SOFT CONTACT LENSES
Soft contact lenses are the most common type and account for the majority of contact lenses dispensed. These lenses are made of soft plastic polymers and water. They allow oxygen to transfer through the lens material to the cornea, completely covering the tissue, and are very comfortable. The comfort is almost instant and these lenses come in different prescriptions and designs.
HARD CONTACT LENSES
Hard contact lenses are made of polymethyl methacrylate. They do not allow for oxygen transference to the cornea and often cause the tissue to swell. These lenses are rarely prescribed today.
RIGID GAS PERMEABLE LENSES
Rigid Gas Permeable lenses are more pliable, permeable and comfortable than hard contact lenses. A gas permeable lens can transmit more oxygen to the eye than a traditional soft contact lens. In some instances they provide sharper vision than soft contact lenses. They have a greater durability than soft lenses because they do not contain water so proteins and lipids cannot attach to them easily. Gas permeable lenses also come in multifocal designs.
EXTENDED WEAR CONTACT LENSES
Extended wear contact lenses are rigid or soft lenses which can be worn for up to 30 days. While these lenses offer the convenience of sleeping in them at night, wearing them can result in a higher risk of infections, corneal ulcers and inflammations. Frequent followup with the doctor is necessary to ensure compliance and success.
COSMETIC CONTACT LENSES
These soft contact lenses allow most patients to change the color of the iris (the colored part of the eye). They are available in several fashionable colors and can provide a subtle or dramatic change in the eye appearance. They are available for some prescriptions.
TORIC CONTACT LENSES
Toric contact lenses help correct astigmatism. They are available in soft and gas permeable designs. The lenses have more than one power, are multi-curved, and weighted at the bottom for proper centration on the eye. Toric lenses require professional expertise in fitting so additional examination time is needed to achieve successful wear.
MULTIFOCAL CONTACT LENSES
Multifocal contact lenses have more than one power to address different visual needs at distance, intermediate and near. They are available in soft and rigid gas permeable lens designs. These lenses do require additional examination time. Multifocal lenses also require more adaptation time to ensure that activities of daily life are met.