Nine common contact lens questions answered

I wrote for a couple of years on eyecare on Quora now. Some contact lens questions come up time and again. I hope I can help more understand it better. Here are some commons one, some are answered by me, some are answered by other helpful Optometrists.

• What’s more attractive, wearing glasses or contact lenses?

Everyone can look attractive in glasses and contacts lenses. It depends on if you pick the right pair of glasses that fit your prescription, your facial shape and your style. It’s best to have a trained professional to help pick the right one so you get the advantage of fashion and function. If you need to perform on stage or in sports, sometimes the contact lenses provided the added convenience of not risking your glasses falling off and losing your vision during performance.

• Which contact lens is better for astigmatism? J&J or cooper or B&L or Alcon?

You aren’t going to like this answer, but here goes. Contact lenses must be fit by a qualified, licensed eye care practitioner. This person takes careful measurements and determines through the fitting process which contact lens is better for you as an individual. To say that one FDA approved CL is better than another is really not the question. The question is “which brand provides a better fit and an optimum visual/physical solution for your particular eyes?” Leave this decision to your qualified practitioner. This is not like saying which underwear do you prefer Hanes or Fruit of the Loom? Each pair of eyes is unique and the right selection of CL’s for you may not be the correct choice for the next person., OD from SUNY. 

•  What age can I start wearing contact lenses?

I have patients that is as young as 5 years old wearing contacts. Some doctors have them at infancy before cataract surgery. In these cases, a family member may help remove, insert and clean the lenses. For children to independently clean, insert and remove their lenses, age 6 or 7 is a good start. The Optometrist would train them in office to do it properly to do it safely. It’s not advised to learn it on your own. There is also the option of daily disposables to reduce washing. They need to do only insertion and removal. Works great for teenagers.

•  Is it possible for the contacts to travel from the eye to the nose through the sinuses?

No, the lining of the eye limits it from happening. The opening to the nose is very small. It would allow tears to drain, but not contact lenses. 
 

• Can you lose contact lenses in the back of your eyes?
  No, same as above, the lining of the eye limits it from happening. It doesn’t travel that far back. 

 

• Is the rx the same for -3.00 or -3.25? 

We use to say that when powers are under -4.00 diopters there is no need to adjust for vertex distance. However this is not always true. We do an over refraction to check for binocular visual acuity. Everyone’s eye reacts different with the lens to create a tear lens as well. It needs to be assessed individually, especially for sports performance. 
 

• Is wearing coloured contact lenses as comfortable and reliable as normal contact lenses? What's the difference? Are colored contact lenses safe?

There is more colour pigment on the contact lenses, so there are less oxygen going through the lens to allow the eyes to breathe. If done properly with a licensed practitioner such as an Optometrist, and monitored yearly, it can be done very safely.
  

• Does oxygen permeability decrease over time with monthly silicone hydrogel contact lenses? I would like to know if I should change to Dailies as I have some neovascularization.

wowowow SILHY soft lenses generally don't cause neo-vascularization. 
Neo-vascularization happens when the eye has low or lack of oxygen for an extended period of time. It could be minimized if the eyes are monitored by the Optometrist frequently. 
Changing the dailies may not help the problem. It’s best to see the Optometrist to find out what’s the real cause behind it and change it, or fit new lens if needed be. 
 
 

• Is sleeping in contact lenses cause harm to eyes?

The cornea receives the bulk of it’s oxygen from the atmosphere. When the lids are closed during sleep far less Oxygen gets to the eye. A contact lens will deprive the cornea of Oxygen in the open and closed eye state but with the added challenge of the closed eye many problems can results.
The Centers for Disease Control and Prevention (CDC) warns that sleeping with your contacts in makes you six to eight times more likely to suffer from a corneal infection. Infections in the eye can be uncomfortable, and they can also cause permanent vision loss. 

Dr. Yan Ling Liang 
Markham Optometrist
www.wardenoptometry.ca 
905-940-2015 
Changing lives one eye at a time!