3D & Bowing Effects

[cmknrb]

I am 21 and have been wearing contacts for about 9 years.  During that time, I have not had a backup set of glasses to wear when my contacts are out.  I finally got sick of not being able to see at night because I am pretty "blind", at least in my opinion.  My current contact prescription is -4.75 on both eyes.  I recently went to the optometrist to get glasses.  I also asked for a prescription for my contacts so that I can buy those when I need more because I can still see well out of my current contacts and still have a few boxes.  The new prescription for my glasses were R -6.00, L -6.00.  PD is 29, 32.  The frames are chose are pretty narrow.  The new contact prescription was -5.25 for both eyes.  I really don't know what this all means so I hope this is enough information.  Anyway, I can't really wear these glasses.  They give me an instant headache and make me feel nauseated.  When I wear them, it looks like everything is kind of 3D and things bow in.  For example, when I look at a straight horizontal line, like where the ceiling meets the wall, it bows down at me.  When I look ahead, straight vertical lines to my sides bow inward like this (  ).  Also, when I look around, everything seems pretty jumpy.  I went back to my eye doctor and they checked my glasses and the prescription was what he measured.  So he redid my exam and said the prescription was a bit too strong and that is what was giving me the 3D and bowing effects.  Everything looked OK when I was looking throught the machine when he found my prescription, but I can't look around at thingsthrough it, just straight ahead.  So, when I got my glasses back (through mail b/c I am a college student living away from home where my eye doctor is) they were slightly better, but still not good.  I don't even want to wear them.  I haven't got new contacts because, as I said, I still have some and I can see fine.  So I wonder what is wrong, why are my glasses doing this?  Could it be the frames I chose, or that the prescription is still too strong?  If the prescription is still too strong, when looking through the machine, how can I tell the difference between right, and too strong?  What can I say to my doctor to help him diagnose the problem?  Should I try a different doctor?  Please help, I really would like to be able to wear my glasses.  Thanx so much.

[John C Hagan III, MD, FACS, FAAO]

You will have gone overnight without your contacts so your eyes hopefully are 'back in shape'  Have them do the refraction. The machine is called a phoropter. When they have the test complete. Ask them to put your prescription in TRIAL FRAME and let you wear it for 10-15 minutes to see what you think.

A trial frame is a frame that is adjustable and can be made to fit any face. It has little clips in it that hold "trial lens" they can put the prescription in front of each eye so you can see what it feels like.

JCH III MD

[cmknrb]

I do have one more question.  When I go back to the optometrist to get my prescription checked, I need to know the difference between the right prescription and one that is too strong.  When looking through the machine, everything looks good and clear, but I can't move and look around through it like I can when I get my glasses to make sure everything looks OK.  So when I am at his office, how can I tell between the correct prescription and one that is too strong?

[John C Hagan III, MD, FACS, FAAO]

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[cmknrb]

Thank you for your help.  I will make another appointment with my optometrist to get my prescription checked again and I will make sure I have someone to drive me so that I don't have to put my contacts in.

[John C Hagan]

Many people find it a problem to get glasses that work well for them while they are wearing contacts. This is more of a problem with rigid gas permeable contacts RGP than soft CTL but it can occur with both. This is called spectacle blur and is caused by the contacts changing the shape of the cornea. when the contact is taken out the eye is bent out of shape and starts to change back to the natural shape. As this happens it changes the glasses prescription. This can take anywhere from a few minutes to reshape to as long as many months.

So I believe your problem is spectable blur. Nevertheless there should not be as much difference between your glasses RX and your contact RX. I suspect your glasses are too strong. The bending you describe is typical of astigmatism, your glasses and contacts don't have a astigmatism correction on them so the contact must be warping your cornea and causing it.

There is no good solution for this. What we usually do is have a patient come in first thing in the morning and not put their contact lens in when they get up. that way the cornea usually has a 8-12 hours rest to reshape itself. We refract the eye being careful not to make it too strong "over minus".

While the glasses won't be as good as the contacts we can tell the patient that the longer they have the contacts out the clearer the glasses will be, if you had your glasses test immediately after taking the contacts out the longer you have them out the more blurred the glasses will be.

JCH III MD

[cmknrb]

Sorry, I now realize you asked for the prescription he gave me when I went back.  He didn't give me a copy of the new prescription for it, I can call and find out, but he said the first one was only slightly stronger.

[cmknrb]

I wear soft contacts and I wear them the whole time I am awake, so all but about 7-10 hours a day.  They are disposable and I change them once a month.  The glasses prescription is R -6.00, L -6.00.  PD is 29, 32.  This is the only prescription for glasses I have had in about 9 years.  I wonder if it is still too strong because I can still see well out of my -4.75 contacts and the new prescription of -5.25 seem a lot higher, but I am not sure if that is really a big difference because I don't know anything about what these numbers mean.

[John C Hagan III, MD, FACS, FAAO]

Do you wear soft contacts lens or gas permeable?
Do you wear them as extended wear (24 hr/day) or daytime only?
What is the new glasses RX?
Are the contacts disposable? Do you change them at specified period?

JCH III MD