Contact lenses are a great alternative to wearing eyeglasses. An often unknown fact is that not all patients wear contact lenses as their primary source of vision correction. Each patient is different, with some patients wearing contact lenses only on weekends, special occasions or just for sports. That is the beauty of contact lens wear, the flexibility it gives each individual patient and their lifestyle.
If you decide to opt for contact lens wear, it is very important that the lenses fit properly and comfortably and that you understand contact lens safety and hygiene. A contact lens exam will include both a comprehensive eye exam to check your overall eye health, your general vision prescription and then a contact lens consultation and measurement to determine the proper lens fit.
The Importance of a Comprehensive Eye Exam
Whether or not you have vision problems, it is important to have your eyes checked regularly to ensure they are healthy and that there are no signs of a developing eye condition. A comprehensive eye exam will check the general health of your eyes as well as the quality of your vision. During this exam the eye doctor will determine your prescription for eyeglasses, however this prescription alone is not sufficient for contact lenses. The doctor may also check for any eye health issues that could interfere with the comfort and success of contact lens wear.
The Contact Lens Consultation
The contact lens industry is always developing new innovations to make contacts more comfortable, convenient and accessible. Therefore, one of the initial steps in a contact lens consultation is to discuss with your eye doctor some lifestyle and health considerations that could impact the type of contacts that suit you best.
Some of the options to consider are whether you would prefer daily disposables or monthly disposable lenses, as well as soft versus rigid gas permeable (GP) lenses. If you have any particular eye conditions, such as astigmatism or dry eye syndrome, your eye doctor might have specific recommendations for the right type or brand for your optimal comfort and vision needs.
Now is the time to tell your eye doctor if you would like to consider colored contact lenses as well. If you are over 40 and experience problems seeing small print, for which you need bifocals to see close objects, your eye doctor may recommend multifocal lenses or a combination of multifocal and monovision lenses to correct your unique vision needs.
Contact Lens Fitting in Calgary
One size does not fit all when it comes to contact lenses. Your eye doctor will need to take some measurements to properly fit your contact lenses. Contact lenses that do not fit properly could cause discomfort, blurry vision or even damage the eye. Here are some of the measurements your eye doctor will take for a contact lens fitting:
In order to assure that the fitting curve of the lens properly fits the curve of your eye, your doctor will measure the curvature of the cornea or front surface of the eye. The curvature is measured with an instrument called a keratometer to determine the appropriate curve for your contact lenses. If you have astigmatism, the curvature of your cornea is not perfectly round and therefore a “toric” lens, which is designed specifically for an eye with astigmatism, would be fit to provide the best vision and lens fit. In certain cases your eye doctor may decide to measure your cornea in greater detail with a mapping of the corneal surface called corneal topography.
Pupil or Iris Size
Your eye doctor may measure the size of your pupil or your iris (the colored area of your eye) with an instrument called a biomicroscope or slit lamp or manually with a ruler or card. This measurement is especially important if you are considering specialized lenses such as Gas Permeable (GP) contacts.
Tear Film Evaluation
One of the most common problems affecting contact lens wear is dry eyes. If the lenses are not kept adequately hydrated and moist, they will become uncomfortable and your eyes will feel dry, irritated and itchy. Particularly if you have dry eye syndrome, your doctor will want to make sure that you have a sufficient tear film to keep the lenses moist and comfortable, otherwise, contact lenses may not be a suitable vision option.
A tear film evaluation is performed by the doctor by instilling a diagnostic dye and then viewing your tears with a slit lamp or by administering a Schirmer test which measures tear production. Depending on your results, your eye doctor may recommend certain types of contact lenses that are more successful in maintaining moisture.
Contact Lens Trial and Prescription
After deciding which pair of lenses could work best with your eyes, the eye doctor will have you try on a pair of lenses to evaluate the vision, fit and comfort before finalizing and ordering your lenses. The doctor or assistant would insert the lenses and keep them in for 15-20 minutes before the doctor exams the fit and how it interacts with your eye. After assessing the fit of the lenses, the trial lenses will be dispense to the patient to evaluate with their day-to-day activities to determine if the lens is able to meet their visual demands.
At a follow-up visit, the eye doctor will re-assess the fit characteristics to ensure that they are still fitting properly and that there are no complications with the health of the eye. After a successful trial and assessment, your eye doctor will finalize a prescription for your contact lenses that is independent of your spectacle prescription. The contact lens prescription will feature the specified material along with fit parameters as well as the corrective power appropriate for your visual system. Your eye doctor will also provide care and hygiene instructions including how to insert and remove your lenses, proper storage and care, as well as counseling on your wear schedule.
If you are a contact lenses wearer and start to experience discomfort, redness or dryness in your eyes, schedule a visit with your eye doctor to assess the health of your eyes. After the eyes are healthy, your eye doctor may consider fitting you into a different material, solution or wear schedule to prevent recurrent or further healtlh issues in the future. Our goal is to ensure that you have a lifetime of clear vision to meet your full potential.