The eye is made up of a clear dome-shaped structure called the cornea and an underlying lens which focuses light rays onto on a light sensitive layer of tissue at the back of the eye called the retina. The retina converts these light rays into electrical signals and sends them to the brain for processing. Problems with the cornea’s focusing ability can lead to refractive errors. Refractive errors are vision problems that happen when the shape of the eye keeps you from focusing properly.
Laser- assisted in-situ keratomileusis, commonly called LASIK is a surgical procedure performed to reshape the cornea for the correction of refractive errors. During LASIK surgery, a laser is used to alter the shape of the cornea so that light rays focused on it fall accurately onto the retina (light-sensitive region of the eye).
Lasik eye surgery may be performed to correct most vision problems including nearsightedness, astigmatism and farsightedness.
Myopia (nearsightedness) is a vision disorder in which distant objects appear blurry and closer objects can be visualized clearly. This is caused when the structure of the eyeball is too long or when the cornea is too curved.
Astigmatism (blurred vision) is an eye condition in which the vision is blurred due to an irregular shape of the cornea or curvature of the lens.
Hyperopia (farsightedness) is an eye condition in which distant objects can be seen more clearly than objects that are near. This is caused by an eyeball that is too short or a cornea that has too little curvature.
Types of Lasik.
Different types of LASIK procedures are available and your doctor will determine the appropriate type of surgery depending on your specific condition.
Some of the types include.
Custom LASIK: Custom LASIK employs Wavefront Technology, software which measures precisely how light travels in your eye. The software performs a detailed analysis of how your eye processes images and this information is sent to the laser for your doctor to perform the procedure and alter your cornea. Wavefront technology helps achieve individualized vision correction results impossible with conventional LASIK surgery.
Bladeless LASIK: Conventional LASIK surgeries make use of a special surgical cutting instrument known as a microkeratome to incise the cornea and create a corneal flap. Bladeless LASIK uses a precise high-energy laser instead of a blade to create the corneal flap. Though both bladed and bladeless LASIK procedures are safe and effective, bladeless LASIK procedures have been known to create fewer complications to the corneal flap.
Before undergoing Lasik surgery, your medical history is evaluated and an eye examination is performed. Various parameters such as corneal thickness, air pressure, refraction and pupil dilation will be measured. You will be instructed to stop wearing rigid gas permeable contact lenses for at least 3 weeks before your initial evaluation, and other types of contact lenses for at least three days before your evaluation.
The LASIK procedure only takes about 10 minutes to complete. Anaesthetic drops are instilled to numb your eye for the procedure so you won’t feel any pain. During the surgery, a lid speculum will be placed to keep your eyelids open. A suction ring is placed on the eye to create high pressure on the cornea. During this period, you may feel some pressure and slight discomfort, and your vision will go dim.
Depending on the type of Lasik, your doctor will either use the microkeratome, a blade device to create a corneal flap, or a laser if you are undergoing bladeless lasik. After the flap has been created, the suction ring is removed. The corneal flap is then peeled back to expose the underlying corneal tissue. An excimer laser is used to reshape this corneal tissue. After the reshaping is completed, the corneal flap is placed back into its original position. No stitches are needed to keep the flap in position. At the end of the procedure, a shield will be placed around your eye for protection. This shield prevents you from rubbing your eyes or applying any pressure until healing occurs.
Post operative care.
Following the surgery, you may experience some burning, itching, or a feeling that something is in your eye. You may also have slight discomfort or mild pain, for which your doctor will prescribe pain medications. Initially, your eyes will water or tear and your vision will be blurry or hazy. This should improve as healing occurs.
You will be instructed to avoid rubbing your eyes, swimming, participating in contact sports, or using lotions, creams or makeup around the eyes for at least a few weeks after surgery. You may be prescribed antibiotic drops and anti-inflammatory drops to prevent infection and inflammation. In addition, artificial tear drops are prescribed to help lubricate your eyes. Your doctor will schedule a follow up visit with you to assess your progress and vision status. Advantages.
Some of the advantages of LASIK eye surgery include:
Procedure is quick and generally painless.
Bandages or stitches are not needed.
Adjustments can be made many years after the initial surgery if needed.
Reduces or eliminates a person's dependency on glasses or contact lenses.
The disadvantages of LASIK eye surgery include:
Alterations made to the cornea are not reversible after surgery.
Problems or errors made during surgery can permanently affect your vision.
Rarely, LASIK can worsen your vision.
As with any surgery, there are risks and complications may occur.
In the first 24-48 hours following Lasik eye surgery you may experience some discomfort, blurry vision and tearing which should resolve.
Complications can include fluctuating vision, difficulty driving at night, dry eyes, glare, or seeing haloes around lights. Other risks can include over or under correction of vision, results that don’t last, or rarely, loss of vision.
Lasik eye surgery is performed to improve your vision by permanently changing the shape of the cornea. It can be used to treat common vision problems such as near-sightedness, farsightedness and astigmatism. Lasik can reduce your dependency on glasses or contact lenses.