Soft Contact Lenses
|
Soft contact lenses were first developed in 1959 by a Czech chemist named Otto Wichterle who successfully developed the hydrophillic (water loving) gel used to make the lenses. Since then Hydrogel lenses as they were called changed little over the years. Particular lens designs were different, however, aside from a few minor changes the material the lenses were made from stayed basically the same.
The major draw back to conventional hydrogel lenses has always been their oxygen transmissiblity, meaning how well they breathe. The cornea (the clear window of the eye) is clear, however, the mechanism by which it stays clear is to suppress blood vessels from passing through it and to keep it's structure completely uniform. Because the tissue is devoid of blood vessels it needs to derive it's oxygen from other sources and the biggest source of this oxygen is the air around us. Oxygen dissolves from the air into the tears and is then passed on to the cornea. If there is a barrier, ie a contact lens, between the air, tears and the cornea then the oxygen exposure is not cut off but diminished.
|
|
This has always been a cause for concern for practitioners and patients alike although with modern life getting more hectic and demanding the situation is a little more critical as hydrogel lenses can only be worn for limited periods of time.
It is only within the last decade that we have solved this issue and made it possible for materials to breathe more and thus enable the wearer to use their lenses comfortably for longer. Silicon Hydrogel materials are now widely available and offer a much higher oxygen transmissability. The development road has been rough, however, as silicon (derived from silica which is sand) although very breathable is fairly stiff and hydrophobic (hates water), this is not an ideal contact lens material.
Different generations of materials offer vastly different attributes from stiffer to softer, from very breathable to moderately so and much more. For the best lens suited to your needs we offer a full consultation and discussion about your lifestyle and can recommend what's best for you.
It is only within the last decade that we have solved this issue and made it possible for materials to breathe more and thus enable the wearer to use their lenses comfortably for longer. Silicon Hydrogel materials are now widely available and offer a much higher oxygen transmissability. The development road has been rough, however, as silicon (derived from silica which is sand) although very breathable is fairly stiff and hydrophobic (hates water), this is not an ideal contact lens material.
Different generations of materials offer vastly different attributes from stiffer to softer, from very breathable to moderately so and much more. For the best lens suited to your needs we offer a full consultation and discussion about your lifestyle and can recommend what's best for you.
