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Contacts are Feeling Dry and Sticky
Tina wrote:
I have astigmatism in both eyes. I have been wearing contacts for 22 years with no problems till now (RGP for 20 years & non-breathable toric soft lenses the last 2 years) I recently took a job working outdoors, I have always worked indoors, & started having allergy symptoms & problems with my contacts: drying out, itching, & having what is best described as almost a sticky type feeling. I talked to my physician who put me on a daily dose of Claritin for my allergies which has helped but I am still having the issues with my contacts. I am also having to use rewetting drops & eye drops for contacts to help with keeping them feel moist. I never had any problems like this when I wore the RGP's but I have never worked outside either. My annual exam is in 1 week & am going to be purchasing new contacts but was wondering with me having astigmatism, problems with outside allergies, & working outside what would be a better choice for me? Stay in the toric soft lenses but get the breathable ones or go back to Rigid Gas Permeable lenses?
Dr Henry Smit's response:
Hi Tina
Your question is a tough one to answer without the benefit of examining your eyes and the fit of your current contact lenses, so I will do my best to answer your question in general terms with the information you have provided. Based on your history of having worn contact lenses for 22 years, I am guessing that you are over forty years of age.
There are currently several very breathable and “moisture retaining” toric soft lens designs available that provide most wearers with clear and comfortable vision. If you suffer from allergies, however, the resulting changes to your tear film and ocular surfaces may make your lenses less clear and comfortable. Fortunately, there are prescription eye drops available from your optometrist that can provide effective relief of allergic eye symptoms in most cases. These drops need to be applied once or twice a day, either after the lenses are removed for the day or at least an hour before the lenses are inserted. Additionally, our eyes tend to become less moist as we mature. You may still need to use lens wetting drops as well, but these can be applied while the lenses are worn.
If you wore RGP lenses fairly consistently over a twenty year period it is likely that the lenses, because of their rigidity, induced a temporary change in the curvature of your cornea during that course of time. This change in curvature has likely mostly reversed itself after two years of wearing soft contact lenses, so there is a reasonable chance if you simply reorder your old RGP lens design, your lenses may not fit the same way as they did originally. Whether you choose to go back to RGP lenses or move to more permeable (breathable) soft toric lenses, you will probably need to undergo a refitting process to ensure that the lenses fit properly to maintain the health of your eyes and provide you with clear, comfortable vision. Either permeable soft toric lenses or rigid gas permeable lenses could work in your situation but without the benefit of a firsthand assessment of your eyes, I am unable to recommend one option over the other.
Hope this is somewhat helpful.
Dr. Smit
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Patient Wants the Base Curve for Contact Prescription
Thida wrote:
Hi, I read somewhere on your website about the rules concerning the optometrist giving out the prescription to his clients. I understand that if someone did not get an eye exam for his/her contacts and/or there was no proper follow up, then the optometrist cannot give the client the prescription because of health safety concerns. However, in my case, I had my eye exams for my contact lenses and I paid for the exam. I even bought contact lenses from them for a while now. Everything is ok and the follow up too. I just never thought of asking for my prescription until today when I wanted to buy my contacts somewhere else because it is cheaper. The receptionist would give me the number for my POWER, but not the number for my BC. How come? He said that if I want to buy them somewhere else, then I need to get my eye exam for my contacts at that place. This does not make sense to me. He also added that it was the Ontario law concerning eye care and optometry. Can you please enlighten me on this? Thank you Thida
Dr Joan Hansen's response:
Thida, It is my understanding that the information on your records is yours and that we are obligated to give you that information. We need to keep the original file, but you are entitled to a synopsis of the information or a copy of the entire file. Ask you doctor directly.
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Halos Around Lights While Wearing Contacts
Ahmed wrote:
Hi, I recently acquired contacts and because of that have been especially critical of my vision. I notice that I had rainbow colored halos around bright lights when looking directly at them. Ive done some research and after a quick look from the optometrist there was nothing visibly wrong with my eyes. I am myopic (.75 and 1.25) but my glasses are overcorrected 1.75 both eyes. I don't wear them usually because I don't like the idea of a higher than needed prescription although I see fine and have headaches over my right eye once in a blue moon, with nausea. I notice the halos only at night around bright led type light or street lamps when looking directly at them. No glare or starbursts just halos, only noticeable if I try to see them, otherwise my night vision is unaffected. I'm worried because I'm going to apply for policing and this may stop from being an officer. My acuity has been at 20/40 for almost 9 years and my prescription and pretty much stayed the same. I'm considering LASIK and I'm wondering if this may be the answer for the halos, since my Google searches seem to say LASIK fixes myopia. I may be wrong or have read wrong I otherwise have no ailments conditions or diseases and no other signs I'm 20 years old. Halos don’t bother me and I can drive fine at night. I'm just wondering why I'm experiencing this. It may have also been there all along just haven’t noticed it.
Dr Henry Smit's response:
Dear Ahmed:
Thank you for your multi-pronged inquiry. I will do my best to answer your questions based on the information you have provided.
Halos around lights are most often caused by defects in the optical system of the eye – primarily the cornea and the crystalline lens. In the case of a person who wears contact lenses, the contact lenses become part of the optical system of the eye, and they too can contribute to the phenomenon of seeing halos. Sometimes it takes only a subtle defect in the clarity or surface quality of any of the contributing elements of the eye’s optical system to cause the wearer to see halos around lights. These defects can sometimes be difficult to discern in a “quick look” at the eyes.
It is also possible that the contact lenses are causing a bit of edema (swelling) of the corneas. If you are wearing the contact lenses for long hours, and if the halos are only visible when you wear the contact lenses or shortly after they are removed, this may be the underlying cause. Corneal edema is more likely to happen in cases where the contact lens is fitting too tightly, or if the contact lens material does not transmit sufficient oxygen to the cornea.
Wearing glasses that over correct your myopia causes the eyes to do unnecessary extra focusing in order to maintain clear vision. This is probably the underlying cause of the discomfort you experience when you wear them. I would suggest that you update the prescription in your glasses so that you will have a properly prescribed alternative to your contact lenses should you happen to find yourself in situations where wearing your contact lenses is not feasible.
A personally customized LASIK procedure may be able to reduce your halos if they are being caused by what are referred to as “higher order aberrations” in your eye’s optical system. In custom LASIK procedures, the laser treatment that is applied is completely tailored to your specific prescription and any unique optical aberrations that your eyes may have. While there is no guarantee that all halos will be eliminated, custom LASIK may be beneficial in some cases. The procedure should also reduce your dependence on glasses or contacts.
In any case, seeing faint halos around lights is usually not considered an impediment to joining a police force. So long as your corrected and uncorrected visual acuity and other measureable visual skills (such as colour vision, binocular coordination and peripheral sensitivity) meet the standards established by the police force you wish to join, and your eyes are disease free, then the faint halos that you have described should not prevent you from pursuing your chosen career.
Best of luck.
Dr. Smit
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