When faced with a one-size-fits-all, sometimes the idea works and other times, causes stress, discomfort, and inconvenience. By contact lenses, not only is this an issue, but the wrong size can end up damaging your vision, resulting in serious vision and eye issues. Contacts rest on the cornea, so getting the right measurements need to be 100% accurate for comfort and health. When the contacts are off in size, this can lead to eye infections or other eye conditions such as corneal abrasion, a painful scratch on the surface of the eye that can make even blinking uncomfortable!
Switching from contacts back to glasses isn't always satisfactory. Therefore, finding an eye doctor for proper contact lens measurements and fitting will ensure you get contact lenses that work for you.
Corneas vary from steep to shallow, and sometimes astigmatisms can cause other variations in shape. Therefore, the eye's cornea needs to be measured correctly, and the exact curvature can be calculated through a keratometer. By simply resting your chin on a support, the instrument takes photographs of your eye in order to analyze reflections of light from your cornea. This will enable the eye doctor to determine the exact curvature of your eye and the size of contact lens that you will need.
If a patent requires a hard-to-fit cornea, based on an unusual curvature of the eye, further computerized measurements are often taken using corneal topography, allowing a more precise picture of the shape of the corneal surface.
Another measurement necessary is by the pupil, the opening at the front of the eye where light enters, and the iris, the colored portion of the eye. Typically, these are measured with a ruler or an automated device.
Your eye doctor may also perform a tear film evaluation in order to assess if you are prone to dry eyes. If you are, your eye doctor may be able to prescribe you specialty lenses that help keep the eye properly hydrated and prevent dry eye symptoms such as red, itchy, uncomfortable eyes.
Once the measurements are complete, your eye doctor often may provide you a pair of trial lenses to put on. After the contacts are in place, a biomicroscope can be used to take a magnified view of the cornea to assess the fit, or see if the eye is being irritated by the contact. Often a number of follow-up visits will be required to monitor the progress of the new contact lenses, until the day arrives when you receive a permanent prescription.
It is important that your lenses be properly fitted to your eyes for maximum comfort and health at all times. For more information, contact your eye doctor today.