When choosing a base curve for contact lenses, it is important to consider the shape of your cornea and the type of lens you will be using. The base curve of a contact lens is the curvature of the back surface of the lens, measured in millimeters. It is typically between 8.4 and 8.8 mm for soft lenses, and between 6.0 and 8.4 mm for rigid gas-permeable lenses.
To determine the appropriate base curve for your lenses, your optometrist will measure the curvature of your cornea using a device called a keratometer. This measurement, known as the keratometry reading or K-reading, will help the optometrist determine the best fit for your lenses.
In general, a lens with a base curve that is too flat may not provide sufficient coverage of the cornea, which can lead to discomfort and reduced oxygen flow to the eye. On the other hand, a lens with a base curve that is too steep may not conform to the shape of the cornea properly, causing discomfort and poor vision.
The base curve of a contact lens is an important factor to consider when selecting the right lens for your eyes. Your optometrist will be able to help you determine the best base curve for your specific needs.