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Scott wrote:
I have myopia and wear my single vision glasses 'morning to night' to enhance my vision. Part of my employment has me working in industrial settings where protective eyewear is required. In these instances I have resorted to using OTG (Over the glasses) safety eyewear but find them to be bulky and uncomfortable overtop of my regular eyewear. I have looked at prescription safety eyewear but have not purchased a pair because of their cost and my concerns over their durability in the workplace. On a side-note, I generally go through 4-8 pairs of OTG safety eyeglasses in a given year due to scratches rendering them unusable. So, I was wondering if "Reader Safety Glasses" might be a cost-effective solution to my quandary. I see them advertised by safety product suppliers but am not clear on what and/or who they are for. Please advise.
Canadian Association of Optometrists's response:
Hi Scott, and thank you for your question.
While so-called “drug store” readers have been available for some time, they are a fairly recent addition to the safety glasses catalogue.
Readers are designed to provide simple magnification to those of us that require extra help seeing up close. This usually occurs as we age, with the onset of a condition known as Presbyopia. Readers do provide a cost effective solution to a very common problem, however unless you have perfect vision otherwise, they do have limitations.
These types of lenses can only provide equal magnification for both eyes, and do not correct for common vision problems, such as astigmatism. Most potential users experience some form of refractive error that cannot be addressed by this type of correction.
Another concern is that these lenses are “self prescribed”, and may help mask an underlying undiagnosed condition that is the cause of the vision problem. Always consult your eye care professional before choosing any type of corrective eyewear.
I agree that OTG glasses are a poor choice, but I would contend that prescription safety glasses are a great investment in terms of comfort, visual performance and, most importantly, protection. The application of a premium scratch coating on the lens, along with proper care and cleaning, will give them durability in all but the harshest environments.
Your employer may have a program in place to help with the cost.
When choosing safety glasses or any other type of personal protection equipment, always look for the appropriate safety certification mark, either from the Canadian Standards Association, or from the American National Standards Institute.
Doug Dean
Director, Occupational Vision Plan
Canadian Association of Optometrists
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Re: Eye Exposed to Laser Radiation
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?
Dr Henry Smit's response:
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
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Re: Vision Problems After Allergy Attack
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!
Dr. Virginia Donati's response:
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
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