Refractive Errors - Eye Condition - We Care Health Services
A refractive error is a condition of the eye in which a clear image fails to focus on the retina due to optical causes.
Myopia (Nearsightedness) :
In a myopic eye, the light rays are passed through the cornea and lens but the point at which they converge (focus) is in front of the retina, not on the retina. A person with myopia has blurry vision at distance and is in clear focus at near.
Hyperopia (farsightedness) :
In a hyperopic eye, the light rays do not converge or focus by the time they reach the retina. Hyperopic patients can focus on more distant objects, but not images that are close at hand. Is the opposite of myopia, distant objects are clearer than near ones.
Astigmatism :
With astigmatism, the rays of light do not converge into a single point but form a line on the retina. There are various types of astigmatism included regular, mixed and irregular astigmatism. Astigmatism is a condition which can blur vision both at near and far.
Symptoms :
1. Blurred vision
2. Difficulty reading or seeing up close
3. Crossing of the eyes in children (Esotropia)
The symptoms described above may not necessarily mean that you have a refractive disorder. However, if you experience one or more of these symptoms, contact your eye doctor for a complete exam.
PROCEDURE
LASIK is a surgical procedure that uses a laser to correct nearsightedness, farsightedness, and/or astigmatism. The goal is to reduce or eliminate the patient's need for glasses, or contact lenses.
LASIK eye surgery is performed under anesthetic eye drops. The microtome is used to create a thin corneal flap, which is opened like the page of a book. The excimer laser is then used to sculpt ultra-thin layers of the remaining cornea to change its shape. This device is a mechanical shaver that contains a sharp blade that moves back and forth at high speed. This shaver is placed in the guide tracks of the suction ring and is advanced across the cornea using gears at a controlled speed. This process creates a partial flap in the cornea of uniform thickness. The flap is created with a portion of the cornea left uncut to provide a hinge. After the suction ring and microkeratome have been removed, the corneal flap is folded back on the hinge exposing the middle portion of the cornea. The excimer laser is then used to remove tissue and reshape the center of the cornea. The amount of tissue removed is dependent upon the degree of near-sightedness that is being corrected. In the final step, the hinged flap is folded back into its original position. The front surface of the eye is now flatter since the flap conforms to the underlying surface. In effect, the change made in the middle of the cornea is translated to the front surface of the cornea.
The corneal flap is returned, and bonds without the need for stitches. The effect of the removal of tissue results in better focusing onto the retina, and clearer vision with out corrective contact lenses or glasses.
The visual recovery is virtually immediate. The person can see quite clearly within two hours and the full result is achieved in 5-7 days. The post-operative medication is required only for 3-4 weeks, that too in reducing dosage.
Some of the benefits of Laser Vision Correction are: Decreased dependency on glasses or contacts, convenience with travel and recreational activities, no hassle with contact solutions, glasses, clip-ons, etc. Clear, natural vision.
The people who are likely to be immensely benefited with LASIK include sports persons and professional sports persons, persons in show business, stage artists, and people with public dealing jobs and career.
To know more about us or other details visit at http://www.indiahealthtour.com
By Dr. Sarita Kumawat
We Care Health Services
Tags: cornea, corneal flap, eye light rays
