Contact Lens Types

Contact lenses can be divided into two main types.

Rigid Gas Permeable Lenses

These are small ‘hard’ lenses which give a good standard of vision and are relatively durable and easy to look after. They typically have a life expectancy of twelve months if  properly cared for. Gas Permeable lenses allow oxygen to pass through them and help the eye to ‘breathe’ better than any other lens type, but initially some people may find  adapting to them takes a little longer. They are the most suitable type of lens for high prescriptions and for children.

Soft  Lenses

These have a ‘jelly-like’ appearance and feel. The standard of vision varies according to your prescription. For some individuals a special type of soft lens (called a Toric lens) is needed to correct Astigmatism.

Soft lenses allow oxygen to pass through them to help the eye ‘breathe’. They are very comfortable, but they have a shorter life span. In the past it was recommended that soft  lenses be replaced every year. Nowadays, frequent replacement lenses are readily available reducing the complications of infections. Indeed there are even lenses which  are worn once only and then thrown away thus removing the need to clean and store the lenses. This saves both your time, and the cost of solutions.

Special types of soft lens are available which can change the colour of your eyes. This is possible whether you have light or dark coloured eyes and there are a number of  attractive colours from which you can choose. There are also ‘Crazy’ lenses which will give your eyes an unusual appearance e.g. Cat’s eyes or Dartboards.

As one becomes older, the eye no longer focuses so well close up. Spectacle wearers use bi-focal or varifocal lenses to overcome reading difficulties. For contact lens  wearers, one answer is to use reading spectacles over the contact lenses when needed. Another possibility is to have ‘bi-focal’ contact lenses. These allow the eyes to  focus over a greater range of distances, but they do not always give sufficient clarity for people with very precise visual needs. On occasions we can use a technique called  monovision. This means giving one eye clear distance focus and the other eye clear near focus. It can be extremely effective although not everyone can tolerate it.

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The subject of hygiene is probably the most important aspect of contact lens wear. Hands must always be washed before handling the lenses or touching your eye. Lenses  should always be cleaned (except daily disposables) in accordance with instructions issued by your optometrist and only with the recommended fluids.

Maximum wearing times will be advised by your optometrist. These should be strictly adhered to because over-wearing your lenses puts the eye under stress and can leave it more susceptible to infection.

Lens Replacement

At this practice we believe that it is in the best interests of the health of the eyes to replace contact lenses at regular intervals, in accordance with current expert opinion,  certainly at least once a year. No matter how thoroughly you may think you are cleaning your lenses, they never come completely clean. Over time the surface of the lens  deteriorates, this is due to a number of factors including scratches and stubborn deposits. As a result:-

  • The lens becomes less transparent so your vision is not as clear.
  • The deposits on the lens can irritate your eyes and eyelids so the lens is not as comfortable. In some cases this irritation can become so bad that you would have to cease wearing lenses completely.
  • The lens does not allow so much Oxygen to pass through to the eye. As a result the eye is at much greater risk of side effects and complications.

This is why we recommend schemes where your lenses are replaced at specified intervals. These schemes also include as many check-ups as are considered clinically necessary,  including a full eye examination once a year. The cost of your care products (cleaning/storing solutions) is included where appropriate. Typically there is an initial  payment followed by monthly payments by Banker’s Order. In addition, membership of the schemes entitles you to a discount off any complete spectacles which you purchase  for your own use. Contact lenses are also available through the Eyeplan scheme.      Back to top

What happens at a Contact Lens Trial?

You will need to have an up-to-date spectacle prescription. If you have not had a recent eye examination, this will be the first step.

Before any lenses are placed in your eyes, we will want to discuss:-

  • Why you want lenses and when you hope to wear them.
  • Your work and hobbies, health and any eye problems past or present.
  • The costs involved.
  • Different types of contact lenses and their good and bad points.
  • The risks involved in contact lens wear, and how to reduce them.

The shape of your eyes will be measured and the front of your eyes examined very closely using a sort of microscope called a Slit Lamp. During this examination we will  be assessing the eyelids and tears as well as the health and clarity of the Cornea (the clear window at the front of the eye).

If all is well then a contact lens will be placed in each eye and you will wear them for about half an hour to see how your eyes react and give you a chance to see what  wearing lenses is like. At the end of that time the fit and power of the lenses will be checked to make sure we know which lens will be right for you. Sometimes more than one lens will be tried in each eye.

Subject to a satisfactory trial then lenses will be ordered for you and an appointment made for you to be taught how to insert/remove the lenses and care for them.

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