Stabilization Methods for Contact Lenses

Contact lenses come in a wide range of types, able to accommodate many kinds of vision conditions. People with astigmatism or who are nearsighted or farsighted, as well as those with presbyopia (need bifocals), can now wear contacts designed specifically for those conditions. A major issue for the success and comfort of any contact lens wearer is its stabilization on the eye. There are several ways this can be done.

How Stabilization Works

• It's essential to make sure the lens is stable on your eye and does not move around too much through the action of moving your eyes or blinking. Most lenses are manufactured to use gravity to fix this problem; the lens is a bit thicker on the bottom edge to assure stabilization. But there are additional means of stabilization used to meet the needs of different vision conditions. Anyone who plans to wear contacts must see an eye doctor for an eye exam. The doctor will do a number of tests to determine what the correct prescription is needed for your eyes and vision conditions and how to most effectively stabilize them for you.

Stabilization for Astigmatism

• "Fitting Guide for Rigid and Soft Contact Lenses" by Harold Aaron Stein and Bernard J. Slatt provides excellent and clear diagrams and explanations for the methods of stabilizing contact lenses. They explain that patients with astigmatism need a toric lens, which must be manufactured for the specific wearer. Toric lenses use a combination of the shaping the lens--called ballast--to weight it properly and another structural element--called prism--for stabilization. After making a set of measurements of your eyes, and before giving you a permanent prescription, most doctors will have you try out a set of lenses to check the fit, accuracy and comfort.

Care and Cleaning

• Once your lenses are properly fitted and stabilized, your doctor will give you instructions for their daily wear. You should be sure to check how long you can wear the lenses comfortably and whether you need to use wetting drops during the day. In part, this will be determined by how much tearing your eyes produce. Generally, though, all lenses build up protein over time--which can make them uncomfortable as well as less accurate in terms of proper vision--so clean the lenses every night and to change them as directed, if you use replaceable lenses. Additionally, make sure to have regular checkups with your eye doctor. Eyes change with age, and your prescription might need adjusted to ensure proper vision and stabilization over time.