Silicone Hydrogel Contact Lenses - for the best in Health and Comfort
> The challenges to contact lens wear
In today's modern world, your eyes face many challenges. Long hours at work, air conditioning and pollution can all contribute to dry eye, irritation and discomfort.
These problems are often exacerbated by contact lens wear, which has the potential to disrupt the tear layer, so important for both comfort and optimum vision. Contact lenses that themselves are prone to dehydration act as a further drain on the natural tear film. And discomfort is by far the most common reason for discontinuation of contact lens wear.
A significant proportion of contact lens wearers would like to wear their lenses for the entire day, but until now have not been able to comfortably do so.
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Contact lenses and the oxygen story
The cornea, the clear window at the front of the eye, is a unique tissue. Unlike most body tissues, it has no blood vessels to supply it with nutrients such as oxygen. Instead the cornea absorbs its oxygen directly from the atmosphere. When a contact lens is placed on the eye, some of this oxygen flow is reduced - how much depends on the thickness of the lens and especially the material of which it is made.
A number of complications may arise when the cornea receives too little oxygen, from more serious such as eye infections and red eye reactions, through to general discomfort, irritation and blurred vision.
> Silicone hydrogel - a revolutionary new lens material
The standard soft contact lens material that has served us for many years is rapidly being superseded by an exciting new compound called silicone hydrogel. This new material allows 5 to 6 times more oxygen through to the cornea. The silicone hydrogel material also has a lower proportion of water in the lens compared to conventional materials, meaning these new lenses have a greatly reduced tendency to dry out on the eye.
The main impetus for the development of the silicone hydrogel material was to provide enough oxygen to the cornea for contact lenses to be worn safely overnight when sleeping. But their high oxygen permeability or "breathability" also makes silicone hydrogel lenses an excellent choice for standard daily wear of lenses.
Silicone hydrogel lenses also have coatings that resist and retard lens deposits.
> The benefits of silicone hydrogel lenses
For the contact lens wearer, providing more oxygen to the eye means:
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healthier eyes and especially corneas
- more years of contact lens wear
- less frequent adverse responses to lens wear
- less redness and noticeably whiter eyes
- for some wearers, the option of occasional or regular overnight wear
Reduced lens dehydration results in:
- greater comfort and reduced tiredness, especially towards the end of the day
- improved ability to deal with challenging environments (eg air-conditioning)
- better, more stable vision
Silicone hydrogel lenses mean comfortable, healthy wear for the whole day - no matter how long that day may be.
> Who should wear silicone hydrogel lenses
Our view is that in light of the eye health and other benefits they provide, silicone hydrogel lenses are now generally our lens material of first choice. While not all lenses are yet available in silicone hydrogel, we now recommend that disposable lens wearers currently wearing the traditional lens material change over to silicone hydrogels whenever possible.
You should especially consider changing to silicone hydrogel lenses if you experience:
- End-of-day lens discomfort
- Sore, irritated eyes
- Dry eyes
- Red eyes
- Blurred or fluctuating vision
- Not being able to wear lenses for a full day
> Brands and costs
Silicone hydrogel lenses are currently made by two companies, Bausch & Lomb (B&L)
and Ciba Vision. B&L manufacture the PureVision and PureVision Toric lenses; the Ciba products are O2 Optix and Focus Night & Day.
Silicone lenses typically cost 30-40% more than lenses made of traditional soft lens materials, although considerable savings can be made by purchasing lenses from our online store.
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