Colin wrote:
my eye was exposed to laser radiation. The laser was a 20mW max output at 650 nm. I did not think anything of it at the time. Lately I have been noticing some vision problems. I seem to see faint dots that cause a glossy effect. I saw an optometrist and told him my concern. He preformed his examination and later said he saw no signs of eye diseases. He wrote me a prescription for glasses and sent me on my way. Will my vision get worse or stay the same. Should I see another optometrist or a doctor?

ANSWER

Dear Colin:
I referred your question to Dr. B. R. Chou Associate Professor at the School of Optometry at the University of Waterloo. He has done much work in the area of environmental and occupational eye safety and has had some involvement in the problems of laser flashing of drivers and pilots. Here is his response.

“Colin’s information indicates he was most likely exposed to a Class 3B laser. These are continuous output lasers of less than 0.5 W output emitting at a wavelength between 315 nm and 2500 nm. Exposure is potentially hazardous if intrabeam viewing occurs as in Colin’s situation, but the duration of the exposure is the key element. Without knowing how long his eye was exposed to the laser, it’s not possible to determine whether he was at risk of an eye injury. However, the fact that the optometrist detected no changes at the retina suggests that no clinically visible damage occurred. It is possible that there is some sub-clinical effect that gives rise to the visual phenomenon he reports, but our best available detection methods likely won’t be able to find any evidence of damage. I don’t know if his vision will get worse as a result of the laser exposure, but it is most likely that there will be no permanent effect resulting from this incident.”

I hope this is helpful.
Dr. Smit

Karen wrote:
I’m in my early 50’s and obviously because of my age, I started needing “readers”. A year ago, I finally got a prescription for glasses that I wear as needed. I have astigmatism in my left eye and extremely good distant vision in my right eye. Six months ago, I got a job where I use a computer almost all day so I got a prescription for bi-focal computer glasses that allowed me to see the screen clearly and read paperwork when I looked down.  Approximately 3 weeks ago, I had bad allergies so I spent the day in bed reading. After a few hours of reading (with my prescription glasses), I looked outside and everything was blurry.  It was almost like my eyes deteriorated overnight. My distance vision is now blurry and things that I could read, like a clock a few feet from me, are also blurry. My eyes haven’t recovered and I’m afraid I’ve damaged them. Help!

ANSWER

Hello Karen,
First of all, don’t worry!  It is impossible to damage your eyes by simply using them.  What you may be suffering from is accommodative spasm.  This is similar to pulling a muscle after a long run (especially if your glasses happen to be a little weak).  Another possibility that we must consider here is diabetes.  Sometimes sudden changes in blood sugar can cause a sudden and often drastic change in your vision.  Either way I think it’s a good idea to make an appointment with your optometrist.  He/she will be able to help with the blurry vision.  Also, if it’s been a while since your last physical exam, it may be a good time to visit your family Dr. as well.
Dr. Donati

Larry wrote:

I am looking for safety glasses for work and have a prescription for bifocals. One store I visited said they will not give me progressive lenses in a pair of safety glasses. Why?

ANSWER

Bifocals (the lined type) and progressive addition lenses (invisible bifocals) are available and common in safety glasses, however, without knowing details, the optical may have refused to provide the progressives if the client was trying them for the first time.

Many first time progressive wearers require a period of adaptation to the effects of the lenses, and are routinely cautioned about the potential for difficulty with common activities. Peripheral distortion, image swim and the necessity of “finding your feet” are all cited as possible effects of the lenses.

The dispenser may increase his liability if he knowingly dispenses progressive safety lenses into already hazardous situations.

Steve wrote:

Is it possible to see 3D without using those cheap disposable glasses with red and blue cellophane plastic lenses?

I first noticed this effect about 7 years ago with the purchase of a new 17 inch CRT computer monitor.

It seems when I visit a web site that uses an all black background with bright fire engine red text and deep navy blue text on the screen and I’m sitting more then about 500mm back from my computer monitor (19 inch LCD at home these days) the red text appears to be about 12mm in front of the blue text.

I notice this effect at my place of employment too which also uses software with an all black background. It’s interesting to note that the software at my employer uses an all black background with multiple colors. These other colors seem to sit in a depth somewhere behind the red text and in front of the blue text. I’ve not dwelled much into this but I think the depth of the colors might follow the colors of a rainbow?

This used to be a bit annoying years ago but I guess I’ve learned to live with it. Is there a name for this condition?

I am in good health, age 47, not on any medication, and have never taken any strikes to the head. I do wear glasses with mild corrective lenses to see far away.

Thanks

ANSWER

Steve,

This is an interesting question in fact. Many thanks to bring it on this forum.

The condition is called chromatic aberrations.  This refers to the dispersion of a point of color as seen by our visual system. When many colors are superposed these aberrations can overlap and a 3D effect could appear.

By nature each color is defined by a wavelength, specific to its components. Red are considered longer wavelengths and blue-purple are considered shor waveleghts colors. This is why reds are seen anterior (in front) of blue or black colors having shorter waveleenghts.

It is not considered appropriate (visually speaking) to use software with a black background and coloured letters. You can surely adjust your screen to be on a white or grey background (which is preferable) with black letters. The contrast will be better and you will alleviate chromatic aberrations you actually experience.

If you use filters like in 3D glasses, the 3D effect will be reduced by elimination of the colour that is opposite to the colour of the filter. The red filter will eliminate green letters by making them black (on a black background these letters will disappear). Same thing for the green filter that will eliminate the red prints. Therefore one eye is seeing some letters, the other other letters. Considering that you see at this moment one eye at the time, you eliminate 3D effect but you also affect your binocular vision which can create discomfort over time.

This is why I recommend to modify your screen and background to come back to a more natural environment (black and white)

Hoping that this will help.

Langis Michaud
Associate Professor - U of Montreal

I have worked with laser beams with no eye protection and now my eyes hurt. What can I do?

Stefan

ANSWER

Dear Stefan,

This is a difficult question to answer without knowing what type of laser you were working with, in what capacity and for how long. The most significant damage incurred from working with lasers normally occurs in the retina and although it can have a significant effect on vision, it is not usually painful. You do not mention any loss of vision, hence it would seem that you have not suffered any significant damage to your retina.

However, if you are experiencing symptoms of sore eyes, it would probably be wise to undergo a thorough examination by your optometrist to determine if an underlying cause can be determined. Make sure you mention your concerns about your exposure to laser radiation. Also, I hope you are now wearing adequate protection if you continue to work with lasers.

Dr. Henry Smit

I work in a pizza restaurant and now in about two months my eyes are very sensitive the heat oven. The pizza oven bothers me. I went to an optometrist and another one. They tell me your eyes are ok but somethink is wrong. I work now 6 years in the same oven  and i was ok. They told me I have dry eyes not to much tears and maybe caused from the heat of the oven. Tthe aircondicioner it hurts the same. Is there anything you can help me with any solution?  thanks, luan

ANSWER:
Dear Luan, Thank you for your interest in this question. You are working in what is called a “challenging” environment. This can alter the tear film function on the surface of the eye and could contribute to create dryness which seems to be your problem. A recent study, published in a major journal in ophthalmology, proved that wearing silicone hydrogel contact lenses, namely the OASYS lenses (Johnson & Johson) could help to restore the comfort and to alleviate the dryness occuring in challenging environments. Other lenses can also offer a solution to this problem.
 
Another way to address this issue is to control the environment conditions if possible. If it is not possible, to put non-preserved artificial tears in your eyes, hourly or each 2 hours, could prevent the eye surface to dry. I strongly recommend Refresh Tears (Allergan) or Blink (AMO) for this use. Do not ever put Visine or other over the counter products that promotes to relief for red eyes since they can cause rebound effect over time.
 
If the condition is not solved either way (contact lenses or lubricants) you can consult your optometrist and asking him to consider punctal plugs as a treatment. This procedure helps the eye to remain wet but could have the disadvantage to create tearing in other conditions (outside, at home); therefore, it has to be considered a last solution.
 
Good luck and thanks again for your interest.  
Dr Langis Michaud, o.d. M.Sc. FAAO (Dipl)
Associate Professor University of Montreal - School of Optometry

Hello, I was recently diagnosed with high pressure in my eyes. I meet an optamologist in approx. 3 weeks. My main concern at this time is my job. I have worked under microscopes for almost 20 years. For the last little while ( 1-2 years) I have complained that my eyes were sore. Now over a period of 8 hours/5 days a week it seems to get worse. I’am also a Type II diabetic. Will this type of work and eye strain accelerate this condition ? It is hard to find answers anywhere about this. Should I consider changing professions ?
Thank YOU, Bruce Sparks

ANSWER:
Bruce, To give a complete answer would require more data from your file. For example, do you wear glasses ? For far distance? For near distance?
Diabetes type II can influence the vision either at far and near distance. Your optometrist/ophthalmologist will dilate the pupil to find out if there is any trouble with the retina which is the ocular structure the most affected secondary to diabetes.
Glaucoma and high pressure in the eye should be differiencated. High pressure is a known risk factor to develop glaucoma but it is not automatically linked to this disease. If present, glaucoma does not alter the vision except at a late stage. It would be surprising that you are at this point actually.
Your best course may be to consult your ophthalmologist and if there is no need for medical treatment see your family optometrist for regular follow-ups (at least each 6 months) and to address any visual disturbance you may encounter. Good luck.
Dr Langis Michaud, OD.MSc FAAO (Dipl)
Associate Professor, U of Montreal