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Dan wrote:
In the USA, some clinics offer “high definition” glasses. The material used for the glasses apparently provides better vision. The process however starts with an eye examination using a wavefront aberrometer that more accurately maps the irregularities of the eye.

In Canada, optical stores provide these glasses with regular prescriptions. Where in Canada can a person obtain a prescription using a wavefront aberrometer and is the improvement (if any) worth it?

ANSWER

Dan,

I am not aware of any clinic using one, but that does mean there are not any out there.  Frankly I have not heard that the instrumentation is available to a clinic.  If you are aware of the company who distributes the instrumentation, it may be easiest to contact that company and ask where to find one in Canada.

As to the effectiveness of such prescriptions and glasses made from them, in my opinion, the jury is still out.

Dr. Joan Hansen, Optometrist for CAO

Teren wrote:
I am 23 and have been wearing progressive lenses since I was 15. I have multiply eye conditions including a prism and require glasses however I am tired of always having to wear larger glasses to accomidate for the progressive lens as most glasss are not made for younger people needing a prism. At work I use a computer but from a distance and do not use my progressive anyway, what could be the side effects on my eyes if i decide to drop the progressive lens?

ANSWER

Hi Teren,
Progressive lenses are usually prescribed for younger patients to aid with their focus deficiency at near, also you have prisms in your glasses to avoid seeing double.  If you drop the progressive lenses, and depending on how strong your near prescription is, you might notice some difficulty focusing at near.  You can ask your optometrist to trial your reading with just your distance prescription and then go from there.  But for sure worth looking into.

Dr. Sally Aldayeh, OD

Jim Campbell wrote:
I have a question re: progressive lenses.  I have used progressive lenses for many years.  I absolutely love the rx that I got in 2007.  The problem is that my new rx, ie 2009, is a disaster for intermediate vision, ie computer screen work 24 to 30 inches.  Is there a mathematical formula that would dictate when intermediate vision will be impacted.
Here is a comparison of my 2 rxs:
sphere  cylinder        axis
2007    R       -250    -175    93
L       -200    -150    90
read add        225+

2009    R       -275    -175    80
L       -300    -125    93
read add        250+
The new rx was filled at Costco.  I even had the add for reading reduced to +200 but no change.
Many thanks for your help since I am feeling very frustrated by this.
Jim

ANSWER

Hello Jim,
I am sorry to hear that you are having trouble with your glasses.  Looking at your prescription, I notice that there has been a rather large change.  Because your 2007 glasses were so under-corrected for distance (particularly in the left eye), it would have made the intermediate vision seem better.  Also, keep in mind that there are many different types of progressive lenses.  Some are better than others in terms of how much intermediate coverage they offer.  Another option you may wish to consider is an occupational lens.  This is a specific type of progressive lens that offers no distance coverage, but very large intermediate and reading zones.  This type of lens is designed to be worn at your desk only.  You would then switch to your standard progressive glasses for the drive home.
I encourage you to speak to your optometrist of his/her dispensing team.  There you will get a better idea of what type of progressive you are currently using and if switching to a different lens type would suit your needs better.
Best of luck to you,
Dr. Donati

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

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

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

Kevin wrote:
I had worn reading glasses for a few years.  Two years ago I got progressive lenses (trifocal?)  glasses I needed to wear all the time.  After about a month I can say I got use to them and couldn’t do without.  They are polycarbonate lenses with Silhouette rimless frames.  Love them.  Now it time for new ones.  I’d like lenses with better optics then polycabonate and will get rimless frames again. Any recommendations for lenses? OD Sph+1.00, Cyl-.50, Ax090   OS +1.25, -.25, 075

ANSWER

Dear Kevin
Polycarbonate glasses should be as efficient as plastic glasses. With a rimless frame you have no other choice than relying on either one of these 2 type of material. In my opinion, look for the latest generation of designs which are more accurate and easy to adapt compared to the older ones. My favourites are Hoya Lenses.  Other manufacturers (Essilor, Nikon or Rodenstock) are also offering state-of-the art glasses but I did not find easier progressive lenses to adapt to than Hoya Lenses.
Ask your optometrist about them and if this is not as expected, consider a 10 day adaptation period at the most and go back to your provider if a problem remains. My best advice would be to get the glasses from the one who did your exam: no one knows better your eyes than your optometrist.

Good luck
Dr. Langis Michaud, Optométriste, MSc, FAAO (Dipl)
Associate Professor – Université de Montréal

Derry wrote:
I have been wearing progressives for a year. I am quite used to moving my head around to gets things in focus. When I read or do computer work, both eyes do not focus the same. If I get my right eye to totally focus on a word, then try my left eye, the left will be out of focus.  If I get the left eye in focus first, the right eye will be out of focus. I have had the settings checked more than once, and am told that one eye is always going to be more dominant than the other. My thought is that both sides should be equally clear. Could you let me know your thoughts please?

ANSWER

Dear Derry

You are right to expect that 2 eyes work together and with clear and equal focus on each side. There is nothing to do with the dominance of your eyes. That could be related to a misalignment of your progressive lenses, especially if you see that happening just at near. If one of the eye is not well centred with the progressive lens, you can see outside of the clear vision channel, explaining the difference in your vision.

Another possibility is a binocular vision problem, i.e. your convergence is not as accurate on one side compared with the other one. This could be checked through a regular optometric examination, with a special attention to measure the natural deviation (phoria) at far and at near. Finally, you can be affected by a weaker eye that is called amblyopic. This could lead to a difference in vision and if this is the case that would be true either at far and at near.

Having not all the details of your case, my first recommendation would be to get a second opinion in that matter and to ask another optometrist for a more complete examination of your vision and your ocular health, using proper medication to dilate the pupil and to cyclopledge your eyes. This will help to determine the real “refractive error” of your vision and to see if there is any pathology that could explain the difference between the 2 eyes.

Thanks for your interest.

Dr. Langis Michaud, OD, MSc, FAAO
Associate Professor
Université de Montréal, School of Optometry

Beth Ann wrote:
I have just started wearing glasses for the first time. I got two pairs, one for computer I work on a computer 12 hr shifts 4 days on and 4 off. The other are progressive, long story short I am having a difficult time getting use to both and have been back to the optometrist and some adjustments made and asked to try them for a few more days, if this doesn’t work, she is advising digital lens.  I am totally confused as this is my first time ever wearing glasses…  Please help.

ANSWER

Beth Ann,

First time glasses do take some getting used to.  For the computer glasses, you might help your Optometrist by having someone help you measure the distance from your eyes to the computer screen when you are sitting in your “normal” work position.  This will assure that the computer glasses are appropriate.  Progressive lenses can often take a couple of weeks of constant wear to be totally comfortable.   The digital lenses are the newest type of progressive lenses, and may be the answer for you if all else fails.

Dr. Joan Hansen - Optometrist, for CAO

Marilyn wrote:
I am mid 50’s, and have used reading glasses for about 5 years - now at 2.00X magnification. I have recently gotten my first pair of progressives; (they are the distance/intermediate/reading type). The distance and intermediate areas seem as if they will be no problem to adjust to. The bottom reading portion, however, seems almost too narrow to use. I need them for tasks such as starting IV lines and reading fine print, but it seems that no matter how far back I tilt my head, I come to the bottom of the lenses without the item I’m looking at ever coming into focus, and this does not seem to improve with use.
I have to pretty well point my nose at the ceiling to read the computer.
Distance vision is not a problem - might intermediate/reading progressives be something to consider, and are such lenses available?

ANSWER

Dear Marilyn
Yes, there are excellent lens designs available that are specifically suited for intermediate and near use. They are often referred to as office or work-station progressives. In our office, we affectionately nickname them “Dilbert glasses” because they are ideally suited for use in a work station cubicle or a similar small work environment. The top part of the lens is designed to give good vision at a normal computer screen distance, and the lower part of the lens is designed to see detail at a closer working distance. What these lenses sacrifice, however, is clear vision for distance. The top portion of the lens usually provides reasonably clear vision only to a distance of about five to six feet. Beyond that distance, objects appear blurry.
If you are starting IV lines, I presume you are working in an environment where clear vision in the distance would also be important to you. From the description of your difficulties, (clear distance vision but poor near vision) it seems that perhaps the prescription is fitted too low on your face, or that the frame too shallow to accommodate the lens design that you were dispensed. You may need either a deeper frame, a lens design that has a shorter “lens corridor” or a simple adjustment to the glasses. Sometimes a combination of all three can alleviate the difficulties you describe. I think you should bring your glasses back to the place where they were dispensed and explain you difficulties. While it is expected that most patients might have a period of adjustment to their first pair of multifocals, it sounds as if your adaptation may be made easier with some adjustments to the lens design or frame.
I hope this is helpful.
Dr. Smit