Contact Lens Types.
There are a number of different types of contact lenses currently available, each with their own unique features. To avoid confusion we've set out below a brief description of the different kinds, so you're equipped with some basic background information. When you come for your appointment we'll discuss and assess your needs, and together select the most suitable type.
This is a revolutionary new vision correction therapy. The procedure uses specially designed contact lenses that gently correct vision overnight, eliminating the need for contact lenses or glasses during the day. Ortho K brings a modern approach to a technique known as "orthokeratology". Ortho K lenses are manufactured from a special highly oxygen permeable material. When worn during the night these lenses apply a controlled shape to the cornea, reducing or even eliminating shortsightedness. Ortho K is ideal for low/mid- shortsighted people and is a safe, comfortable, semi-permanent form of vision correction without the risks associated with surgery. Our optometrists have undergone extensive Ortho K training to deliver this service.
Hard contact lenses.
These are the original contact lenses, made from a rigid perspex material. Whilst being very durable, these contact lenses do not allow essential oxygen to pass through to the surface of the eye. Hard contact lenses have now been largely replaced by "gas permeable" lenses. Occasionally, they are still used for specialist purposes.
Rigid Gas Permeable (RGP) lenses.
These lenses are made from semi-rigid materials, which allow more oxygen to pass through to the surface of the eye, making them much healthier to wear than hard contact lenses. RGPs only cover part of the cornea. As these contact lenses float on your tears there is some movement whilst blinking, it therefore takes slightly longer to get used them. However once settled they prove to be very comfortable. RGPs are suitable for most prescriptions, but more so for patients who have astigmatism, where they can give better standards of vision. RGPs are easy to handle, clean and very durable.
There are various specialist lenses available for specific eye conditions, for example:
- Hybrid (hard centre, soft skirt) designs
- Semi-scleral lenses
- Increased substance soft lenses
These are the ideal options for conditions like keratoconus and pellucid marginal degeneration.
Soft contact lenses.
Soft contact lenses are made from pliable gel-like materials, which commonly contain between 38% and 75% water, allowing oxygen to pass more freely to the eye. Your tears help maintain the softness and flexibility of the contact lens making them more comfortable to wear. Getting used to soft contact lenses is therefore normally much quicker than with RGPs. Since soft contact lenses contain water, they can become contaminated, and therefore it is essential to follow the correct cleaning and disinfecting procedure.
Disposable contact lenses.
Traditionally, soft lenses have been replaced on an annual basis. Modern consensus is that this is unhealthy and not cost effective. Increasingly sophisticated material technology has led to the development of high quality soft contact lenses designed to be replaced more frequently and that are more and more breathable and obviously more comfortable. The combination of regular replacement and high oxygen transmission makes these contact lenses extremely healthy and comfortable to wear. Disposable contact lenses can be replaced every day, weekly, twice a month or once a month. Currently disposable contact lenses are available for the correction of all common vision correction needs including shortsightedness, longsightedness, astigmatism and the need for reading glasses.
Extended wear contact lenses.
The latest advances in contact lens technology have led to the development of new types of disposable soft contact lens that can be worn overnight, albeit with increased risk which needs to be managed carefully. Some can even been worn continuously for up to 30 days. These contact lenses are made from silicone-hydrogel.
Toric contact lenses.
Toric lenses are specially designed lenses to correct astigmatism. In years gone by they were difficult to measure, design and fit but this is no longer the case and we can opt for RGP, soft or disposable soft toric lenses to achieve exceptional vision.
Multifocal contact lenses.
The baby boomers are now at the age where reading difficulties can be expected. Contrary to popular myth, and many optometrist perceptions, multifocal lenses are highly successful suiting new wearers, those who already wear contact lenses and even those who have no need for any other optical correction. Multifocal contact lenses do not work like varifocal spectacle lenses and therefore give a more natural visual experience.
Contact lenses for children.
Many optometrists and opticians simply will not fit children with lenses. Our experience is that children manage lenses very well, gaining immensely in confidence and outlook. This is especially true if they are playing sport or on stage. We do not put a lower age limit on lens wear, preferring to look at each individual child and family on a case-by-case basis. Our youngest wearers are around 8 years old.
Tinted/coloured contact lenses are now available, which can enhance or change the natural colour of your eyes without affecting what you see. These contact lenses, which are as comfortable as other contact lenses, are available in most prescriptions and in a variety of replacement frequencies.