Why do people wear hard contact lenses?

- asks Lindsey from New York

June 25, 2007
This gas permeable rigid contact lens does not contain water like soft contacts, is resistant to deposits, and is less likely to harbor bacteria. CREDIT: [PARAGON VISION SCIENCES, INC.]
This gas permeable rigid contact lens does not contain water like soft contacts, is resistant to deposits, and is less likely to harbor bacteria. CREDIT: [PARAGON VISION SCIENCES, INC.]

Other than being generally awkward, I’ve spent most of my time since I was 13 getting things in my eye–or rather, getting things stuck onto my gas permeable, “hard” contact lenses. Other formative moments have had me blinking on command so friends and gathered revelers could see the tiny, glass-like chunk in my eye move and resettle.

About four weeks ago, when I was yet again ticking off the reasons why I was lucky enough to have thick lenses directly on my eyeball, it occurred to me that I had been reciting the same spiel–a strange eye shape, really really really bad eye sight–for more than a decade.

What if, the science had changed and I no longer needed hard lenses? What if I should have had years of soft contact wearing behind me, and I didn’t know it, because I was blithely tripping along following the advice of the eye doctor I had during my adolescence.

Turns out, he was a smart man (let the record show I never doubted him). For certain vision corrections, rigid gas permeable lenses provide clearer, more precise vision than soft lenses. This is mainly due to structural difference between soft and gas permeable lenses.

Since soft contacts are traditionally made with water, they can actually dry out, causing their shape to warp and preventing clear vision as well as becoming a potential irritant. To stay hydrated, soft lenses draw moisture from the eye, which can lead to dry eyes. Water also binds to tear proteins making contacts attractive to “pollutants,” such as lotions and soaps, which creates a chunky, gritty build-up on the contact.

Rigid lenses, being stiff, don’t change shape when the wearer blinks, so they stay precisely focused. Not only that, rigid lenses, unlike soft contacts, do not contain any water. Because they are made with silicone polymers, rigid lenses are more oxygen permeable, making them healthier for the eyes (though these days, some soft lenses, called “extended wear,” are made of silicone hydrogel–a substance that allows almost as much oxygen to flow through as rigid lenses, and is less water dependent ).

But this is not to say gas permeable lenses are problemless; they, too, have their downside. When you first get them, you can’t just pop them in right away. Rather, they are broken in by wearing them for increasing amounts of time as your eye adjusts to having a new lump of stuff in it (I believe my doctor told me my eyelid had to form a sort-of groove…). Even if you are lifetime wearer, leaving the lenses out for a few days means going through the process of again .

Also, rigid gas permeables must be scrubbed clean, and soaked, nightly–while soft contacts can be worn constantly, soaked or simply tossed. Hard contacts are more expensive too, as are cleaning solutions (up to eleven or twelve dollars a bottle). But if you don’t lose them or crack them, hard lenses last longer (that’s a big “if”).

So, it seems as though “hard” lenses–full of mystery, science, and silicone–still serve an important function for certain contact wearers. Some last interesting facts about contact lenses:

1. Rigid gas permeable lenses are not the “hard” lenses of yesteryear, which were actually made of an oxygen-impervious substance called polymethyl methacrylate–truly “chunks in the eye.”

2. Gas permeables can also be used for nifty technique called orthokeratology, in which the lenses are worn–usually overnight–to reshape the cornea, leaving the patient with 20/20 vision. The effects of this last only one or two days, however, which is probably why it hasn’t caught on with all contact wearers.

*An interesting side-note: if you are wanting the best of both worlds, there is a new contact out with a rigid center, and soft circumference. Check it out

About the Author



Karen Schrock says:

I wore hard contacts my whole life, too, until last spring. The doctor suggested I just give some soft ones a try, because they would correct my vision “almost” as well as gas permeables. Turns out I couldn’t even tell the difference (I mean, I guess my right eye is SLIGHTLY blurry but with both eyes open I don’t notice at all) and I find them much more comfortable than my old ones. I’m converted! I have to say, though, I miss being able to amaze people with the whole blink-and-watch-it-go novelty act, and I also miss having the option to moisten/clean a contact in my mouth when necessary. …Probably not doctor recommended, but don’t even try to pretend you haven’t done it!

An eye doctor says:

GP’s (gas perms) can be made more comfortable if they are made larger. Today’s computer controlled lathes can make better fitting gas perms and larger ones that can tuck under the lids. Lid interaction is what most GP wearers notice. Perhaps it’s too late for most people since soft lenses have already taken over the vast majority of eye doctor’s lens fits.

The Synergeyes lens is one very nice option.

Anastasia says:

I’m glad I’m not the only one who will be wearing the hard lenses still, I insisted upon getting them because I found the soft ones to be awkward and blurry for me. Even so, getting used to them is a real pain.

Alan says:

Well at the age of 55 I was a little fed up with reading glasses and having different strength ones for working on the computer, which is my job, so I now have zwave multifocal RPG lenses. This is my third week, and I really find things blurry WITHOUT my lenses. But my eyes were very, very, tired before I asked for lenses as they were struggling to focus. RGP’s were recommended for their clarity and longevity and so far I’m convinced. But technology is still moving forward and who knows what new things will hit the market in the next few years.
Three weeks is about the norm for getting used to these I’m told, and it seems I’m fairly normal in that.

Steve says:

I wore hard lenses from 1977 to 1994. When I moved and changed eye doctors, the new guy prescribed gas permeable lenses. I found them to be even more uncomfortable than hard lenses, and they didn’t give me the clarity of vision I got from hard lenses. Gas permeable lenses also seemed to be lighter, and didn’t rotate quite as well as hard lenses. They required more intensive cleaning, and picked up way too much protein deposits. When I complained about all this my new optometrist switched me to soft toric lenses, which were comfortable, but didn’t give me near enough clarity of vision. Both gas permeable and soft lenses made my presbyopia bad enough that I had to wear reading glasses to read.
By chance I had saved a very slightly used pair of hard lenses from my original prescription in 1977. I put them in just for fun, and they work so much better than any of the newer type of lenses. I no longer need reading glasses, and I can see distance wise just as well or better than gas permeables.
I have an eye exam next week, and I’m going to demand that the optometrist issue me hard lenses in a duplicate prescription, or I’m going to change doctor’s until I find one that will. I should have never allowed this guy to talk me into going gas permeable in the first place. Sometimes the so called new technology is not the best for everyone.

sallie says:

I was prescribed gas permeable contacts when I was in the 7th grade. I wore them until I was 22. That’s when I decided to try soft contacts since I seemed to be the only person with the GP. I’ve been wearing the soft for about 5 years and I think I’m about to switch back to the GP. I’ve had a difficult time achieving good vision with the soft contacts and recently the fit of my right contact has been very poor due to my astigmatism. I have to constantly blink to keep the contact from fogging up. I have liked the ease of wearing soft contacts: no cleaning, disposable, comfort, etc. but I know that my vision was much better with the GP and it’s totally worth the extra hassle to me. Now I understand why my eye doctor tried to discourage me 5 years ago from switching to the soft lenses. I miss that crisp vision that I had with the GP. I think I can handle the extra care that they require. My sight is worth that.

Russ Tait says:

I have been wearing hard/lenses then the new GP when they were introduced for a total of 35 years Im 67 years old and now wear them all day, used to wear them primarily for sports, they have to be cleaned daily and you must use the right storing liquid or they become brittle and break.

Mark says:

I wore GP lenses for 20 years when I started thinking about LASIK. My eye doc suggested trying soft lenses in preparation for a LASIK evaluation. I was hesitant since I had tried them with another doc several years earlier and didn’t get good correction. Turns out for my nearsightedness + astigmatism there are several new choices in soft lenses. Though it took four trial pairs we got my vision to 20/20. I have never been 20/20 with glasses or GP’s.

My eyes are far less tired at the end of the day, I don’t feel I need to take a day off from wearing contacts once a week (as with my GP’s) and if they are dry at the end of the day my big decision is do I want to walk up two flights from my basement computer to my bathroom to take them out. Now the only reason I don’t put my soft lenses in on some days is pure laziness.

My wife is more nearsighted than I and still wears GP’s and is a bit afraid to change. But she is also experiencing tired eyes and may ask for a trial pair at her next exam.

Contacts are not for everyone. Some people are deathly afraid of putting anything near – let alone on – their eye. Some may not be able to manage the handling regimen. And others have eyes that react crazy to them. I know people in all three categories.

As to which type will work better for you, often the only way to find out is to try. But if your doctor is recommending GP its usually for a reason. For some they work much better at correcting vision.

Andreja Wastl Petrič says:

I have been wearing the hard lenses for 35 years and I am very pleased with them. My first pair was a kind of a phenomenon, as I had it for over 11 years!!! Recently I have encountered some problems because I had to change the , which went under different commercial names through the years and it was absolutely brilliant for my eyes. The producers decided recently that it is not profitable anymore and they stopped making it. I tried many different solutions, as Totalcare etc., but my vision gets blurred after a while, or with other words, lenses become unclear. This pair is only a couple of months old so wearing out doesn’t cut it. I would appreciate your comments or suggestions.

Garrett says:

After 30 yrs and the age factor of reading close up the eye doctor told me to try the new contacts which address the bifocal issue. I have had them for a week now and the issue I am having is putting them in, but more so taking them out. With GAS RP’s they were easy to pop in and out without really having to touch your eye. As of now, I have a swollen red eye because I find the soft very hard to get out. My doctor made the comments that my eye was dry when I took the exam. I am beginning to believe that my eyes have always been dry which is why the soft contact is sticking to my eye…?

victoria says:

I’m 15 years old and have been wearing contacts since i was five. i started out with contacts and glasses together tried just glasses then went to just soft contacts. i loved them because i never knew i wasn’t actually seeing that great. About two months ago my doctor recommended gas perms and i was like ugh. lol. i tried a trial pair and they were extremely uncomfortable and kept falling out. i was getting ready to tell my doctor i don’t care if i don’t see that well i want to go back to soft, when i tried one pair with a new fitting. I LOVE them! They feel just like soft contacts, i see 20/25 which is the best I’ve ever been, and their not that bad to take care of. the only problem is that they got the prescription on one eye mixed up or something so im just wearing one contact for now but that’s OK because when i go back in 2 days im going to tell just don’t touch the fitting. :) gas perms aren’t that bad when you get them fitted right.

Rich Smith says:

I’m 53 years old and have had the same pair of Gp’s for 26 years, not bad. I had “lost” one about 4 times over the years but was always able to find it somehow. Finally lost one two weeks ago at my 16 year old daughters softball game. I’m in the market for a new pair and will defineatly go with the GP’s. P.S. I’m surviving now by wearing one of the first pair I got 28 years ago. Hard with the little laser holes.

Anita G says:

I’m 22 years old, and I’ve been wearing soft contact lesnes since I was about 15. I’ve always loved them, and never had a real problem with them. I have really high precription, and recently moved abrod. My new eye doctor suggested hard contact lenses because I was constantly getting eye infenctions.

Ive been with GP for a week, and Im having A VERY HARD time adjusting but I really do see so much better

Stevo says:

I wore soft for years. Uncomfortable at night and poor vision. Changed to GPs, excellent vision. Now wearing high oxygen Menicon ‘Menifocal’ bifocals – work perfectly and are more comfortable than soft. Can be worn for up to a month. HIGHLY recommended.

debra says:

I have wearing hard contacts since the 7th grade. And that has been 38 years ago. I wore the old hard lences until 18 years ago, then changed to gas permebail. I have no problems with them I did have bifocles but now I am doing the one eye sees to read and the other is for distance. It is working well, but I have come to the reality I am seeing impaired and will never see 20-20 so what i am able to see is a blessing

Amber says:

I;ve been wearing them for 3 years, on the comments some of you said you’ve been wearing them on during the day, aren’t you suppose to wear it at night? Thats what I do.

Cathi says:

I am almost 62 years old and have been wearing contact lenses since 1970. I got my first pair of hard contacts in ’66 but tried to get through the ‘adjustment’ week in one day and did considerable damage to the top layer of my eyes. Fortunately it was repairable in a few days with medication and patches over my eyes but it scared me away. Not till I read an artical in Readers Digest on the gas perms—or was it the “new” soft lenses?— did I try them again and inside of a few days I was wearing my contacts every day with no problem. I didn’t get the gas perms right away tho, perhaps not till the mid ’70s. I have looked into soft lenses and have heard many stories about the transition taking possibly years because of the “relaxing” of my eyes from conforming all these years to rigid lenses where the soft ones do not shape the eye and I would be replacing the Rx every few months to correct the change.
After reading some of these posts I see most folks say their vision is also not as sharp with soft lenses.
I have no trouble caring for these RGP’s and I did have trouble inserting and removing the soft ones when I did try them. I realize it takes practice.
I do have a question for Rich Smith—what kind of lenses were the ones you mentioned—-with laser holes? Interesting.
I now have bifocal gas perms and the first week or so they were great but I am right back to wearing reading glasses even with the contacts in. They were more expensive and apparently not suited for me. I will go back to single vision GP’s.

Victoria says:

I have no choice but to wear GP lenses now. I’m 24 and started wearing soft contact lenses when I was 13. About a month ago I developed Keratitis from wearing soft contact lenses for so many years. The soft lenses caused a severe lack of oxygen from getting into my eyes which left scars on my corneas. The scars lead to nerve damage which eventually leads to blindness. Luckily, my Kerstitis was caught before any damage to my vision occurred, although I’ll always have scar tissue. Now, I have no choice but to wear glasses, get surgery, or wear GP lenses. I got fitted for GP lenses the other day but they seem so uncomfortable (not to mention expensive). I’m really hoping that with time I’ll be able to get used to them. I really don’t like wearing glasses. My eye doctor told me a lot of people aren’t able to make the transition from soft lenses to hard lenses. He said a lot of people find it to be too uncomfortable. Hopefully that wont be the case with me!

GG says:

Get the hard contacts! My half brother who has been wearing hard contacts for over 40 years. He was about 18 years old when he started wearing contacts. He has had the same prescription als. Twoyears ago he got intoxicated and lost one lense. He actually started to use one lense for distance and his natural eye for things up close. His eyes started to grow acustomed and he told me he loved it. Unfortunately he also lost the other contact about a year later. He could see TV,so my mom gave him a pair of her glasses to see distance. up until that time his opthamologist told him his eyes had not changed because the hard contact helped him retain the shape of his eye. Now he has gone at least 4months without contacts due to his finances and his eyes are changing drastically. so be careful what you start off with for the future of your vision

Yoleitoinia says:

I am 24 and wore soft contacts from the ages of 14 to 20 before I began to have serious problems with dry eyes and blurry vision in soft contacts. I am going to try some custom made gas permeable contact lenses and see how I see in those.

tlb says:

i started at age 15 with gp. my first pair last 19 years..lost them down drains, dropped on bar floors and always found them. had a period of years wearing my daughter and mom’s old gp and have had my current set for 6 years. now the over 40 thing is hitting and i’m needing reading glasses..just started working in a steel factory and decided to get prescription bifocal safety glasses..they are terrible. my distance is totally gone. eye doctor is recommending me try monovision contacts so i think i will give that a try with some tighter to my eyes regular safety glasses for work..i miss seeing crystal clear at all distances.

zaiba says:

I am 36yrs old.I had an eye infection a few years bach due to which i developed scars on my cornea. at that time I came to know that I had karatoconous as well. now i am using glasses, but these are not doing well for my vision. my doctor suggestd hard lense but many people told me that hard lenses may damage my eyes thats why I opted to wear glasses. I want suggesion wehter i should go for hard lenses or not?please tell me its pros and cons

becky says:

I as well have keratacones. Glasses in the end did nothing as my eye doctor said to me glasses from this point on are useless and told me about hard contacts. It took almost a year to be fitted in the right lenses but it was so worth it. Ill admit it took me quiet sometime to get used to them but now I wear them all the time. I can’t see without them. Like I said it takes awhile to get used to them but in time you will and you will realize being able to see clearly is well worth it.

galal says:

steep by steep treating case with keraticounse with hard contact lens
i hope that if possiple vidio

Natalie says:

I’ve worn GP for 12 years. I’ve thought of switching to soft often, as it seems the rest of the world wears soft lenses. However my mom used to work for an eye doctor and stresses often how much better GP are for your eyes. To those who are new to them, research your eye doctor. I recently swit,he’d eye drs and found out my old lenses weren’t fit correctly and did some minor damage that will more than likely correct itself. GP/hard lens fitting is a science, so find a dr who educates his/herself appropriately. My next step? Lasik! :)

Abeer says:

I can so relate to you as far as bad vision goes and explaining my thicker than thick glasses even with the latest advancements. I wore soft lenses through most of my late teens and then I had to give them up because they no longer provided clarity. Also because my astigmatism grew.
Then one eye doctor I was seeing told me I shouldn’t be wearing contacts at all which bummed me out a little. I liked wearing them socially if nothing else. :)
So I switched doctors for other reasons as well. He suggested I wear GP. I hadnt even known they existed and so when I got my pair I was surprised at how hard they were. They had to numb my eyes for me to get into them. I have been wearing them on and off for 2 months now. We are still working on getting the number right. I still can’t see clearly.
I feel like it will fall when I am driving and I turn to look in my blind spot when changing lanes.
So my question to all of you long term wearers is, how often do they fall out?

Elizabeth says:

I suffer from Sjogens and have astigmatism plus nearsighted. I’ve tried accuvue moist for astigmitism but I can only last 3 hours before my eyes are painfully dry. My eyes are also very sensative to chemicals and preservatives. I can’t even use soft contact rewetting drops. What would the best lens be for my extremely dry eye with astigmatism and nearsightedness be? Is there a cleaning system that system that uses heat instead if chemicals? Last, is there a colored contact for extremely dry eyes for astigmatism plus nearsightedness? I’ve already tried Accuvue Moist for astigmatism, which are the lens I only can tolerate 3 hours.

Jay says:

@ ABeer: Your GPs shouldn’t fall out like that. When I first got mine, the one on my right eye did that once. I went back to the eye Doctor and he worked his magic and refitted it. The lense never fell out again. Ok, maybe on another occasion when a guy punch me in the face. But yeah Bro, tell the doc that they’re slipping off. He should be able to fix that and the clarity. GPs gave me a whole lot of better vision than the soft contacts.

Aziza says:

I am 23 and I have been wearing GP lenses for 6 years now and they were really great during the first years (I changed them twice since they last longer than soft lenses do),however, the problem is that it seems that I had an eye infection ,allergy ,and astigmatism which made wearing them really uncomfortable in the right eye to the extent that I could barely open my right eye in the glare. I confess that they changed my life from poor vision (-17) into 20/20 but I still suffer from some headaches, lack of concentration & fatigue and I really need a surgery. What do you recommand?

Julie says:

I have worn hard and later gas permeable lenses for the last 51years without any problems! My sister told me they eventually badly scar the cornea. Is that true? Apart from the occasional speck of dust in my eye I have never had the slightest problem (I turned 70 last month)

PatB says:

I’ve worn some form of hard contact lenses for 40 years and never had a single problem I recently had cataract surgery with lasik and although my vision post surgery is significantly better, I’m not at 20/20. After surgery I tried soft lenses and HATED the blurriness and trying to get the soft lenses in and out of my eyes. I’m back to hard lenses and enjoying my crisp, clear vision.

April A says:

I’ve been wearing gp contacts since I was 12. I’m 43 yrs old & love them. It took some adjusting in the beginning but I’m so glad that I stuck through the adjustment period & became comfortable wearing them. My daughter who is 13 wants contacts & I’m hoping she will be able to get fited with gp’s. For some reason the eye dr office is saying she will most likely get soft, but I’m curious as to why. Time will tell.

Katrina says:

I am wearing rigid gas-permeable contacts now and they are the best thing that ever happened to me. I am 53 years old and I have been wearing glasses since I was a five-year-old girl. Since I had very high myopia (and astigmatism) which steadily increased as I was a teenager, the RGP’s provided clear vision that soft contacts couldn’t because my astigmatism was so bad. But, I was originally fitted with regular PMMA hard contacts in the 1970s, and I would have very blurry vision when I popped them out and put my glasses on. My eyes would take HOURS to recover from the old hard contacts. Now, I don’t even wear my glasses anymore (unless I am at home alone) because they are so thick.

Luke says:

RGP are better for long term use, just look at the comments people been wearing for 40 years, I have been wearing for 28 years!! But now past 40 its getting little uncomfortable prob cos of the computer aircon job i do, i tried soft but the just gave red eyes, they are more comfortable but not as safe, you should check eith a doc.

Diana says:

I started long ago with soft lenses but soon moved to RGPs for better clarity. I’ve worn them for about 30 years and was initially advised that I could wear them for seven days–even overnight–then clean them. I have never had any problems with that schedule. I currently use bifocal lenses and also have monovision (one for near vision and one for far vision) to correct presbyopia, near-sightedness, and astigmatism. I love my RGPs!!!

Diana says:

I started long ago with soft lenses but soon moved to RGPs for better clarity. I’ve worn them for about 30 years and was initially advised that I could wear them for seven days–even overnight–then clean them. I have never had any problems with that schedule. I currently use bifocal lenses and also have monovision (one for near vision and one for far vision) to correct presbyopia, near-sightedness, and astigmatism. I love my RGPs!!!

Tony says:

I recently got RGP lenses this summer. I made a horrifying mistake one morning when I took them off and one of them fell down the drain! Worst $250 mistake of my 18 years haha! Other than that, I love the effect of the reshaping of the cornea. However, if I skip a day, the blur comes in and the squinting gets real. I wish there was a way it’d last longer than it does, but that’s reality I guess.

Paula B. says:

I tried RGPs for 2 weeks and the fit was great, but I never had clarity and my presbyopia was not
Improved at all. I’m only slightly nearsighted with presbyopia at 51.
I’ve worn glasses for about 20 years, since all eye doctors told me that I would not be able to see well with contacts. I tried soft contacts two or three times and the cost put me off most of the time. Now, the presbyopia has complicated my prescription. I have progressive glasses and I can see great except the fish bowl effect at the computer, so on to RGPs and back to soft contacts. Too much glare at night to drive with RGPs and no correction of presbyopia with +3.00 add power. The glare was like fireworks. My next choice was a more expensive hybrid with more variations in add power, soft and rigid in one. Cost a factor again so, back to a multi focal soft lens. The hybrid has to be replaced in 6 months. My insurance allows extra for RGPs, but not enough for two pair a year. I don’t want to be tied to glasses, readers at +1.00 or progressive eyeglasses.

vladimir says:

Contact lenses wearer fellows, ´m 50 years old and I have been wearing “contacts” (rigid, impermeable) lenses since I was 15 (1977). Few months after start wearing CL I decide to wear them continuously, take them sporadically to clean, when my vision is blurred due to biofilms deposits on their surface. Since that date, I had not been in serious problem with my eyes and myopia is like it was at 15 years old. Before use contact lenses, I used to wear glasses (since 7 years old) and my myopia was greater every 6 months. I thought my case was unique, or very rare, but recently a new colleague have the same experience for about 15 years, wearing rigid non-permeable contact lenses continuously.

roderick jacob says:

Why was I told by my optometrist to put a few drops of saline in my lens before inserting? I’ve been doing this for over two ears but I’ve not come across this anywhere or on the product instructions. Can I use it dry? I was told not to.

Anna Mellark says:

RPG’s are so much easier. I’ve used them for two years now, and the only problem I had is that my eyes got too dry (I’m a uni student, so this was only inevitable) and the lenses started to scrape my cornea. However, it was nothing that couldn’t be fixed, and my eyes are back to normal thanks to eyedrops and a new set of PRG lenses (they’re slightly blue, not completely clear like my previous lenses).

GP lenses have less work and hassle, not to mention are significantly better on finances, but RPG’s are absolutely worth it- your sight is worth the money and time.

I’ve been looking into LASIK surgery, but so far it hasn’t appealed to me, though I will probably get it done.
The only recurring issue with RPG’S is that the vision only lasts for a day or two after taking them off- which I think it quite short since the lenses reshape your cornea, and the cornea can’t go back to its original shape that easily, can it? But I guess that’s how it is.

Barbara says:

Wow! I totally agree with the comments on the hard non-gas permeable lenses!!! I wore my 1st pair of contacts (hard) for 15 years with no problems AND they corrected my astigmatism and my sight was always better when I took them out! I lost them and my new opt. Recommended gas-permeable….. I had nothing but trouble and my vision deteriorated! Now, they tell me I can’t even get the original Hard Non-gas permeable anymore as the no longer make them!!! Is this true? If anyone knows how/where I can. get the ‘old-fashioned’ ones….Please let me know!!! Thanks ❤ Barbara

How long does one have to not wear semi-rigid contact lenses before cataract removal.

Jheel says:

I’ve studied optometry for four years and when your doc tells you hard lenses are not good, they do it for a reason. I’m talking about the traditional hard lenses here (PMMA), not RGP lenses.

Common sense suggests living cells require food, water, and oxygen to survive (unless they are anaerobic cells which do not use oxygen for metabolism)- you don’t need to be an optometrist to understand this concept, this is high school Biology.

Your corneas are avascular (have no blood vessels) and are made of living aerobic cells. From the above argument, it’s obvious that these cells will need the three primary prerequisites of life- food, water, and oxygen. Without blood vessels, the body must provide an alternative way of delivering these to the corneal cells. It does so using a tear film.

The cornea is perpetually covered by a thin layer of tear, which brings food and water to the corneal cells, and removes metabolic excretory products from them.

The third requirement, Oxygen, is a bit complicated. Tears don’t enter the cardiovascular system (lungs/ heart), and neither do they contain haemoglobin, hence the oxygen you breathe, cannot be delivered to the eyes. The tear film acts as a “mediator” for oxygen delivery. Oxygen tends to freely dissolve in water (if this wasn’t the case, marine life wouldn’t be possible-fishes breathe oxygen dissolved in water).
When your eyes are open, atmospheric oxygen dissolves in the tear film, and is absorbed by the corneal cells from the tear film. When your eyes are closed, blood vessels on the inside of your eyelids diffuse oxygen thru the tear film to the corneal cells.

Hard lenses are impermeable to oxygen. When you place a hard lens on your cornea, the tear film under the lens (between the lens and your eye) cannot absorb oxygen from the atmosphere (or from the blood vessels on the inner side of the eyelids when your eyes are closed). A situation known as “Chronic Hypoxia” develops, and your cornea becomes vulnerable to infections. If Hypoxia is bad enough, the corneal cells start to die (Necrosis, unprogrammed cell death, can leave a scar on the cornea). The body reacts and tries to compensate and prevent cell death by producing new blood vessels (neovascularization) that infiltrate the cornea. The blood vessels you see on the white part of your eyes- imagine them growing into the colored part of the eye.

If a blood vessel forms on top of the pupil, it will block light and you won’t be able to see at all. This is rare though. The bigger problem is that these new blood vessels tend to be “leaky”. They can leak and pour out lipid and other stuff from the systemic blood supply into your cornea. This will cause a permanent “haze” on the cornea, and your vision will be severely impaired. The only known way to recover from this is a corneal graft from a donor (some people incorrectly refer to this as an eye transplant surgery).

You cannot block out oxygen. If you do, you are causing harm. Maybe you don’t have symptoms, but nevertheless, being symptom free is not necessarily the same as being problem free- a careful investigation by your optometrist can detect these problems and he/she can then take appropriate steps to mitigate the issue before you experience the symptoms (i.e., re-fit you with an RGP, or a Silicone Hydrogel soft lens, use drugs to control infections and prevent further infiltration of blood vessels, etc).

To sum it up, DON’T use old style (PMMA) hard lenses even if you have used them for 30 years without any problems and they give you better visual acuity than RGPs. This is like tobacco smoking- there are people who have lived to be a hundred and smoked 20 cigarettes every day, but this doesn’t mean cigarettes are safe.

Mick Conley says:

I’ve been wearing hard contact lenses for over 50 years, I asked my doctor should I change to soft lenses. His reply was, if it’s not broke don’t fix it. He was amazed that I had them that long. Once a year I have them polished when I get my yearly check up. Last year I got new ones, worried that they would be different, they were great, slightly lighter then my old ones, very comfortable. Guess I won’t be changing after all.

George Frederick says:

Now 58. Got hard contacts about 15 and found them difficult to wear at first. Swapped to GP and found I could wear them for days at a push, and my vision was pin sharp even with -8 vision. A month ago I started a trial of soft lenses which I hated at first. The left eye has an astigmatism which seemed unable to focus BUT tried some soft multi focal and they are great. Both eyes have great distance and close up focus, and my left eye doesn’t need so much time in the mornings to “get going”.

After wearing GP contacts for so long, even my optician predicted I wouldn’t change, but I just ordered 3 months worth of the soft multi focal contants. My only worry is the stories I’ve been told about higher risk of infection with soft, and the ongoing costs. It will be nice if I loose one to just open next month’s rather than wait a week for a new GP lense to be made. Swings and roundabouts.

Jamie M says:

I want to be sure everyone knows about the possibility of Ptosis as a result of wearing types of hard lenses for many years.
I am 57 and have been with the same eye doctor (well, the original eye doctors have now retired, but they have passed the torch to new ones in the same office) wearing RPG, or different forms of them, since I was 14 years old. I have never had a problem with them, but have also never tried soft lenses. I am now told I have weak eye muscles (Ptosis) from wearing types of hard lenses. I now need to have eyelid surgery to tighten the eyelid muscle so my eyes don’t look half closed like I’m stoned all the time. This is pretty upsetting and I wish I was told that this was a possibility. I might would have looked into soft lens options years ago.

Alex says:

Great article! Contact lenses are used so frequently and widely, that they are turning out to be the source of infections such as viral and bacterial conjunctivitis. People are getting used to wearing them just for fun, to get a particular eye color. This has to be done with care.


I know this is late in the game, but at 63 years old, I have worn hard, then RGP’s for over 40 years. About 20 years ago went to multi-focal RGPs. I love them!
I have had no eye problems, and don’t get checked often, but my eyesight has improved (distance vision) while, of course, my reading vision is getting worse with age. I can take out my lenses and see really well for about a week, then it slowly gets worse. My current RX for distance is so low that I probably don’t need correction for far-sightedness. When I was 10, my vision was 20/200, now it’s probably 20/60. I am supposing that constantly wearing the RGPs (10-12 hrs day) has permanently changed the shape of my eye.
For the record, just went to an ophthalmologist and was told my eyes are really healthy–surprised me because I’m not really overly cautious about my eye care. Now I am basically wearing the lenses for close vision, because that is getting worse. Just had my rx changed because the bifocal needed to be stronger-was using reading glasses for the last few years with the contacts.
I found this thread when googling if RGPs can improve eyesight with age, which is the case with me.

Lise Wåsjø says:

I am looking into the possibility of helping wearers of hard contacts, making it more comfortable to insert and take out. However I find it hard to find satisfying information about hard contacts online, and why they aren’t more widely used, when it seems like it for a lot of people will improve their eyesight significantly better than the soft ones. So I’m interested to hear about peoples experience with the hard contacts, and if they struggle with the insertion and taking them out.

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