Prescription contact lenses are serious medical equipment – certainly not something
that you should take lightly. Perfectly fitting prescription contact lenses, properly
prescribed and supplied can have a hugely positive impact on your vision and on
your life style. Lenses either inaccurately prescribed, that might not fit properly
or lenses supplied using ill-suited materials can cause you no end of problems.
An initial discomfort may be just the beginning leading to inflamed eyes, swelling,
abrasion and infections. In the worst case scenario you may even end up with permanent
eye damage.
The Importance of a Prescription
Contact lens prescriptions are an essential first step in our efforts to provide
you with top quality lenses at unbeatable prices. Without an up-to-date prescription
issued by a qualified eye care practitioner it's impossible to tell whether you
will be wearing the right prescription contact lenses. And it's not just us who
insist on a recent professionally issued prescription. The Government do too – it's
the law! Only by having your eye site properly checked can you be sure that:
(a) you are a suitable candidate for prescription contact lenses
(b) that your ocular health has been expertly assessed
(c) that you receive an accurate prescription
After all, without expert and experienced guidance, how can you be sure they'll
fit? How can you know they're suitable? And who will advise you on proper after
care?
Understanding Your Contact Lens Prescription
Your prescription contact lenses will come with a range of detailed information.
Here's a break down of the typical sort of information you can expect to see on
your contact lens prescription and a brief explanation of exactly what it all means.
Your prescription may look like this:
Right : 8.6/13.8 -2.75 Cibavision Focus Dailies
Left : 8.6/13.8 -3.00 Cibavision Focus Dailies
• Chances are your eyes will not function identically and you
will require a different prescription contact lens for each. 'Right' and 'Left'
is the reference to each eye. You may also see the terms OD and OS. It's Latin.
OD means Ocular Dexter and refers to the right eye. OS stands for Ocular Sinister
and refers to the left eye.
• The first number 8.6 represents the Base Curve or BC (usually
a number between 8.00 and 10.00). It's the shape of the contact lens that your optician
recommends.
• The second number 13.8 refers to the DIA (Diameter). A number
between 13.00 and 15.00 this is the size of lens recommended to fit your eye.
• The number -2.75 is the Power (Sphere). A number between
-20.00 and +20.00 this refers to the strength of your contact lens
• Finally the brand and type - in our example, Cibavision Focus
Dailies.
If you wear Toric lenses you will also see the Cylinder (CYL) in the form of a number
up to -4.00 This indicates the strength of your astigmatism.
Toric lenses also require an Axis representing the location of your astigmatism.
It is represented as a number between 0 and 180.
Bifocal contact lenses will also have the Addpower level between +1.00 and +2.50.
This tells you the reading strength of the lenses.
You may also see information relating to the material used (eg. Oxygen Permeability/Transmissibility
(Dk/L, Dk/t), water content, modulus) as well as thickness.
Prescription contact lenses are too important to take risks with. Don't take chances
with your eyesight. Always make sure you have an up to date prescription, use a
trusted contact lens provider and are wearing the right lenses for you.