Contact Lenses

Contact lenses offer an amazing alternative to spectacles, particularly to those with stronger prescriptions. Sporting people find them especially useful due to a larger field of view that is completely free of frames.

Trial fittings of contact lenses are easily performed to assess your suitability. The practice is equipped with corneal topographers to give highly accurate measurements of corneal curvature – critical for contact lens fittings and vital for keratoconus and orthokeratology patients and others who require rigid gas permeable (RGP) lenses.

Soft disposable lenses are now available in a wide range of lens powers and even colours to suit a greater range of prescriptions and lens wear modalities.

Most optical prescriptions can now be corrected with contact lenses. Some patients notice sharper focus with spectacles, while some find contacts achieve a better result.

Can I buy contact lenses over the counter?

Contact lenses can not be purchased over the counter. They need to be fitted and then prescribed by the optometrist to ensure the correct fitting, comfort and safety of the optical device on the eye.

What is involved before I can purchase contact lenses?

The following steps are involved and are explained below:

1. General consultation:
   This allows the optometrist to check the prescription and the health of the eyes to make certain that the eyes are suitable for contact lenses. The optometrist will discuss the different types of lenses available to suit your prescription and lifestyle.
2. Fitting:
   The fitting involves having trial contact lenses placed on the eye to check for correct fit, comfort and good vision.
3. Teach and Delivery:
   Once a lens type is determined, the teach and delivery appointment is to instruct the patient how to insert and removal lenses safely; go through and show the patient how to look after their lenses and give advice about the DOs and DON’Ts with contact lens wear.
4. Aftercare Visits:
   At the aftercare visits the optometrist will check the lens fit, comfort, and vision and make sure that the lenses are not causing any changes to the eye. These visits are usually scheduled at 1 to 2 weeks, 1 month, 3 months, 6 months and then 12 months after. It is important that the eyes are examined annually for any changes to the eye health with contact lens wear; earlier if extended wear contact lenses have been prescribed. Usually after the first aftercare if everything is OK, you can then purchase your supply of contact lenses.

What are the different types of contact lenses?

Soft Conventional Lenses:

These lenses are designed to be worn daily but can be kept for up to a period of 12-18 months. This type of lens would suit a person who has a complicated prescription and requires a custom made lens. Conventional lenses require a little more maintenance than the disposable lenses to ensure the longevity of the lenses.
This type of lens is not as commonly used these days due to the availability of soft disposable lenses.

Soft disposable lenses:

Daily disposable contact lenses are designed to be used once only and then disposed of which makes it low maintenance and hygienic.

2 weekly disposable lenses can be worn on a daily basis for up to 14 wears and then disposed of making it more cost effective than a daily disposable. A multipurpose cleaning solution is required for maintenance.

Monthly disposable lenses can be worn on a daily basis for up to 30 wears and then disposed of. Maintenance is the same as for a 2 weekly disposable.

Extended Wear contact lenses have been designed to be worn on an overnight basis as it provides more oxygen to the eye than the standard disposable lens. The lens is safe to be slept in for up to 30 nights and days. Extended wear provides the wearer with convenience and less maintenance and handling of the lenses.
These lenses are not suitable for all patients.

Can I sleep in my lenses?

Most disposable lenses are not designed to be slept in. Sleeping in the lenses can lead to complications on awakening. There are two lenses on the market that provide higher oxygen to the eye and have been designed for the purpose of extended wear. Ciba Vision Focus Night and Day and Bausch and Lomb Purevision are the only two lenses that can be slept in for up to 30 nights and day. Regular visits to the optometrist are required to ensure that the eye health is not compromised due the extended wear of these lenses.
(For more information, check out the following websites Ciba Vision at www.cibavision.com and Bausch and Lomb at www.bausch.com.au )

What is new in soft disposable lenses?

The latest in soft lenses is the new silicone hydrogel lenses from Johnson and Johnson (J&J) – Acuvue Advance and Ciba Vision – O2Optix. These lenses are made from a similar material to the Ciba Focus Night and Day and the Bausch & Lomb Purevision. They have been designed for patients who like to wear their lenses all day everyday. These lenses are not designed to be slept in but due to the high oxygen and more hydrated lens this allows the eyes to breathe better and provides better comfort than the standard disposable lenses which make it safer to wear for long hours. Check out J&J and Ciba Vision’s website for more information about these new lenses. (J&J at www.j&jvision.com and Ciba Vision at www.cibavision.com )

What if I have astigmatism, can I wear contact lenses?

These days the companies have catered for a greater range of prescriptions, even for those with astigmatism. Disposable lenses can now fit more astigmats due to the expansion of power range. Not all patients with astigmatism will be suited to soft disposables but it is best to book an appointment to discuss your options with the optometrist.

For those who want to explore the possibility of being able to sleep in their lenses and have astigmatism, Bausch and Lomb have released a high oxygen lens called Purevision Toric, made from the same material as Purevision. Purevision Toric provides stability and superior vision with the added benefit of extended wear option. (For more information, check out Bausch and Lomb’s website www.bausch.com.au )

Hard or Rigid Gas Permeable Lenses (RGP)

Gas Permeable lenses are made of a more rigid material than the soft lenses. This type of lens suits most prescriptions and sometimes provides more superior vision in some patients than soft lenses can.

Patients with keratoconus, or those who have had corneal grafts can sometimes benefit from RGP lenses which can provide better vision than soft lenses or even glasses.

Other uses for RGP lenses include orthokeratology.

So what is Orthokeratology?

Orthokeratology (or Ortho-K) is the use of a specially designed contact lens to remove or reduce myopia (short-sightedness). It will usually remove totally up to 3 to 4 dioptres of myopia but this depends on different shape factors of the cornea – determined by a corneal topographer. Ortho-K does not have a permanent effect and it requires the use of a retainer lens, worn overnight. The lens is removed in the morning to allow good vision during the day.

OrthoK only works for myopia at this stage. Long sightedness is not able to be controlled by present technology but researchers at the University of NSW are working on this.

Ortho-K offers an alternative to glasses or contact lenses where these would be perhaps problematic during the day. For example, for sport, especially water sports or people working in dusty areas or with other occupational requirements.

Why not just have laser surgery? Laser surgery has a permanent effect which has obvious advantages but if an unwanted complication occurs that reduces your vision that effect may also be permanent. Because Ortho-K is an ongoing procedure it can be modified if your eye changes whereas laser surgery only corrects your vision as it is at the time. Ortho-K is also much less expensive than laser surgery.

A recent study from Hong Kong has also found that on average orthokeratology halves the rate short-sightedness progresses in children. Potentially, this has huge advantages in the long term particularly bearing in mind some of the complications of high levels of myopia.Check out the sites of some of the leading companies in contact lens designs:

Ciba Vision at www.cibavision.com.au
Bausch & Lomb at www.bausch.com.au
Johnson & Johnson at www.j&jvision.com
Cooper Vision Hydron at www.coopervision.com
Gelflex Laboratories at www.gelflex.com
Menicon at www.menicon.com
Ultravision Capricornia at www.ultravision.com.au