gordon@cae780.UUCP (Brian Gordon) (11/20/85)
Due to the degree of astigmatism I have, there are no soft contact lenses I can
use. After 30 years with glasses, I have gotten hard lenses -- which are
VERY different than those I tried (and gave up on) 25 years ago.
These are the gas permeables, and new ones, at that. These are even more gas
permeable than the soft lenses approved for extended wear, and the manufacturer
has already applied to the FDA to have them approved as extended wear also.
My eye-care professional (an optometrist) is quite "thrilled" with the fit,
etc., exclaiming how this type of lens is "just made for" my eyes. I have had
remarkably little trouble getting accustomed to them.
He is, however, also quite conservative. He recommends that, until the FDA
agrees with the manufacturer, the lenses be worn for no longer than 13 hours a
day, to give the cornea the other 3 hours at normal oxygen levels.
Is there anyone else out there with the background/experience to either agree
or disagree with that advice? Keeping up with both lenses and glasses is more
hassle than either separately!
FROM: Brian G. Gordon, CAE Systems Division of Tektronix, Inc.
UUCP: tektronix!teklds!cae780!gordon
{ihnp4, decvax!decwrl}!amdcad!cae780!gordon
{nsc, hplabs, resonex, qubix, leadsv}!cae780!gordon
USNAIL: 5302 Betsy Ross Drive, Santa Clara, CA 95054
AT&T: (408)727-1234
Down 69 1/4 pounds and holding ...chris@leadsv.UUCP (Chris Salander) (11/21/85)
In article <1600@cae780.UUCP>, gordon@cae780.UUCP (Brian Gordon) writes: > Due to the degree of astigmatism I have, there are no soft contact lenses I can > My eye-care professional (an optometrist) is quite "thrilled" with the fit, > I have gone for years without considering contacts because they could not be used for astigmatism. Now that has changed, but I have heard that the sort of contacts that you must wear must keep a specific orientation; i.e. you cannot but them in just any way. They are suppose to be heavier on one end so that that end is always down, keeping them oriented properly. This is the story I have heard. Have people found this to be true? (And how can you stand to put things on your eyes?) - Chris Salander
sdyer@bbncc5.UUCP (Steve Dyer) (11/22/85)
>He is, however, also quite conservative. He recommends that, until the FDA >agrees with the manufacturer, the lenses be worn for no longer than 13 hours a >day, to give the cornea the other 3 hours at normal oxygen levels. > >Is there anyone else out there with the background/experience to either agree >or disagree with that advice? Keeping up with both lenses and glasses is more >hassle than either separately! My only experience is as a hard-lens wearer for 10 years, most recently with gas-permeable hard lenses. I don't think mine are as porous as yours. Once I was accustomed to hard lenses, I found that I could wear them for much longer than any reputable optometrist would recommend. Right now, my wearing times range from 12 hours/day all the way up to 17-18 hours/day, with about 13-14 hours being average. My regular check-ups have never revealed any edema or swelling due to oxygen deprivation. I actually found that my old hard "gas-IMpermeable" lenses were more comfortable, and I could wear them longer, probably because the newer lenses are so hydrophobic: they don't want to be wet by the tears, and this causes irritation and mucus buildup. Most people use their level of comfort along with feedback from initial checkups to gauge whether they are wearing their lenses for too long. With that said, given that you are using a new product, it is only reasonable to follow your doctor's advise. 13 hours is a LONG TIME. What is more, you are kidding yourself if you think that wearing contacts means you don't need a pair of glasses, at least if your vision is fairly bad. I keep my glasses next to my bed for late night and early morning reading, and when my eyes are tired from wearing lenses and need a "breather". -- /Steve Dyer {harvard,seismo}!bbnccv!bbncc5!sdyer sdyer@bbncc5.ARPA
chai@utflis.UUCP (Henry Chai) (11/25/85)
In article <1600@cae780.UUCP> gordon@cae780.UUCP (Brian Gordon) writes: >Due to the degree of astigmatism I have, there are no soft contact lenses I can >use. After 30 years with glasses, I have gotten hard lenses ... > >[... My optometrist] recommends that, until the FDA >agrees with the manufacturer, the lenses be worn for no longer than 13 hours a >day, to give the cornea the other 3 hours at normal oxygen levels. I am also wearing new gas permeables (because of my astigmatism). My optometrist's advice was to wear my lenses for as long as they are comfortable. This is usually 13 - 16 hours or so for me. There has been a few occasions when I fell asleep whilst having the lens on, and when I woke up boy do I feel the lenses like rocks under my eyes! -- Henry Chai, just a humble student at the Faculty of Library and Information Science, U of Toronto {watmath,ihnp4,allegra}!utzoo!utflis!chai
chai@utflis.UUCP (Henry Chai) (11/25/85)
In article <697@leadsv.UUCP> chris@leadsv.UUCP (Chris Salander) writes: > I have gone for years without considering contacts because they >could not be used for astigmatism. Now that has changed, But this is nothing new! several years ago I had hard lenses fitted that took care of my astigmatism. Where have you been hiding? :-) >that the sort of contacts that you must wear must keep a specific >orientation; i.e. you cannot but them in just any way. They are suppose >to be heavier on one end so that that end is always down, keeping them >oriented properly. These are called weighted lenses. You put them in as with other contact lenses but they will keep their 'orientation'. >(And how can you stand to put things on your eyes?) How can you stand to be so narrow minded? 8-) Just because you haven't tried it doesn't mean it can't be done. -- Henry Chai, just a humble student at the Faculty of Library and Information Science, U of Toronto {watmath,ihnp4,allegra}!utzoo!utflis!chai
speaker@ttidcb.UUCP (Kenneth Speaker) (11/25/85)
In article <697@leadsv.UUCP> chris@leadsv.UUCP (Chris Salander) writes: > > I have gone for years without considering contacts because they >could not be used for astigmatism. Now that has changed, but I have heard >that the sort of contacts that you must wear must keep a specific >orientation; i.e. you cannot but them in just any way. They are suppose >to be heavier on one end so that that end is always down, keeping them >oriented properly. This is the story I have heard. Have people found this >to be true? (And how can you stand to put things on your eyes?) > > - Chris Salander Yes, the lenses are thicker (hence heavier) on the bottom. This tends to keep them oriented properly. This mechanism is good for correcting up to about 2.5 diopters of astigmatism. I have a little over 2 diopters in each eye and the correction is less than ideal. The problem is that you are not always oriented vertically! Try to read in bed, with your head proped (at an angle) on your hand. Or go to the gym and do some "roman chairs" or decline presses, where you invert the body. Try standing up immediatly after doing that invertion! But, I have VERY sensitive eyes and have never been able to wear hard lenses, gas per- miable or otherwise, so I put up with it. How can you stand to put things on your eyes? You get used to it.... --Kne
shaprkg@sdcrdcf.UUCP (Bob Shapiro) (11/27/85)
In article <697@leadsv.UUCP> chris@leadsv.UUCP (Chris Salander) writes: >In article <1600@cae780.UUCP>, gordon@cae780.UUCP (Brian Gordon) writes: >> Due to the degree of astigmatism I have, there are no soft contact lenses I can >> My eye-care professional (an optometrist) is quite "thrilled" with the fit, >> > > I have gone for years without considering contacts because they >could not be used for astigmatism. Now that has changed, but I have heard >that the sort of contacts that you must wear must keep a specific >orientation; i.e. you cannot but them in just any way. They are suppose >to be heavier on one end so that that end is always down, keeping them >oriented properly. This is the story I have heard. Have people found this >to be true? (And how can you stand to put things on your eyes?) > > - Chris Salander I don't understand what you are talking about. I have worn contact lenses since 1959. They are the old-fashioned hard lenses. I put them on when I get up in the morning and take them off just before going to sleep. The only restrictions I have encountered are - you can't swim with them, you can't sleep with them, you have to use sunglasses in bright sunlight, if it is windy you have to be careful not to get dirt in your eyes, and they can really be a drag if you are extremely tired or stay up very late (like all night). In the latter case I simply take them out for a while. As for astigmotism I understand that hard lenses correct it in a natural fashion. I believe astigmotism is a distortion in the curvature of the eyeball. Hard contact lenses tend to "suck" the eyeball to conform to their curvature and thus correct the astigmotism. I believe that is the reason that I can see perfectly clear after wearing my lenses for a while and then taking them off, but I don't see well when I get up in the morning. After you take the lenses off the eyeball starts to relax and return to its original distorted shape. So, while it is probably true that there is no refractory correction for astigmtism it can be corrected. Although I am unfamiliar with soft lenses. I wouldn't be surprised if they had a problem correcting astigmotism as they probably can't suck in the eyeball like a hard lens. As for your comment about orientation of lenses. I believe this applies only to bifocal and trifocal lenses. The lenses are weighted so that the reading portion goes to the bottom and the distance to the top (similar to eyeglasses). I would normally require bifocal lenses but I simply correct my distance vision and wear glasses to read with. Therefore my lenses do not have to be oriented. Finally, the problem of putting something in your eye is no different than the problem of sticking a needle in yourself when you are a diabetic. You simply look at the alternative. My optometrist likes his patients to hate to wear glasses. Thus, they will put up with the initial inconvenience during the training period and not chicken out just because it is a little uncomfortable at first. When I got my original lenses, I would have done almost anything to get rid of my glasses, and I suspect that is why I have had such a successful time with my lenses.
gordon@cae780.UUCP (Brian Gordon) (11/27/85)
>> I have gone for years without considering contacts because they >>could not be used for astigmatism. Now that has changed, but I have heard >>that the sort of contacts that you must wear must keep a specific >>orientation; i.e. you cannot but them in just any way. > >Yes, the lenses are thicker (hence heavier) on the bottom. This tends >to keep them oriented properly. This mechanism is good for correcting up >to about 2.5 diopters of astigmatism. Let's see how far an amateur can insert his foot into his mouth. (I have no medical background, but great personal interest in recent developments in contact lenses.) "Typical" astigmatism can be thought of as a systematic irregularity of the surface of the cornea. Eyeglasses "correct" for it by bending (i.e. distorting) the light as it passes through, so that the redistortion by the cornea brings it back to its original path. This involves a cylindrical correction along an appropriate axis in the lens. Soft contacts use the same technique, but have the additional problem of keeping the lens properly oriented so that the axis of correction is in the right place. One technique is to "weight" the bottom edge, allowing gravity to help keep the orientation. An alternate method is to thin the top and bottom, so that the eyelids do the work (by migrating the lens so that the thin parts are hit by the lids, leaving the thicker center band where you want it). There are presumably different limits to the degree of astigmatism that can be corrected while still allowing either type of positioning to be used. Hard lenses use a completely different technique. As long as the source of the astigmatism is the eye surface (this covers a high percentage of cases), the hard lens, in effect, replaces your cornea -- your effective cornea is the cornea/tear-layer/contact-lens package, and its surface is not distorted. Thus, the astigmatic correction is "free" -- not even part of the prescription. This is obviously an oversimplification of details, but, I believe, essentially accurate. The newest "ultra permeable" hard lenses seem to have a limited geographical distribution so far, as I have received several requests asking for more specific pointers for their eye-care professionals to follow-up. There are at least three vendors, and the brand names are all of the form "xxxxx 39", the "39" apparently describing the material. The ones I have are "Ultraperm 39", by Alcon. They are more permeable than the present extended wear SOFT lenses, which makes them about twice as permeable as previous gas permeable hard lenses. They are also significantly thinner than some older lenses, making adaption much easier -- but they are still hard lenses, not as easy as soft ones. If you couldn't tolerate hard lenses a couple of years ago, times may be different now ... FROM: Brian G. Gordon, CAE Systems Division of Tektronix, Inc. UUCP: tektronix!teklds!cae780!gordon {ihnp4, decvax!decwrl}!amdcad!cae780!gordon {nsc, hplabs, resonex, qubix, leadsv}!cae780!gordon USNAIL: 5302 Betsy Ross Drive, Santa Clara, CA 95054 AT&T: (408)727-1234
seifert@hammer.UUCP (Snoopy) (11/28/85)
In article <1600@cae780.UUCP> gordon@cae780.UUCP (Brian Gordon) writes: >These are the gas permeables, and new ones, at that. These are even more gas >permeable than the soft lenses approved for extended wear, and the manufacturer >has already applied to the FDA to have them approved as extended wear also. >He is, however, also quite conservative. He recommends that, until the FDA >agrees with the manufacturer, the lenses be worn for no longer than 13 hours a >day, to give the cornea the other 3 hours at normal oxygen levels. > >Is there anyone else out there with the background/experience to either agree >or disagree with that advice? Keeping up with both lenses and glasses is more >hassle than either separately! Yours fit the first time? Must be nice! Okay, time for definition of terms. Correct me if I'm wrong, but doesn't "extended wear" mean they're okay to wear for days at a time? (as opposed to meaning you can wear them for 16 hours instead of 13) I've been wearing standard hard lenses (not gas permeable, no little holes, but *standard*) for 10 years <creak> <shuffle> and I wear them all day, usually ~16 hours, but sometimes more. Had them in 19 hours the other week, with no ill effects. (other than feeling rotten from missing sleep) What usually causes problems is suddenly jumping the time up several hours. And smoke is real bad news. I hurt my eyes a lot more from reading so much (and CRTs are a lot worse than ink on paper), than I do from wearing contacts 16 hours a day. If your eyes are perfectly healthy other than needing corrective lenses, your lenses fit correctly, you're not around smoke, dust, chemical fumes, etc. I would say you're safe in SLOWLY increasing your wearing time. (but remember, I'm not your doctor!) If you do increase your time, do it slowly. The pain resulting from increasing it too fast is absolutely unbelievable. Disclaimer: I'm a Unix hacker, not a doctor. Got that? Good! Snoopy (ECS Ronin #901) tektronix!tekecs!doghouse.TEK!snoopy
grm@drutx.UUCP (Geraldo Ramon de Martine) (12/02/85)
Has anyone had any experiencs with a new gas-permeable hard contact lense called "Boston-4" (or something like that)? I heard a story last week about this "revolutionary" hard lense and I am curious. Anyone know how thay differ from other gas-permeables? Any differences from "Cibas" (supposedly another type of gas-p)? (net or e-mail is fine!) -- mail: ihnp4!drutx!grm
suze@terak.UUCP (Suzanne Barnett) (12/04/85)
> Has anyone had any experiencs with a new gas-permeable hard > contact lense called "Boston-4" (or something like that)? I heard > a story last week about this "revolutionary" hard lense and I > am curious. Anyone know how thay differ from other gas-permeables? > Any differences from "Cibas" (supposedly another type of gas-p)? > > (net or e-mail is fine!) > -- > mail: ihnp4!drutx!grm When I got my current set of contacts, not quite 1 1/2 years ago, my eye doctor discussed the Boston lens. His opinion was that it was overpriced and not that different than other gas permeable lenses. The key factor in contacts, according to him, is the quality with which they are ground. My contacts are from a small local manufacturer. On the other hand, the Boston solutions, both cleaning and conditioning (in other brands known as wetting), are much more comfortable than standard solutions. I will never switch back to any of the standard brands. The cleaning solution really cleans! You can even see the suds. And the conditioning solution really lubricates. It is slightly "oily" feeling, or actually more of a "gel" feeling. These solutions can be used with any type of hard lens, including all types of rigid gas permeable lenses. -- ************************************************************** Suzanne Barnett-Scott uucp: ...{decvax,ihnp4,noao,savax,seismo}!terak!suze phone: (602) 998-4800 us mail: CalComp/Sanders Display Products Division (Formerly Terak Corporation) 14151 N 76th street, Scottsdale, AZ 85260
donn@hpfcla.UUCP (12/07/85)
I've been wearing conventional hard lenses about 18 years (since '67 or so). Most of that time has been with "fenestrated" lenses (with a hole in the middle (that fascinates my daughter)). I can wear them all my waking hours (barring a *really* late night) here in Colorado (where I'm told normal air (O2 concentration) (as opposed to that thick stuff flatlanders have :-) ) and dryness is a bit rough on contacts. I'm told I have astigmatisim rather badly (I should, it runs in the family), but since all I wear is hard lenses, I havn't noticed. (Nor has my prescription changed since I got contacts.) The ability to wear hard lenses for extended periods appears to be tied to the fit: there are the lucky few who get good fits, the less lucky many who don't, and the *very* lucky (or should I say smart :-) ) who have found an optician that gets a good fit most every time. I believe I'm in the last category: there are a small number of (half a dozen?) opticians who make their own lenses, and have found out how to repeatably manufacture lenses with a good fit. I deal with one of them (and no, I don't get a cut for saying this), and I can be assured that if I lose a contact, I can get a replacement by mail that will fit *exactly* as well as the one I lost. (And they fit so well I can swim with them and not lose them, but they're still comfortable (although I *don't* swim with them without goggles)). You'll note I said "by mail". The optician is in Honolulu, a bit of a way from Colorado, but since I grew up in Honolulu, you can see how it happened. Anyway, for anyone who happens to be passing thru there, and wants to check out getting a good fitting pair of contacts, check with Tanco Laboratories. (Getting them may take a couple of weeks; but the last leg can probably be done by mail in a pinch.) I don't guarantee anything, but they can handle some pretty tough cases. There are probably other manufacturing opticians like this, but I don't know of any other names. Donn Terry HP Ft. Collins, Co. ihnp4!hpfcla!donn
mazlack@ernie.BERKELEY.EDU (Lawrence J. &) (12/10/85)
>I've been wearing conventional hard lenses about 18 years (since '67 or >so). Most of that time has been with "fenestrated" lenses (with a hole >in the middle (that fascinates my daughter)). I can wear them all my >waking hours (barring a *really* late night) here in Colorado (where I have also had conventional hard lenses for 16 years (not fenestrated). >The ability to wear hard lenses for extended periods appears to be tied >to the fit: there are the lucky few who get good fits, the less lucky >many who don't, and the *very* lucky (or should I say smart :-) ) who >have found an optician that gets a good fit most every time. I believe >I'm in the last category: there are a small number of (half a dozen?) >opticians who make their own lenses, and have found out how to repeatably >manufacture lenses with a good fit. I deal with one of them (and no, >I don't get a cut for saying this), and I can be assured that if I lose >a contact, I can get a replacement by mail that will fit *exactly* as I also have been getting mine by mail by a guy in Milwaukee. Most all of his clients fit the first time. What is more, he is CHEAP. His name is: O'Jack Miller He has mailed to me all over the US and Europe. >You'll note I said "by mail". The optician is in Honolulu, a bit of a >way from Colorado, but since I grew up in Honolulu, you can see how it >happened. >Anyway, for anyone who happens to be passing thru there, and wants to check >out getting a good fitting pair of contacts, check with Tanco Laboratories. >(Getting them may take a couple of weeks; but the last leg can probably be done Mine also take a couple of weeks. However, I usually have an extra pair (I'm one of those people who REGULARILY loses his lenses - they pop out while skiing or on my motorcycle.) However, as replacement lenses are $15 each, it is no big deal. ...Larry Mazlack