What is LASIK?
The vision correction procedure widely known as
LASIK is actually nowadays a routine surgical procedure
elected by many people with impaired vision who wish to eliminate the need for prescription glasses and/or contact
lenses. The word LASIK is actually an acronym that stands for laser-assisted in situ
keratomileusis. LASIK eye surgery is an ambulatory procedure that does not require a hospital stay.
Shortly after the surgery, which generally lasts about five minutes per eye, most patients are able to walk out
of the eye doctor's office on his or her own. It is recommended that patients are accompanied to the LASIK eye
center considering the fact that a mild sedative is often used.
Before the doctor begins the procedure, numbing eye drops are
going to be applied to the eyes so the patient doesn't experience a lot of discomfort during the procedure. A
device that helps keep the eyes open is positioned beneath your eyelids to hold them wide open. While this sounds
like it might be uncomfortable it usually is not. The LASIK surgeon creates a flap that allows the cornea--the
outer lens of the eye--to be slightly lifted. A precision laser is utilized to create the flap. The doctor folds
the hinged flap back so that the surface of the cornea can be corrected using a different type of laser known as an
excimer laser. The excimer laser works by using an ultraviolet light beam to smooth the surface and remove
microscopic pieces of tissue from the cornea in order to reshape it.
The cornea can be described as the portion of the eye that focuses light
to produce an image onto the retina. It functions a lot like the lens of a camera focuses and concentrates
light to produce images on photographic film. Most of the time the contour of the cornea is not optimal
and the image projected onto the retina is blurred or distorted in varying degrees. These defects in the
focusing ability of the eye are known as refractive errors. These errors lead to conditions that are known as:
myopia, hyperopia and astigmatism.
Those individuals afflicted with myopia, or nearsightedness, cannot see distant
objects as clearly as near objects. People with the vision condition known as hyperopia, or farsightedness, have the opposite
problem where they have much more trouble seeing near objects as clearly as far away objects. Astigmatism can be described as a distortion of the image on the
retina resulting from irregularities on the cornea. Some people even suffer from astigmatism along with either
nearsightedness or farsightedness. Both nearsighted as well as farsighted people today can enjoy improved vision
as the result of LASIK.
There are three primary types of refractive errors: myopia, hyperopia and astigmatism.
Persons with myopia, or nearsightedness, have more difficulty seeing distant objects as
clearly as near objects. Persons with hyperopia, or farsightedness, have more
difficulty seeing near objects as clearly as distant objects. Astigmatism is a
distortion of the image on the retina caused by irregularities in the cornea or lens of
the eye. Combinations of myopia and astigmatism or hyperopia and astigmatism are
common. - U.S. FDA
The basic goal of the LASIK procedure is to return the cornea
to a normal range of focusing power. Precise and controlled removal of corneal tissue by a special laser reshapes
the cornea changing its focusing power. After the cornea is reshaped after a successful procedure, it will do a
better job of focusing light onto the retina, which will result in sharper, clearer
The vast majority of patients experience some mild discomfort
for a day or two after laser eye surgery. This is one of the main advantages of today's LASIK compared to vision
correction procedures from several years ago which often resulted in pain that lasted for several days. Older
technologies such as Radial Keratotomy (RK) are surgical procedures where a blade is used to cut the
cornea and change its shape and contour. Doctors often prescribe eye drops after LASIK in order to prevent dry
eyes which is one of the most common complaints.
There are a few basic criteria that need to be met before even
considering LASIK. As with any medical procedure, there are certain risks that one ought to be aware of and take
into consideration as a means to avoid the most common LASIK
Most LASIK doctors advise that patients
be at least 21 years old. One of the main reasons for this is that it is important that the person's vision is
somewhat stable. Younger people's eyesight can change quite a bit as evidenced by the sometimes frequent changes
in their eyeglass and contact lens prescriptions. It is common for a person's vision to stabilize at some point
during their twenties. An optometrist is best able to determine, based on the eyeglass prescription history,
whether the vision is stable enough for a corrective vision procedure.
There are several conditions which would preclude a person
from eligibility for LASIK. Conditions such as chronic dry eyes and conjunctivitis must be dealt with and resolved
before surgery is possible. Other more serious ailments such as cataracts and glaucoma may totally disqualify a
Pregnancy and its accompanying
hormonal changes can have an impact on a woman's vision so it is not a good time to diagnose vision deficiencies.
Also, pregnancy in general is not a good time to proceed with any type of elective surgery since there is always
the chance of complications or infection which have the potential to negatively affect the fetus.
Different types of LASIK eye surgery have evolved over the past couple of decades and
the technology is always improving. You can read the following articles to find out some general information on
some of the different types of laser vision correction that have been developed.
- Learn about the potential benefits
of this type of surgery.
- Also referred to as wavefront LASIK, geared towards
correcting higher order aberrations.
- potentially less invasive than traditional LASIK.