Tina wrote:
Hello,

I started wearing glasses for reading/computer work about 12 years ago, but I could go without glasses the rest of the time. I’ve always had a really weak prescription, but with astigmatism. Then a year ago, I started getting headaches and my Dr. explained that I might need to wear my glasses all the time. So I started doing that, but cannot ever go without my glasses without getting headaches/blurred vision.

Then tonight, suddenly, I had blurry vision with my glasses on and better vision with them off. About 20 minutes later, I find I need them for the computer in a lit room, but not in a dark room, and that I need them to read the spines of books about 12 feet away, but not for my television (which I always need).

Is it possible that I only need them for reading again? It may be important to note that I have fibromyalgia and have always expected given that the disease attacks the muscles, that it might be related.

I’ll make an appointment with my optometrist, but any insight would be appreciated.

Thank you!

ANSWER

Dear Tina
You do need to see your optometrist. Rapid fluctuations in vision such as you are describing are not normal and are most commonly associated with systemic health conditions. Your fibromyalgia might certainly be a factor, but the possible existence of other conditions such as diabetes needs to be investigated.
Best of luck
Dr. Smit

Breen wrote:
I am a myopic mid-50s adult with extremely good peripheral vision.  As a result, I am very sensitive to distortion of any form (the barrel effect), and am aware at all times of the edges of my glasses, even though they are attached to the bridge and temples only. I also have a second pair of single vision glasses with a field of focus optimized for computer use. Progressive lenses are out of the question.

My previous single vision glasses were Nikon high refractive index lenses (Nikon 5, with RI 1.74), and I was very happy with the level of distortion, which while always present, was tolerable.

My new prescription (OD/OS -3.25 spherical only, 0 cyl.) resulted in an opportunity for me to try out the Nikon SeeMax lenses, which promise minimal distortion.  However, the result is exactly opposite from what I expected, and exhibit far more curvature distortion than my old lenses.  My previous prescription was OS/OD -2.25 spherical, which is a significant difference.  However, when I look at the details on the new glasses receipt, I see they used the 1.6, and not the higher 1.74 (or even 1.67) refractive index lenses. This was a surprise to me, as I assumed that they would order the same RI as the old ones, and I will be getting them to replace them with the thinner 1.74 lenses to minimize the visibility of the edges of the lenses (due to extremely good peripheral vision).

Could I expect less curvature distortion with the higher refractive index of 1.74, vs. the 1.6 that I’m unhappy with?

What if anything, does the base curve have to do with distortion, and how is this related to the refractive index for the lenses in question?

Also, are there other lenses which might be more suitable for me than the Nikon SeeMax to minimize peripheral distortion?

ANSWER

Dear Breen
From your letter it appears that you are a very “sensitive observer” – someone who notices distortions that the average person would not detect. The barrel effect that you mention tends to be more noticeable with an increase in the size of the lens that you are looking through. If there is more peripheral lens to look through, you will be exposed to more peripheral distortion. Although you did not mention lens size in your letter, if your new lenses are larger than your old pair, it may be a factor in the distortion you are experiencing.
Typically, as the index of the lens increases, there is an increase in the amount of radial astigmatism (another form of distortion) in the lenses. However, the customized lens surfacing techniques such as those used with the Nikon SeeMax have typically made great improvements in reducing the level of the other lens distortions (such as barrel distortion) experienced by the wearer. However, a -3.25 lens will induce more barrel astigmatism than an equivalent sized -2.25 lens made of the same material. A 1.74 index lens at -2.25D would be flatter and thinner than a 1.6 index lens at -3.25D and this difference, in your case, may also be contributing to the distortion you are noticing.
The Nikon SeeMax is a well designed lens with a good track record. There are other lens options from different manufacturers that also perform well. Unfortunately, there is very little reliable independent data available that compares lens performance from different manufacturers. Most of the information available is self-generated by the lens manufacturers, and to no one’s surprise, each manufacturer appears to claim that their own lens performs best. Hard data aside, the other factor that the lens manufacturers cannot control is the visual perception of the patient wearing the lenses. It has been my experience that patients with same the very similar lens prescription, visual demands and frame size still express different preferences in their lens design choices. Based on your apparent sensitivity to distortion, it may be advisable to stick with a frame and lens design that you have successfully worn in the past.
Boring, but it sometimes does the trick when all else fails!
Dr. Smit

Marsha wrote:
I am 43 and have amblyopia. Despite patching & surgery as a child my sight in my “bad” eye is 20/200. I find when I read I get eye strain in my bad eye. My good eye is not quite ready for reading glasses - I find I am tending to look under my glasses to read but 1.0 reading glasses are too strong.

What can I do for the eye strain? Would patching the bad eye help when I’m reading?

Thanks,
Marsha

ANSWER

Dear Marsha
When a person enters their “forties” they usually become aware that they are losing their ability to focus their eyes for near tasks such as reading. Based on the fact that you look under your glasses to read it would appear that you are slightly myopic (nearsighted). If you are in fact nearsighted, as I assume you are, you do not need to focus as strenuously to see things up close when you take off your glasses, or look under them as you are doing. Wearing a pair of +1.00 readers makes your eyes focus even less, and coupled with the benefits of taking off your distance glasses, this may result in an over-correction for your close vision. You might try reading without your glasses and no reading glasses to see if that makes you more comfortable. If it does not, you should consult your optometrist for a thorough assessment to determine what prescription would be most suitable for your needs. I would not recommend patching the bad eye.

Hope this helps.
Dr. Henry Smit

Mike wrote:
Hi,

I recently had my prescription updated and went to get a new pair of glasses but ran into some visual distortion issues.

My normal optometrist (that I have been seeing since I was 10, I am 27 now) was not available at the time, so I made use of the in-house one where I was getting my glasses.

The prescription [I don't have it] (which was later checked by my normal optometrist) was accurate, save for the prism. For whatever reason, She could not see it while taking the measurements. So she added the prism from my glasses that I was wearing at the time (a 1 B0 prism).

The optician did the glasses. When I tried them I noticed a significant distortion of the ground immediately in front of me, it was like I was walking up a 3′ hill all the time. This was looking ahead normally while walking. It was also like they were magnifying the image as well, as if I looked straight down, my body/legs appeared to be about 2′ tall (I’m 6′). I made a point of wearing them for a few days to see if it was an adaptation issue but there was not noticeable improvement.

At that point I went back to the opticians and they rechecked everything PD, prescription, as well as positioning of the frames on my face to no avail. They suggested that I go to my normal optometrist to double check the prescription. Which I did and ended up with:

OD -800 -075 175 1.5 B0
OS -650 -050 008 1.5 B0

I took this back to the opticians and they re-did the lenses with the new prism. These were a no go as well. Same visual distortion. Again, they checked the lenses, position etc. All seemed ok. Though they noted that the base curve of the new lenses was not the same as my old ones. So they suggested that they re-grind the lenses with the old base curve to see if that would fix the situation.

While it did improve the distortion it was no longer a 3′ hill immediately in front of me, there was still a significant rise in the ground probably from 6 to 10′ away, I would have to guess that it looked like it was about 1′-2′ rise, though it was smooth not abrupt, kinda like a pronounced crown in the road.

At that point I had given up on the glasses as the opticians could not provide any answers or other things to try, other then to check the prescription with my optometrist again. Which I did and ended up with the most recent prescription of:

OD -775 -075 175 1.5 B0
OS -675 -050 006 1.5 B0

I have not had this made into a set of glasses yet, as I don’t know what was causing the problem and I am a little leery of going through this again considering the cost of the lenses alone usually runs about $300+.

The lenses they were using above were Zeiss 1.67 RI, their lab was using Essilor Kappa. The frame size was 49-19, Oakley Rotor S.

My old glasses (which I am still wearing) were from Lensecrafters, the lenses are Featherweights (polycarb 1.54 RI?). Frame size 46-18, similar lens shape to the Oakleys, rounded rectangle. Old glasses prescription is:

OD -750 -050 180 1.0 B0
OS -625 -050 180 1.0 B0

Any ideas what was happening?

Thanks for your time.

ANSWER

Mike
Dear Mike
I will do my best to offer some suggestions based on the information that you have given me. For starters, yours is a fairly high prescription, and high prescriptions create more distortions than lenses made in a lower prescription. Secondly, I suspect that you are a sensitive observer and that you may be bothered by induced distortions that might otherwise go unnoticed by the average observer.
It appears that your new prescription is a little bit stronger, that you are wearing a slightly larger frame, that the amount of “base in” prism has increased slightly and that the axis of the astigmatism has changed slightly (going from exactly horizontal to being tipped up slightly at the outside of the frame). Each of these changes, by themselves, would probably not cause a great change in visual perception. However, these four small changes, in combination, may be enough for a sensitive observer to notice. In addition, it is possible that the “wrap” of the new frame is different that the vertical centration of the lenses may be different from what you are used to wearing. These factors could make your adaption to the new glasses a little more difficult.
Fortunately, most patients do eventually adapt to changes in prescription and lens design. If you have worn the glasses for a period of a few weeks and do not experience any improvement in your symptoms, you may want to try to go back to a smaller frame. As a last resort, you may also want to go back to the polycarbonate lenses, but any improvement in spatial perception you might gain may also be offset by the generally lower optical quality that polycarbonate lenses provide away from their optical centers.
I wish you luck. It sounds that you and your different care providers are doing their best to make things work for you. Hopefully with a little more perseverance you will be successful.
Best of luck
Dr. Smit

Adam wrote:
I have a student who is not able to read the board from the centre of the room.  I asked if he had been prescribed glasses, and he said yes, but that his parents told him he couldn’t wear them on a regular basis and so he had to sit in the front.  His parents told me that they didn’t want their son wearing the glasses regularly in class because their natualpathic optometrist told them that his vision would get worse if he wore them and better if he didn’t wear them.

My understanding is that this is a myth based on a change in perception, but I’ve also heard of other people being told this by their optometrists.  Is there any credible evidence for this stance?

Thank you.

ANSWER

Adam,

Thank you for your question.  First, it is difficult to answer since we don’t know all the real facts, but perhaps you could share some of this information with the family in question.  I also must say I have never heard of a natualpathic optometrist.

You are correct about the myth. Not wearing his glasses will not slow progression of myopia (near sightedness). There is no natural way to alleviate the development of myopia.

If choices have to be made, since school is important to a child’s development, I would suggest that this child choose the classroom to wear his glasses. He could easily take them off to walk to and from school, while playing outside, while doing sports, and while at home. Squinting and struggling to see often results in headaches and may hinder his education.

Children grow until they are in their mid 20s and during this growth phase, the eyeball will grow and cause myopia to increase. We have not found a way to stop this growth as yet. Many studies have been done on ways to reduce myopia, and you can read about them on this website: www.allaboutvision.com/parents/myopia.htm

Ruby wrote:
Hi. I am far-sighted and have add +2.25DS.  I’m currently using 2 eyeglasses: 1 bifocal for reading and 1 with full grade lens for computer use. I use the computer almost the whole day at work. Problem is, I switch from one eyeglass to another when I have to get up from my desk because with the computer glasses, everything is blurred beyond an arm’s length. My optician has recommended progressive. But would this solve my problem, can I use the progressive for computer work?  I understand it’s the lower part of the lens that I would need for computer-distance.  Would that not strain my neck as I would have to tilt my head to use that part?  I’m supposed to buy the glasses in 2 days, so I would appreciate your advice. Thanks.

ANSWER

Hi Ruby,
Progressives would solve your problem as they actually have three different powers – distance, intermediate and near.  All distances will be clear with these lenses.  There is a different prescription for the computer than there is for reading.  With progressive lenses the top part of the lens is for distance, and then it gradually changes into an intermediate prescription and then into reading at the bottom of the lens.  The intermediate portion is part way down the lens.  Therefore to look at the computer screen you will have to look slightly down, but not all the way to the bottom of the lens.  You do need your computer monitor in the right position for progressive lenses to work optimally.  Ideally you want the top of the monitor to be at about eye level, that way you are naturally looking down at the monitor.  If your monitor is too high you will be forced to tilt your head up.  The only thing you may notice in going from a strict computer lens to progressives is that the clear area will be narrower and in one spot, versus the computer lenses, which allow clear vision for the computer through any part of the lens.
Dr. Doman

Iva wrote:
Hello
My name is Iva and I’m writing to you because I’m concerned about my brother’s lazy eye. He is only 17. By lazy eye, I mean that his eye looks like Paris Hilton eye.
It has only been 2 years that he’s been wearing glasses. When we went to the doctor he told us that the number on the other eye was rising (from 0.3 to 0.5). He prescribed two medicines, Betoptic and another one. He told us that when my brother is 21 years old, he can have surgery. His vision on the right eye (the lazy one) now with the glasses is only 60%.
Please, I have so many questions…
Can the surgery wait until he is 21 years old?
What can we do now to protect the other eye?
Thank you for your time!

ANSWER

Iva,

It sounds like a few different issues.  The lazy eye, which you say looks like a Paris Hilton eye, I think, means that his eye is turning out.  This is generally caused by a problem with the eye muscles and can sometimes develop if the vision in that eye is significantly decreased.  The fact that the eye is turning out is mainly a cosmetic issue. Having surgery to straighten the eye muscles, will unfortunately not improve the vision in that eye.  Therefore waiting to have surgery to straighten the eye will not cause any further damage.  By the other information you have given me it sounds like he has glaucoma.  The numbers you gave (0.3-0.5) would be used to describe the optic nerves in the back of the eye.  This number represents the shape of the optic nerve. I am a little confused, but I think you mean that this number is changing in his good eye?  The medication they have prescribed is an anti-glaucoma medication. This will decrease the pressure inside the eye, which should stop the optic nerve numbers from changing. This will help to protect the good eye.  I understand that it can be very worrisome when someone in your family has serious eye problems.  Hopefully my answers have helped somewhat.

Dr. Doman

Rob wrote:
Hi,
I’m 46 and my doctor has strongly suggested I go with progressive lenses.  The last 4 years I have been wearing reading glasses which are now fine for computer work but not so good for reading fine print up close.

The first pair of progressives I could not even leave the office with as the reading area at the bottom of the lense was literally just that. I had to go all the way to the bottom of the lense where I could actually see the frame in my line of sight and the words still were not clear.

My doctor gave me a second exam, with a different prescription and then a second pair of progressives, which I did take out of the office.  These were Zeiss progressive lenses, supposedly the best on the market.  The top portion was for distance and the bottom portion for reading.  The reading area was indeed correct.

The problem was that 70% of my work is in front of computer screens, and I have to look at information (numbers, meter levels, images) in many different places at the same time so I use my peripheral quite a bit.  The intermediate area of the progressive literally only had 1 inch that was in focus so I could not see any of this important detail in my peripheral at all.  My calculation is that the top portion of the lense (distance) was need 5% of the time – the middle portion (1 inch in focus) was needed 70% of the time and the reading portion 25% of the time.

So this is where I am now.  Do I go with a progressive with intermediate (computer in focus) at the top and reading at the bottom?  Do I go with regular bifocals with intermediate as main portion and reading at the bottom?  I want as much peripheral in that intermediate potion as possible – as it is needed for the work I do.  I don’t care about people seeing the line, my priority is being able to do my work.

Problem:  I have to pay for this next change of lense so I have to get this right.

Thanks

ANSWER

Rob,

I get this type of question quite frequently and understand your frustration.  Computer progressives (intermediate at the top of the lens and reading at the bottom) will be a good option for you.  These give a wider intermediate portion than a regular progressive.  However, the regular bifocals for intermediate and reading will give you the widest intermediate portion.  With the regular bifocals, because there is a line, the top part will be exactly the same as your current reading glasses.  The computer progressives will have some distortion in the periphery of the lens, but it will be less than regular progressives. I hope this will help you make your decision.

Dr. Doman

Caitlin wrote:
I wear contacts 95% of the time and I recently had my yearly check up. I found my vision less clear lately with my contacts, but my prescription hadn’t changed (-1.50 in both eyes). However, now when wearing my contacts, the left one is clearly not as sharp as the right. I’ve tried putting a new contact in, switching the contact, but nothing seems to help. It’s so annoying that I eventually give up after an hour and have to put my glasses on. What could be causing this? The obvious answer is that my left eye needs a stronger prescription, but my check up was only a month ago, and there was no change.

ANSWER

Caitlin,
Is your vision perfect with your glasses?  I would recommend returning to your optometrist to have them check this problem. Of course I haven’t examined your eyes, so it’s extremely hard to give you an answer, but I’ll give you some possibilities.  It’s possible if your glasses are perfect that you may have a small amount of astigmatism that your contact lenses are not correcting for and your glasses are.  A lot of times if there is a small amount of astigmatism it can be compensated for with regular contacts.  However if the astigmatism gets to a certain point, it will affect the vision and then a contact lens to correct astigmatism, called a toric contact lens may be required.  Astigmatism happens when the very front of your eye, the cornea is not perfectly spherical like a ball, but shaped more like a football. There are two different curvatures that need to be corrected, instead of only one.  Otherwise there could be an issue with your cornea or eyelid causing the problem.  Sometimes inflammation can develop in the cornea or eyelid, which will affect the quality of vision.  The main thing is to go back to your optometrist to make sure there is not an eye health issue which is causing your symptoms.

Dr. Doman

Sandra wrote:
How often should retinal imaging be done (annually, bi-annually) and at what age should it start?

ANSWER

Hi Sandra,
Retinal imaging can be done at any age.  Eye diseases are more common as we age, but can occur at anytime.  Generally it is recommended that adults have their eyes examined every 1-2 years.  The frequency depends on your history and risk factors for the possible development of eye disease. Your optometrist can advise you on what would be best for you.
Dr. Doman