The power of a LASER

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The power of a LASER

• Written by Nilisa Crespo

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What's the big deal?

• Lasik eye surgery has been the new epidemic since
  contacts and glasses. Many see this as a
  remarkable discovery while others see it as a
  gateway to poor eyesight. How do we trust the
  power of a laser to cure poor eyesight and make
  it 20/20 vision? There are many risks as well as
  benefits. How do we take the plunge to something
  so risky? The eye is a complicated organ that
  requires an exact arrangement of components to
  function. If even one of these components is not
  exactly the correct shape, then light that falls
  on the eye will not be focused correctly. For
  centuries, people have relied on external lenses
  to alter the angle of the light entering the eye.
  Whether in glasses or contact lenses, they have
  proven invaluable in the correction of poor
  vision. While external lenses will remain popular
  for the future, advances in technology have made
  it possible for surgeons to alter the shape of
  the eye itself. This is a great advancement that
  has changed the many lives of individuals.

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Glasses or Contacts?

• For many years people struggle with the constant
  battle with glasses and contacts. Glasses have
  never been harmful to the naked eye. Instead they
  have been more of a hassle then a way to better
  eyesight. They are fashionable and are extremely
  safe. Unfortunately they are not for everyone.
  There are people who prefer contact lenses.
  Contact lenses are the easy solution to poor
  eyesight. They come in different colors and
  shades bringing a lot of individuality. Even
  though contact lenses are unique and easy to
  manage they do come with a lot of risks. For
  example in order to wear contacts you need
  solution. That solution may harm your eyes and
  there is an increased risk of corneal infections,
  scratches, and scrapes. This leaves many people
  with lasik eye surgery to turn to. Nowis it the
  clear choice to bad eyesight?

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What is lasik eye surgery?

• -Lasik eye surgery is a popular surgical approach
  used to correct vision in people who are
  nearsighted, farsighted, or have astigmatism. It
  is a procedure that permanently changes the shape
  of the cornea which is the clear covering of the
  front eye using an excimer laser. A knife called
  a microkertome is used to cut a flap in the
  cornea. A hinge is then left at one end of this
  flap. The flap is folded back revealing the
  stroma which is the middle section of the cornea.
  Pulses from a computer control laser vaporization
  and a portion of the stroma is replaced.

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How the procedure works
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Advantages of going under the knife

• There are many advantages to this procedure as
  well as disadvantages. Some of the advantages
  include
• It corrects vision. Around 80 of patients will
  have their desired vision after LASIK laser eye
  surgery.
• This suregry involves very little pain.
• Vision is corrected nearly immediately or by the
  next day after LASIK laser eye surgery.
• Recovery is quick and usually no bandages or
  stitches are required after LASIK laser eye
  surgery.
• Adjustments can be made years after LASIK laser
  eye surgery to further correct vision.
• After having LASIK laser eye surgery, most
  patients no longer need corrective eyewear.

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Disadvantages

• Some of the disadvantages include
• Changes made to the cornea cannot be reversed
  after LASIK laser eye surgery.
• Corrections can only be made by additional LASIK
  laser eye surgeries.
• Surgery is expensive, costing 2,200 to 2,250
  per eye compared to the cost of glasses and
  contact lenses, the price is relatively good.
• Problems may occur when the doctor cuts the flap,
  which can permanently affect vision.
• Surgery can cause a loss of "best" vision with or
  without glasses at 1 year after surgery. Your
  best vision is the highest degree of vision that
  you achieved while wearing your contacts or
  eyeglasses.
• During lasik eye surgery Some patients experience
  discomfort in the first 24-48 hours after
  surgery.
• Infection and delayed healing
• Seeing halos around images
• Difficulty driving at night
• Fluctuating vision
• Dry eyes
• Some patients lose vision. Some patients lose
  lines of vision on the vision chart that cannot
  be corrected with glasses, contact lenses, or
  surgery as a result of treatment.

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What are the risks?

• Some patients lose vision. Some patients lose
  lines of vision on the vision chart that cannot
  be corrected with glasses, contact lenses, or
  surgery as a result of treatment. 
• Some patients develop debilitating visual
  symptoms. Some patients develop glare, halos,
  and/or double vision that can seriously affect
  nighttime vision. Even with good vision on the
  vision chart, some patients do not see as well in
  situations of low contrast, such as at night or
  in fog, after treatment as compared to before
  treatment.

• You may be under treated or over treated. Only a
  certain percent of patients achieve 20/20 vision
  without glasses or contacts. You may require
  additional treatment, but additional treatment
  may not be possible. You may still need glasses
  or contact lenses after surgery. This may be true
  even if you only required a very weak
  prescription before surgery. If you used reading
  glasses before surgery, you may still need
  reading glasses after surgery. 
• Some patients may develop severe dry eye
  syndrome. As a result of surgery, your eye may
  not be able to produce enough tears to keep the
  eye moist and comfortable. Dry eye not only
  causes discomfort, but can reduce visual quality
  due to intermittent blurring and other visual
  symptoms. This condition may be permanent.
  Intensive drop therapy and use of plugs or other
  procedures may be required. 

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Other forms of eye surgery include

• Other forms of eye surgery include.
• ALK This is used to correct vision in people
  with severe nearsightedness and slight degrees of
  farsightedness. As in LASIK laser eye surgery, a
  flap is created in the cornea so that the doctor
  can reach the underlying tissue. During this
  procedure, a laser is not used to correct vision.
  Instead, another incision is made on the sub
  layer of the cornea to reshape the cornea.
• LTK This is a new laser eye surgery is used to
  treat farsightedness and astigmatism. During LTK
  laser eye surgery, a laser beam uses heat to
  shrink and reshape the cornea. Vision is
  corrected in a matter of seconds, without any
  cutting or removal of tissue.
• AK This is not laser eye surgery, but a surgical
  procedure used to correct astigmatism. The cornea
  of people who have astigmatism is shaped like a
  football. AK eye surgery corrects astigmatism by
  making one or two incisions at the steepest part
  of the cornea. These incisions cause the cornea
  to relax and take a more rounded shape. This eye
  surgery may be used alone, or in combination with
  other laser eye surgeries such as PRK, LASIK, or
  RK.
• RK This eye surgery was once one of the most
  frequently used procedures to correct
  nearsightedness. However, since the development
  of more effective laser eye surgeries, such as
  LASIK and PRK, RK is rarely used today.

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When physics relates

• Science is a major component in surgeries.
  Physics is one of the most important components
  in this surgery. For example light is something
  we see everyday of our lives. It is everywhere.
  Its in our houses and it is outside. Light is the
  range of frequences of electromagnetic waves that
  stimulate the retina of an eye. Light travels in
  a straight line in a vaccum. When your body
  blocks sunlight you see a shawdow. If light from
  the sun is made visibleby dust particles in the
  air, the path of the light is seen to be a
  straight line. The straight line path of light
  has led to the ray model of light. A ray is a
  straight line that represents the path of a
  narrow beam of light.

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Light

• Materials that transmit light waves are called
  transparent materials. These are objects that can
  be seen through air, glass, and certain plastics.
  This material relates to contact lenses. Colors
  also play a major role. For example many people
  have brown eyes, grey, green, blue , and hazel
  eyes. Light can be formed from colored light in
  many different ways. A pigment is a colored
  material that absorbs certain colors and
  transmits or reflects others. A pigment particle
  is larger than a molecule and can be seen through
  a microscrope. A pigment is like an eye. They can
  both be seen through some kind of microscope.

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Reflections

• Reflections are a important factor to eyesight.
  The law of reflection states that the angle of
  the reflection is equal to the angle of
  incidence. Refraction is the bending of light
  rays at the boundary between two media.
  Refraction occurs when the incident ray strikes
  the boundary at an angle. The dutch scientist
  Willebrord snell stated that a ray of light bends
  in a such a way that the ratio of the sine of the
  angle of incidence to the sine of the angle of
  refraction is a constant. This is when a ray
  travels. This is also like looking into a mirror.
  Thats why eyes are sensitive and should be
  handled with care. In the retina, sensory cells
  called rods and cones change the photons of light
  into electrical signals, which are then
  transmitted to and interpreted by the brain. The
  ability to focus the light on the retina depends
  on the shapes of the cornea and the lens, which
  are controlled by their inherent shapes, their
  stretchiness the shape of the eyeball and sets of
  attached muscles. So, when you look at something,
  muscles attached to the lens must contract and
  relax to change the shape of the lens system and
  keep the object focused on the retina, even when
  your eyes move. This process is controlled by the
  nervous system.

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Solution

• Furthermore, lasik eye surgery is a very risky
  surgery. It can improve your vision, worsen it or
  even leave it exactly the same. The long term
  effects are too hazardous to even risk with.
  Lasik eye surgery is the clear the solution to
  having good eyesight are the risks worth it?
  Should people just stay with the original ideas
  of glasses and avoid possible damage to our eyes?

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SEE YOU LATER!!!!