CONTACT LENSES

Contact lenses are another alternative to spectacles for correcting refractive errors.  In some cases contact lenses provide better vision than spectacles.  Properly prescribed contact lenses provide excellent vision and comfort; they can also be tinted to change the color of the wearer’s eye.

Whether you are already wearing contact lenses or considering it for the first time, we can guide you to what is best for your sight and eye health.  We routinely manage contact lenses for astigmatism, disposable wear, 1 day disposable, color, bifocal and aphakic lenses for children after cataract surgery.

Many parents are surprised to learn that their child is indeed old enough for contact lenses; the doctor will analyze each case individually and decide on the best form of vision correction.

There are so many different lenses available for a wide variety of needs and preferences; you first need to have an eye examination to determine the most appropriate contact lenses.  Often on the first day you will be taught how to handle your trial disposable contact lenses and once you learn you can leave wearing your new contact lenses.

They must be individually prescribed to ensure that they fit the eyes correctly; poorly fitting lenses can lead to severe eye problems such as infections.  Because contact lenses are placed in direct contact with the eyes they must be cleaned and disinfected regularly, and contact lenses wearers need more frequent eye examinations in order to prevent any problems developing.

There are two main types of contact lenses: soft and rigid.

Soft

Soft contact lenses are most commonly prescribed. They are made of from soft flexible plastics known as hydrogels, which contain water.  The water allows oxygen to pass trough the lens to the eye.  This is important, as the cornea obtains its oxygen supply directly from the air.

These lenses may be worn on a one day, one week, biweekly or monthly replacement schedule depending on the lens type selected for you.  Special toric contact lenses to correct astigmatism can be replaced every three months.

Rigid

Rigid lenses are made of plastics which are less flexible than those used for soft lenses.  The materials used are permeable to oxygen, which is why these lenses are most commonly referred to as rigid gas permeable lenses.  Some of newer materials allow almost as much oxygen to reach the eye as if no lens was being worn.

Rigid lenses provide better vision than soft lenses, as the optics can be better controlled, and are suitable for a wider range of refractive errors.  In some conditions in which the front surface of the eye becomes distorted, such as keratoconus, rigid lenses are the only way of satisfactorily correcting vision.

Rigid lenses require some adaptation on the part of the wearer.  Typically they are less comfortable than soft lenses for the first week of wear, but after that they do not cause any discomfort.  They are more durable than soft lenses, so they do not need to be replaced as often.

Lens care

All lenses have to be cleaned each time they are removed from the eye in order to prevent build up deposits.  The deposits are composed of proteins and lipids from the tears, and if they are not removed they can make the lenses uncomfortable.

There are special lens cleaning solutions provided for different type of lenses.  Contact lenses need to be disinfected to kill any bacteria or other microorganisms which may still adhere to the lenses.  If lenses are not disinfected, the microorganisms can reproduce, and when the lens is worn again the microorganisms will be introduced into the eye.

Prescribing contact lenses is a complicated process.  Contact lenses must not only correct refractive errors, but must also fit without causing any injury to the surface of the eye.  They most move on the surface of the eye and allow the lids to ride over them with each blink, without being uncomfortable.  Professional care and advice is essential.