RGP fit (tight vs. loose)

Sorry to keep bugging the group with my RGP's, but things seem fairly
slow anyway.

My RGP fit, in my non-professional opinion, is on the loose side. When
I blink they go up, then slide back down and hang low. If I turn my
head to the side, they slide toward the ground. I expressed my concern
to my eye doc on the follow-up check after getting the lenses, but he
thought I should keep them this way. His rationale, as best I can
understand, is that he didn't want to make them too tight because of
possible irritation where the edges touch the eye.

My vision is great in these lenses, except that I have quite a bit of
eye watering at times, which makes vision worse. At some times of the
day, I also get fogginess from dryness (fixable with drops). Also,
when the lenses ride low, I get effects like light reflecting off the
top of the lenses when going under overhead lights.

I'm trying to decide if I should wait this out a little longer, or if I
should go back and ask _again_ whether these should be tightened up.
What do the group experts think are the pros and cons of tight vs.
loose fitting RGP lenses? Do you guys agree that there are patients
who are better off with low sagging lenses? Is there irritation
associated with the lenses sliding around that could be contributing to
my watery eye problem?

--

 

Not a problem.

Sometimes, but not always, a low riding lens is indicative of a tighter
fit. There's certainly nothing wrong in wanting a comfortable fit and
a stable retinal image.

"WHEN" the lenses ride low, meaning sometimes they don't? Sometimes,
too much tearing can cause a lens to ride low. You mentioned dryness,
which suggests the mechanism whereby the eye becomes dry, the dryness
triggers corneal irritation, which triggers an episode of tearing,
which in turn causes the lens to ride low.

Again, it isn't clear that the lenses are too loose. But, there are
more options these days, including larger intralimbal lenses that can
facilitate centration, and corneascleral lenses, i.e. Macrolenses that
always stay centered, no matter what. If you were my patient, I would
expect you to come back in this situation.

DrG

 

If you were my patient, I'd suggest a pair of simple spectacles, and, with
a bit of luck, not having to come back for a while. Of course you would
not be my patient, as I am not a Dr..

 

They almost always move towards low. They move somewhat slowly, so if
I blink often, they keep moving back up and the effect isn't as
pronounced. Towards the end of the day my eyes seem more dry and the
lens are more likely to stick between blinks. I just put them in this
morning and looked right away. They are riding a little low, but not
as low as after wearing a while. They also stay in place sometimes.

On one occasion I noticed a lens sticking a little high, so I get the
impression that the lenses move high when I blink, then start moving
down. Where they stop seems to depend on how "watery" my eye is at the
time.

Thanks for the info. I'll probably schedule another visit. I hate
being the problem patient. I already moved on from my last eye doc
because I started getting a feeling of "eyes rolling" when I walked in
for repeated visits. Is RGP a specialized enough area that I ought to
seek out an expert if I want to be picky and really nail this? I see
so much promise for great vision with these if I could just solve these
few little issues.


--

 

One old technique for getting a lens to stay in place is to have it
stay tucked up under the upper eyelid. It may be that your upper lid
may actually be catching the upper edge of the lens, and then forcing
it down when you blink. As well, you may be only partially blinking,
which then never allows the upper lid to "capture" the lens and pull it
back up.

Sounds like you should see an expert, although I'm not versed in how
you go about finding one. : )

DrG

 

No, he wouldn't be your patient because you preach
Zenni's and not wasting all that money on doctors at
all -- since their sole purpose is to take your money
right? Just some cheap experimentation on your own
should take care of anything for half the price. Besides
contacts are just a vanity item like those name brand
frames and stuff. I'm sure glad your here to add balance
to the group Dicky.

-Quick

 

What diameter are your lenses? If they aren't sufficiently large, they
will give blur on blinking and side glances. Use a 10 or 10.5mm lens
and this will get rid of the edge awareness of your vision.

Also, the general rule is fitting large and flat (loose) but sometimes
it can help to tighten the lens up a bit. There will be no ocular
discomfort from going a little tighter, the edges are polished and will
not cut into your eye.


dr grant

 

Apparently you have some anti-contact agenda. Too bad, since aside
from my few complaints, my vision hasn't been this good in 10-15 years.
And, incidentally, the whites of my eyes have never been whiter.

--

 

Hard to say for sure, but it looks to me like my eyelid pulls it up,
then it slides back down. When my eye first opens, it's up.

Where are you located? I travel for business sometimes...

--

 

I don't know. I don't know if it's universally this way, but no doc
I've been too has ever volunteered my prescription. I always have to
ask. I haven't yet asked for my full contact Rx, although I do know
the power numbers.

Anyway, I did ask my doc about going larger and he though it was a bad
idea because they were hanging low, and thus the bottom edge of the
contact would be into the white area of the eye. When I first got them
I felt like I saw the edges in all different directions. For whatever
reason, I now only notice the top edge when they are sagging.

What I was told was that tight lenses cause long term "wear" at the top
and bottom edges. Sounds like you don't necessarily agree?



--

 

Dick is just one big agenda.

Sorry if I missed this, but what were you wearing before? Glasses?
Soft contact lenses??

RGP lenses have a *very* high Dk rating (oxygen transmissibility). The
last time I tried a pair--though it didn't work for me--all the
redness disappeared from my eyes, too.

Incidentally, the ones I tried *were* the intra-limbals mentioned
above, and I *have* known a few people who were *quite* happy with
Macrolenses.

The scleral might be shooting a mouse with an elephant gun in your
case. I really don't know....

 

Just glasses before. I tried torics a little but never had any luck
getting consistent good vision.

It's pretty amazing really. I had glasses before and chronic slightly
red eyes. Maybe it's just the extra tearing induced by the lenses or
something?

What's the down side of these other types vs. the run of the mill?
Just cost?



--

 

A lens that is too steep/tight can "lock" on the
cornea and cause lens adhesion which aint
good. There are various fitting strategies
that can work equally well- I try to get
an upper lid fit (sup edge tucked under
the lid) for best comfort for most
patients.

frank

 

http://www.copfameye.com

DrG

 

Charles replied:

Here's where I bow out to the docs for real answers.

From my limited knowledge, there's not much downside to the
intra-limbals:

http://www.lensdynamics.com/Irregular Corneals/Dyna Z Intra-Limbal.htm

OR: http://tinyurl.com/zqo8e

or the MacroLens:

http://www.chcontacts.com/macrolens.asp

http://www.chcontacts.com/article.asp?title=machist

http://www.chcontacts.com/article.asp?title=macconcpt

[I don't like their site particularly. Difficult to find ready info,
IMO]

The "however" is: it's quite possible that there are larger diameters
available for the lens you are wearing ... if that turns out to be the
issue (rather than fit or design).

Again ... above my pay grade ;-)

Doc's? If you would??

[scuse me]

 

You have some options there.

1. If you want to stick with RGP contacts, try a different size and
base curve. A scaral lens would stay put but its so huge its scary to
put in your eye!
2. Go back to glasses. This might not be easy if your pescription is
high with lots of astigmastim due to spectacle minification and
disortion
3. If you are totally fed up with RGP contacts and really hate glasses,
theres laser surgury. Its not without risks and trade-offs. You will
NOT see anywhere as well as you do with RGPs and probably not even as
well with glasses. But itll greatly improve your uncorrected vision and
should give you vision good enough to function. Great if you arent too
picky about perfect vision and just want to ditch those irritating
contacts/glasses.

 

Charles,

Fair warning: Ace woke up in a meadow some years ago ... after a
tremendous binge on hallucinogenic mushrooms ... and now seems to
think he's an optometrist.

Be afraid.

Be very afraid.

 

LOL silly doctor Brooks! I wish I were one, but I am not a doctor.

 

Don't worry, I read ace's posts for amusement purposes only.

--

 

Ace, you need to go and do something useful in society. We know
you're a bit odd.. probably got Aspergers like half those on usenet
but still there must be something you can do. Quit sitting at home
and surfing the internet.