The process involved in visibility is that the light rays gets bent (refracted) as they pass through the cornea and the lens. The light is then focused on the retina which converts the light-rays into messages that are sent through the optic nerve to the brain. The brain interprets these messages into the images we see.
Refractive errors occur when there is a change in the length of the eyeball or in the shape of the cornea due to which the light does not correctly focuses on the retina, thus resulting in impaired vision.
The common refractive errors are :
Myopia/ Nearsightedness :
The objects that are near to eyes appear clearly while objects far away appear blurred. Here the eyeball is longer and cornea to steep so the light focuses in front of the retina instead of on the retina. Myopia is usually inherited and mostly diagnosed in childhood.
Hyperopia/Farsightedness :
Here the objects far from the eyes appear clear while the near objects are blurred, while in severe hyperopia the vision at all distance is blurred. The eye is too short in this case or the cornea is too flat, as a result the image focus at a point behind the Retina.
Presbyopia(loss of near vision with age) :
At older age i.e. age after 40 the flexibility of the eye lens decreases thus loosing the power to focus. This result in difficulty in reading at the closer range.
Astigmatism :
A normal cornea is round and smooth but when you have astigmatism, the cornea curves more in one direction than in the other and light entering the cornea is focused equally on all directions. Thus resulting in the blurred vision at all the distances.
Treatments offered at Jain Netralaya :
Glasses :
Most affordable and easy to maintain remedies which is in existence from very old days. The test is performed by coputerised machine and the appropriate lenses to correct your refractive error is recommended to you. The disadvantages are that sometimes they restrict peripheral vision, can cause magnification of images or cause visual aberrations. Most of the people do not like their look with a spectacle on their face.
Contact Lens :
This is a little advanced non-operative method to cure the refractive errors, here a lens is prescribed by the consultant as per the refractive index measured and the patient wears it inside the eyes.
The contact lens is more comfortable in terms of looks, and better peripheral vision but it carries with it the risk of higher infection so needs much more care and maintenance. Also it is quite uncomfortable in case of dry eyes.
Refractive Surgical Procedures :
These surgeries aim to change the shape of the cornea permanently. This change in eye shape restores the focusing power of the eye by allowing the light rays to focus precisely on the retina for improved vision. There are many different types of refractive surgeries namely LASIK,PRK,LASEK, RLE, EpiLasik, PRELEX, Intacs, Phakic intraocular lens implants, AK or RLI and RK
Refractive surgery might be a good option for you if you want to decrease your dependence on glasses or contact lenses and you are free of eye disease.