Eyes - contact lenses

What are contact lenses?

A contact lens is a synthetic lens that sits on the surface of the eye and helps correct vision problems such as long-sightedness, short-sightedness, presbyopia (the lens is unable to focus) and astigmatism (blurred vision).

Most contact lenses are either:

• Soft lenses – made of a very soft and flexible, water-absorbing material that conforms to the eye shape.
• Hard lenses – made of rigid gas-permeable plastic that cover only part of the cornea.

Soft contact lenses are usually disposable, lasting for one day, 2 weeks or one month.

‘Extended wear’ lenses are also available. These can be worn for 30 days without removal. This may not be suitable for everyone.

Reasons for using contact lenses

People wear contact lenses for various reasons:

• Contact lenses may give better vision than glasses for some vision conditions.
• Some people like the wider field of view given by contact lenses, as side vision is not blocked by spectacle frames.
• Contact lenses do not fog up with changes in temperature or from perspiration, and they are not affected by rain.
• Sports players and people involved in vigorous activities often find contact lenses more convenient than spectacles, especially for water sports and contact sports.

Contact lenses are not always suitable

You might not be able to wear contact lenses if:

• your eyes are drier than normal
• you suffer from allergies
• you have particular illnesses, such as arthritis or diabetes
• you work with chemicals
• you live or work in a dusty environment.

You should discuss with your optometrist or ophthalmologist whether contact lenses are suitable for your vision problem.

Advice about contact lenses

A thorough eye examination and fitting by an experienced professional is essential if you decide you’d like to wear contact lenses.

Regular annual check-ups are important to monitor any changes to your eye health and to update your prescription.

Some people like to wear contact lenses as a novelty costume item (plano lenses) or to change the colour of their eyes without correcting their vision. However, even novelty lenses need to be properly fitted by an experienced professional.

Having an eye examination will make sure you get the proper attention and advice on eye and lens care, and in particular, to avoid any risk of eye infection. Remember, contact lenses are medical devices and you are putting an artificial substance in direct contact with the surface of your eye.

Inserting a contact lens

The general guidelines for inserting contact lenses include:

• Wash your hands and dry them thoroughly.
• Tip the lens from its storage case into your cupped palm.
• Check it for rips or grit.
• Put the lens on your finger, cup-side up.
• Hold your eyelid open.
• Look up.
• Pop the lens onto the white of your eyeball (rigid lenses are usually best placed directly onto the cornea).
• Let go of your eyelid.
• Look down and blink to position the lens over your cornea.

Looking after your contact lenses

Contact lenses should be cleaned and disinfected after each use with a cleaning solution that has been recommended for your type of lens. Poor lens hygiene is one of the common causes of problems with contact lenses and can cause eye infections and permanent damage.

Different lenses need different chemicals. Using the wrong cleaning solution can damage the lens and may cause lasting damage to your eyesight.

Suggestions include:

• Follow your eye care practitioner’s instructions for taking care of your lenses, including the appropriate cleaning solutions and eye care schedule.
• Use only cleaning solutions that have been recommended for your particular type of contact lens. Don’t clean your lenses with tap water, saliva, detergent, soap, household disinfectant or any other solution.
• Wash, rinse and dry your hands thoroughly before handling your lenses.
• Never wear your lenses for longer than the maximum time recommended by your eye care professional.
• Replace your contact lenses as recommended and get them professionally checked if they are bothering you.

Risks of incorrect contact lens use

Incorrect use of contact lenses or lens cleaning agents can lead to:

• inflammation of the eye or lids
• sore, red or watery eyes
• infection and discharge of pus
• slipping or movement of the lens
• dry eyes
• impairment of vision
• allergic reaction.

If you experience any of these problems, remove the lenses immediately and contact your eye care professional.

Tips for contact lens use

Contact lenses are not only small and easy to lose, but delicate and easy to damage.

Remember to:

• Be careful not to pick up your lenses using your fingernails.
• Always make sure your lens is the right way out. Lenses usually 'flare' (turn back at the edges) if they are inside out.
• Insert the right lens first every time, so you don't forget which lens goes into which eye.
• Put the plug in the sink first if you are inserting your contact lenses in the bathroom, in case you drop one.
• Never sleep in your contact lenses unless your optometrist or ophthalmologist has specifically advised that you can do so. Sleeping in the wrong type of lenses can cut off oxygen to your corneas, causing severe inflammation and possible permanent damage.
• Never wear lenses belonging to another person or allow anyone else to wear your lenses.
• Seek advice from your optometrist or ophthalmologist before swimming while wearing your contact lenses.

Watch this Optometry Australia video of tips for contact lens wearers.

Where to get help

• Optometrist
• Ophthalmologist