Use of contact lenses has now come to stay as more and more people, who have to wear glasses, prefer to use contact lenses, the use of which has its own advantages and disadvantages. Since sale of contact lenses yields more money, the opticians and doctors advise their patients to use contact lenses, instead of spectacles.
First contact lens was processed and introduced to the world as far back as 1887 which had two glass layers within which a substance, called ‘gilletine’ was inducted. At that time, there was no method to measure curve of the eye. But due to their heavy weight, such lenses could not gain prominence due to obvious factors. It was in 1943 that first plastic lens was processed and introduced to the medical world.
The plastic contact lenses could be easily-fitted on the front portion of the eye (s) and were called scleral contact lenses but couldn’t gain popularity. Thereafter, corneal contact lenses were processed and introduced in the market in 1948. These lenses can be easily fitted over the transparent part of cornea and are quite easy to fit and remove, whenever necessary.
TYPES OF CONTACT LENSES
Three types of contact lenses are in use now-a-days, viz.
1. Hard contact lenses
2. Soft contact lenses and
3. Semi-soft contact lenses
PURPOSE BEHIND USE OF CONTACT LENSES
□ Cosmetic consideration (especially in the case of unmarried girls).
□ To get rid of habitual wearing of glasses.
□ Easy to use, remove and maintain.
□ No fear of misplacement and/or loss.
□ Its use decreases number of eye-sight (though not in all the cases).
□ Certain visual defects get automatically removed.
□ Provides better eye sight and visibility.
DISEASES WHICH NEED USE OF CONTACT LENSE
□ Astigmatism (defect of vision in which image of an object is distorted).
□ Keratonconus (Conical Cornea).
□ Diplopia (Double Vision).
□ Anisometropia (a condition in which the power of refraction on one-eye differs markedly from that in the other).
□ Myopia (farsightedness).
All the afore-mentioned and some other conditions are attempted to be rectified by use of contact lenses. Some problems and difficulties caused by use of spects are removed by use of contact lens. A person who habitually uses spects has a field of vision shorter, especially when number of glasses is on the lighter side, but this defect is removed by use of contact lenses which move and rotate with the movement of eye, and one has not to exert his eye while looking through contact lenses.
GUIDELINES/PRECAUTIONS
It is not that use of contact lens is totally free from hazards. Following points should be borne in mind before, during and after the use of contact lens:
□ If contact lens is not cleaned at the time of use, eyes can get infected by bacterial invasion which can result in variable infections.
□ Wash the lens properly with the solution provided by the doctors/opticians.
□ Be extra careful while fixing and removing the lenses.
□ If there is a different number for each lens, keep this fact in mind and keep each one in the plastic container which is marked with ‘L’ (Left) and ‘R’ (Right).
□ If you feel the number has changed, at once contact your doctor/optician.
□ Protect your contact lenses from dust, smoke and strong lights.
□ Remove the contact lenses before you return to bed.
□ Never rub your eyes while eyes are fitted with contact lens.
□ Careless handling and fixing of contact lenses hurriedly or while removing the same, may even injure your eyes.
□ If size of the contact lens is not exact and precise, i.e., not according to the size of the eyes or curve is not in order, even then one can have pain, irritation, itching, lacrimation, or due to scratches on the lens, Hence get your lenses fitted by an experienced optician/doctor.
□ Due to wrong fitting water may accumulate within the lens which can cause blinking, pricking and displacement of the lens. But all such complaints do occur initially and users of contact lenses shouldn’t give up their use under disgust or pseudo fear.
□ Do not use hard lenses, rather use soft or semi soft lenses.
□ Use solution meant for cleaning the lenses.