Andrea wrote:
Hi
I have been doing contact lens trials. I have narrowed down my choice to dailies but am not sure of which brand / size to pick.  My trials range from BC 8.5-8.7 and diameter 14-14.2; the strength is 1.5+.  Before I commit to a year supply, I want to make sure that I am getting the best size and brand combination for my eye (I only need a lens for my right eye).  Shouldn’t I be comparing lens with the same measurements instead of variation in brand, diameter and base curvature? How do I know if the issue is the fit vs. lens brand?  For example, if the Logic 1 day (14, 8.6) feels like a better fit than 1 day Acuvue moist (14.2, 8.5) and Ciba Daily (8.7) should I try the Acuvue and Daily with the same measurements as the Logic before deciding? I find the logic 1 day least noticeable when wearing (14, 8.6). The Ciba Daily (8.7) moves around and has fallen out. The Acuvue moist is comfortable for the first 10 hours.  I won’t be able to see my optometrist for 1 1/2 weeks and only a few trials left.  Hopefully I can get a few more trial lenses before making a decision. Thanks in advance.

ANSWER

Andrea,

Each brand of disposable contact lenses comes in certain parameters.  Basically the lens brand determines the fit as each brand of daily disposable usually only has one base curve and one diameter.  To explain further you cannot try an Acuvue or Ciba daily disposable in the same parameters as the Logic 1 day because they do not exist.  The diameter and base curvature with soft contact lenses, especially daily disposables have little effect on the fit in most cases.  It’s kind of like one size fits all.  An 8.5 vs. 8.6 vs. 8.7 are of negligible difference with this type of lens.  For most people any of these base curves will fit well.  The thing that will determine the comfort is the type of material and the coatings/solution the lenses have been sitting in.  For some people one brand may be more comfortable and for others a different brand may give the best comfort.  As long as your optometrist says that they all fit well on your eye and that your vision is good, it is up to you to decide which one feels the best.  It is quite possible that more than one of them may feel good and give excellent vision.  In that case either one will be a good choice for you.

Dr. Carol Doman

Serdar wrote:
Hi,
I have a question regarding legality. This is my first time I’m buying contact lenses. My opto told me that I need a training period. I did this 2 months ago and I paid $55 for this training since my lenses are customized toric. Then I had to go out of town for about 1.5 months. When I came back and I asked the price of lenses for 6 boxes, they told me a higher number. So, I asked them for my lens prescription in order to get advice from another opto but they didn’t give me my lens prescription. I only have my eyeglasses prescription, which I know little bit different than contact lens prescription. Are they allowed not to give me my prescription? Do I have to buy from that optometrist?
Thanks

ANSWER

Hi Serdar,
Customized toric lenses are a specialized product and do cost more than regular disposable contact lenses.  Generally if the contact lens fitting is completed then the prescription for contact lenses can be released.  However if the fitting was not completed then the contact lens prescription is not released as there is no final prescription.  To have the fitting complete all of the follow up visits must be attended to and the contact lens fit and vision through them need to be satisfactory to the optometrist.  If all of these things were not completed the fit is not finalized.  If you are going to visit another optometrist they are likely going to do a new fitting on you, as they will want to ensure that everything is satisfactory with the contact lenses before you purchase them.  You would just need your glasses prescription in that case.
Dr. Doman

Joebecca wrote:

Hi!
My eye doctor suggested changing from Focus monthly lenses to Acuvue Oasys because of the many hours per day that I wear my lenses and my significant myopia (-11.5). I looked into changing, but my previous base curve of 8.6 doesn`t appear in the options for the Acuvue lenses (they carry only 8.4 and 8.8). I hesitate to go back to the doctor’s office because since moving to Quebec, I`ve been argued with twice for buying contact lenses on the internet (as I`ve done for the past 8 years at least!) Can you help me know what`s best?

Thanks very much,

ANSWER

Dear Joebecca,

It is not a good idea to look for contact lenses, a medical device that can impact your ocular health, sometimes for life, without professional advice and follow-up. There are so many published cases of patients that had a corneal ulcer following a misuse of their contact lenses, bought through internet. Some even after a single use of their lenses. Even if you try to save a few bucks per year by skipping the professional fees related to contact lens prescription and delivery, I think that your eyes worth more than that! Would you buy medication through the internet without consulting a doctor? The answer is obviously no.

When an optometrist prescribes a contact lens, after a proper trial, he takes the full professional responsability. He selects the most appropriate materials to keep a good ocular health in a long term basis. This is why your doctor is right to recommend you an upgrade from Focus to Oasys. It is like coming from a regular rabbit-ear TV to a HD plasma one. These lenses are up-to-date in technology and offer the best protection against UV rays in the market. I recommend strongly this type of contact lens for a regular wearer.

As you saw, there are 2 base curves available in this material. That means that the lens has to be fitted on your eye to alleviate any mechanical problem in the future. This is why I strongly recommend that you see your optometrist again to finalize his prescription.

Ask about the year-supply offered in offices and the manufacturer’s rebate offers that comes with this annual supply. Also ask to have your lenses delivered to your home by Purolator, free of charge, if your optometrist asks the company to do so. In the end, you will pay probably the same amount as with internet but you will have the big plus of being fitted and followed by a competent eye care practitionner. This has no price.

Good luck,
Dr. Langis Michaud, Associate Professor,  U de Montréal

Donna wrote:
I have worn hard contacts and now rigid gas permeable lenses for 30 yrs. with great vision, no discomfort and no change in prescription other than brand. My regular doctor was on vacation when I snapped a lens and needed a replacement. I went to a new doctor. He changed me from Paragon to Boston ES. I found them more comfortable. I returned to my regular doctor. He switched me back to Pargaon, and great discomfort, bloodshot eyes and deposits on contact surfaces within two hours. I asked if he would switch me back to Boston since I had no discomfort with them, but the base curve he prescribed is 41.25 not 8.18 as it was with the comfortable pair of Boston. This seems a big jump in numbers. The Paragon, also at 41.25 were leaving a red rim at the base of my iris–he asked me to try wearing them a little longer each day–and I did. Big mistake. I had intense discomfort even after contacts were out, and my eye started to get gritty all the time.

My question–does this sound like a logical base curve change? Should I get a second opinion on the base curve measurement since the number change seemed unwarranted given the lack of discomfort in the past three sets of BostonES ordered at 8.18? Three weeks without comfortable contacts and counting.

The fill-in doc I went to with the broken lens is no longer there.

ANSWER

Donna,
There are two units used to measure the base curve for contact lenses. One measurement is in dioptres and one measurement is in millimetres. In your case 41.25 is the measurement in dioptres and 8.18 is the measurement in millimetres. The two numbers are the same. You were prescribed the right base curve.

Dr. Doman

Cathy wrote:
I have been wearing contacts for years and never had a problem with Acuvue clear lenses. My prescription is quite high though (-9.50) and I was thinking of trying out Illusions Opaques colour contacts because they seem to be the only brand that carries high prescriptions. The only problem is that the DIA is 13.8 and BC runs in 8.3, 8.6, and 8.9; my current Acuvue Oasys has a BC of 8.4 and a DIA of 14.0 which fits perfectly. I was wondering what would be the best option for me - is it safe to go with the Illusions Opaques with a 8.6 BC?

ANSWER

Cathy,
If you want to switch the type of contact lenses that you are wearing you need to see an optometrist to be fitted with the new brand.  It is not safe to change your contact lens brand on your own.  I would not recommend that you switch to the Illusions Opaques.  There are a few reasons for this.  Number one is that the Illusions Opaques are a conventional contact lens meaning that you would keep for approximately one year as opposed to your current contact lenses, which are disposable.  Conventional contact lenses are very old and let in very minimal amounts of oxygen.  Because you have a high prescription even less oxygen will get in compared to someone with a lower prescription.  Decreased amounts of oxygen put you more at risk for complications from the contact lenses.

Dr. Doman

Adeline wrote:
Hi,

I’ve been wearing Biomedics 38 (monthly disposable) contact lens for over 6 years with no issues.  I just went to an optician and he convinced me to try Mediflex 55, saying it is produced by the same company and is more comfortable due to the higher water content.

I came back and did some research on the Internet but can’t seem to find an answer to my queries.  Hope you can help:

1.  Biomedics 38 means that there is 38% water content and Mediflex 55 means there is 55% water content.  Higher water content means more comfort.  However, I read some articles that say that the water is drawn from the eyes.  This means that Mediflex will draw more water from my eyes.  Doesn’t it mean I’ll get drier eyes with Mediflex 55 and be more uncomfortable?

2.  The base curve of both lens are the same at 8.6.  However, Mediflex has longer diameter at 14.2 while Biomedics is only 14.0.  The optician told me the difference is negligible and only the base curve is important.  Is it true?

Thank you,
Adeline

ANSWER

Hello Adeline,
First, I will address your question about diameter.  The diameter of a contact lens is measured in mm.  This means the difference in size between the two lenses you are considering is 0.2mm.  To the vast majority of patients, this difference is not noticeable when switching.  If you have difficulty inserting your lenses, however or have a small eye-opening, it may take you a few days to get used to the change.
As far as the health benefits of switching between the two above lenses, there really isn’t a large difference between the two.  Although a 55% water-content lens may give you slightly more comfort than a 38% lens, switching from one lens to the other is mostly a lateral move.  Since you have been wearing contact lenses for many years now, I would much more highly recommend a lens made of silicone-hydrogel.  These lenses offer superior comfort and breathability and are a much healthier alternative to either lens above.  There is a silicone hydrogel lens called Harmony available from the same company as you have been considering that is also in an 8.6 base curve.
Whichever lens you decide to try, it is a very good idea to have an assessment by your optometrist to make sure the fit of the new lens is appropriate and that your current contact lens solution will still be compatible with the new lenses.

Hope this helps,
Dr. Donati

Ryan wrote:
Hi,

I have tried for years to wear toric soft contact lenses.  Each and every time I am fitted, I wear the trials for a week and they are great.  I order them and, without fail, about a week into wearing them full-time my right eye becomes more and more sensitive to the point where I have to remove the lens.  Left eye has always been great.

First the lower eyelid becomes sore, then the upper eyelid and eventually the entire eye.  It’s not a sharp, searing pain but more a dull annoyance.  It’s a residual feeling for about a week after I remove it.

Am I lost hope for contacts?  I got a LASIK consultation but apparently my astigmatism of off-centered so the docs wouldn’t touch me.

Thanks in advance,
Ryan

ANSWER

Without examining your eye directly this is difficult to answer.  However, I would suggest that your Optometrist try a rigid lens - a Gas Permeable one.

Dr. Joan Hansen, Optometrist for CAO

Britt wrote:
I have been wearing contact lenses for 14 years with NO PROBLEMS, Acuvue 2 (-4.25) with a base curve of 8.3.  However, on a recent trip to get more contacts they did not carry Acuvue 2, instead I bought O2 Optix by CIBA Vision- but the only base curve they had was 8.6… Could this hurt me by wearing them? How significant is the base curve, and could disregarding it damage my eye?

ANSWER

Britt,

The base curve is the inside radius of the lens and it is necessary to check how it relates to the curve of your contact lens.  The doctor who re-fitted you into the new O2 Optix (Air Optix) lens should have checked the lens on your eye before supplying you with more than one lens.   Having said all of that, the O2 (Air) Optix lens only comes in the one base curve (8.6), and likely it will fit most corneas quite well.  Your eye should be fine with the lens as it actually is a better material than the old Acuvue 2 lens.  If the new lenses are not comfortable or not working as you expect, return to your doctor so that he / she can check them on your eyes.

Dr. Joan Hansen, Optometrist for CAO

Sandy wrote:

I have worn gas permeable contacts for years.  They were bifocal contacts. I have changed to multifocal soft contacts.  It seems my prescription is still changing.  I have worn the soft lenses for 5 weeks.  Each trial pair my Dr. gives me, the vision is improved.  Then 5 days later, they are blurry again.  How long does this happen?  Are my eyes still adjusting?

ANSWER

Hi Sandy,

Sometimes when rigid gas permeable (hard) contacts have been worn for a number of years the corneas can be molded into a different shape.  Once the rigid gas permeable lenses have been removed it can take quite some time for the cornea to return to its natural shape.  On average this usually takes about six weeks to occur, but can vary greatly between individuals.  The more years you have worn rigid contacts the longer it can take for the corneas to stabilize.  In some cases it can take up to three months. What you are experiencing is perfectly normal and hopefully your vision will stabilize shortly.

Dr. Carol Doman