I plan to call my ophthalmologist and see if I can switch brands, this is going to get too expensive and I will use up the one box way before the other.

I just received a trial last week of these ProClear toric contacts lenses and I wasn't even able to get the contact lense in my eye before it tore. I've been wearing contacts for 8 years and have never had this happen. I thought that I just received a faulty lense until I came across this forum, Glad I did, I was about to order a year supply tomorrow, seeing how the other contact lens feels great. What a shame...

I am glad to read these comments. I am a long time contact wearer, but trying a trial pair of Cooper Vision toric lenses. The right lens tore in my eye on the third day of use. It is hard to justify the expense with this track record. Very disappointing since my vision was quite clear with these lenses. Go back to the drawing board,
Cooper Vision.

Hi Ann,  Thank you for your feedback.  We want to be able to help.  Please send your information to CC@CVLens.com so we can get more information and contact you directly.

I have just purchased 3 month supply of these lenses after trying lots lenses. I have started wearing my first pair on Tuesday and today is Sunday and i found them torn when I took them out of the solution! They were intact when i placed them in the solution in the evening. They were supposed to last a month! I'm very disappointed and will take them ASAP to the opticians I ordered from! What a waste of money and time! Hope will get my money back!

I've been using the Proclear toric lenses in my right eye and the non-toric ones in my left eye for a few years. When my eye doctor ordered a new six-month supply of lenses recently it took three weeks, instead of the usual two, for the right lenses to arrive and instead of a box of six there was just one sample. It was very thin, uncomfortable to wear and it ripped the first time I tried cleaning it. Meanwhile my eye doctor reordered a box of six, and they arrived after two weeks and they were just like the sample. They were very thin, they wouldn't form a proper bowl shape on my finger and they'd fold in half, and it would take a long time to get them unfolded. After two weeks when I was putting the first one in my eye I saw it was ripped, so I put it a new one, and that afternoon it ripped in half in my eye. I tried putting in a third one and it was folded in half and I was unable to get it completely unfolded. So I gave up on them, my doctor ordered new ones and I'm back to wearing glasses until they arrive. The new ones better not be defective and I better not be expected to pay for them. I'm also sending this information to CC@CVLens.com.

I'm Just wondering if there has been any changes in this brand of lenses in 2014, I have been wearing them for 10plus years and the new ones I have just purchased feel a lot different and very uncomfortable even with out any prescription change.

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