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Answers
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The
Comprehensive Eye Examination
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How often should I have my eyes examined?
Simply, once per year for everyone. But when our patient's ask
us this question, the answer is tailored for the patient's
specific age group:
From birth to one year- Yes, we examine babies!
90% of a complete, comprehensive eye examination can be done
without the patient ever saying a word. It is important to see
an infant before one year of age to identify possible
congenital bnormalities or birth defects in the eye. If
untreated, these defects may have a lifelong consequence.
Age 1 to Age 4 - These are the formative years for the
development and education of the visual system. If the eyes are
not seeing clearly during this period, the brain never learns
to interpret the visual signal. Consider what would happen if
during the first four years of life your feet had been tied
together. Chances are, you would never walk correctly. The same
happens with the visual system if the vision is not clear from
the start.
Kindergarten through 18 years old - Education is obviously
one of the keys to success in life. Young children are not sure
what they should be able to see, so many struggle in the
classroom attempting to see the chalkboard or have eyestrain
while reading. Adolescents soon find their studies quickly
increasing as they progress towards college. School is tough
enough today on our children without having the handicap of
poor vision. Progression of nearsightedness and development of
binocular vision disorders are common during this period.
18 through 40 years old - As our society becomes more
computer-oriented; as the normal workday has become 10+ hours;
as stress increases and deadlines are shorter... all of these
are made worse if the eyes are not seeing perfectly. Many
times, optometrists help their patients with reading glasses,
or contact lenses, or driving glasses, that make a world of
difference and gives you back the edge.
40 to 55 years old -
First, blurry vision while reading is certain in this age
group. The loss of focusing ability called Presbyopia occurs.
This is a normal condition that everyone will experience.
Routine updates in your glasses or contact lens prescription
will assure comfortable reading. Second, these are the years
when risk of serious eye disease can develop. A thorough,
yearly eye examination with drops to dilate the pupils assist
in diagnosis and allow early treatment. Early treatment in many
eye disease can limit the severity of damage that could occur
from the disease.
55 and beyond - Of most importance is the health portion
of the eye examination. Cataracts, glaucoma, and retinal
disorders are among the most common eye diseases. Again, the
importance of early detection to allow treatment can not be
understated.
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My child receives vision screenings at school. Isnt this
enough?
First, it is important to verify exactly what the screening
included at school. Most are simply a test to see where the
child can read on the eye chart. The typical failure criteria
is vision worse than 20/30. This means that if your child can
see 20/30, he or she is passed. Ask your eye doctor to
demonstrate to you exactly what 20/30 vision looks like through
trial lenses. Guaranteed, you would not be happy with 20/30
vision if that was the best you could see. Also, simple 20/20
vision does not mean perfect eyes. The visual system should be
thought of as a complex optical instrument, not only including
the eyes, but the visual pathways through the brain to the
sight center and how the information is processed. There is
also a complex mechanism which controls eye movement and
alignment. Just because a person can read "the bottom
line" on the eye chart does not necessarily mean the eyes
are working as smoothly and efficiently as possible. Also,
screenings only test for nearsightedness. A person who is
farsighted will be tested as having 20/20 vision, but may have
terrible eyestrain when reading.
We tell parents this, "The school nurse and her volunteers
work as hard as possible to identify those children who may
have vision problems. However, their time and equipment is
limited. A Comprehensive Eye Examination with a trained doctor
of Optometry is a simple, inexpensive way to be 100% certain
that your child is seeing as best as possible."
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How do I know if I received a quality exam and can feel
confident with my optometrist?
There are many tests which must be completed to ensure a
comprehensive exam was completed, but remember to listen to how
you feel when its over. Did the doctor take time to ask about
your life and health? Was the doctor a good communicator and
compassionate? Did the doctor educate you about your eyes so
you will be better able to take care of them? Does your doctor
focus on prevention of eye diseases as well as treatment and
rehabilitation? Make sure that the doctor had a good, long look
inside your eye. The process takes several minutes, and even
though most of us dont like the bright light in our eyes, it
is necessary to complete a thorough examination. Sure,
technology continues to accelerate each year and optometrists
are equipped with more tools than ever before, but the
foundation of eyecare remains the caring human being behind the
instrument, your optometrist.
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Eye Health
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How can an eye doctor detect health problems such as high
blood pressure and diabetes through a routine, comprehensive
eye examination?
Actually, not every eye exam performed by an eye doctor will
indicate if a patient has an underlying systemic health condition
such as high blood pressure, diabetes, Multiple Sclerosis,
leukemia or other blood dyscrasia, cancer, arthritis, etc. A
thorough eye examination demands time and care, and must
include not only the determination of glasses prescription, but
intense examination of the ocular health of the eye that must
include dilation of the patient's pupils with drops. A
Comprehensive Eye Examination should always include a
refraction to determine spectacle prescription, a detailed case
history, biomicroscopy to examine the health of the outside of
the eye at the microscopic level, ocular neurological testing,
visual field (peripheral vision) testing, glaucoma testing and
dilation of he pupils.
We are able to detect systemic disease because the eye is
comprised of the same tissues that make up the rest of the
body. For example, the retina and optic nerve is made of the
same nervous tissue that is found in the Central (brain) and
Autonomic (peripheral) Nervous System. Consequently, Multiple
sclerosis, a neurological condition which effects the nervous
system, will also frequently effects vision and the appearance
of the optic nerve.
Another example is diabetes. Diabetes is devastating to the
vascular system in the body. The eye, kidneys and feet have the
most fragile blood vessels, therefore these blood vessels here
are typically effected first in the disease process. The eye is
unique because the blood vessels actual lay on top of the
retina. Therefore when your optometrist looks inside of your
eye, they are seeing blood vessels with no overlying tissue to
obscure their view. Nowhere else can a doctor see a blood
vessel like this without cutting the patient open! Again, this
internal evaluation of the eye can not be completely performed
without dilating the pupils.
Arthritis can be seen in the eye because the fibrous connective
tissue that makes up the sclera is the same connective tissue
which cushions our joints. Inflammations of the connective
tissue (arthritis) therefore can effect the joints (arthritis)
and the sclera (scleritis).
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What are some factors that can contribute to dry eyes?
There are many factors that can cause the front of the eye to
be inadequately lubricated. Normally when you blink, the tears
are distributed across the cornea (the clear tissue which
covers the colored part of your eye) to bathe and nourish it.
This keeps the cornea comfortable and healthy, allowing old
cells to slough off and new cells to grow. The first factor
linked to dry eye is aging. As you age, the glands that produce
the tears (the Lacrimal and Meibomian glands, along with Goblet
cells) decrease in function. Second, many medications,
including birth control pills, anti-histamines, and high blood
pressure medications, can cause dry eyes. Next, seasonal
allergies can dry the eyes out as well. Also, anyone who smokes
cigarettes or who is exposed to second-hand smoke may suffer
from dry eyes. Contact lenses can cause dry eyes by increasing
lubricating demands on the tears as they absorb water, and/or
disturb the natural tear flow across the eye. Excessive
computer use is another culprit, as most people blink less
frequently when staring at their screen. Individuals who
consume alcohol and caffeine tend to be dehydrated regularly
and this decreases the amount of tears produced. Finally, some
systemic diseases cause dry eyes as well, like Sjogrens
Syndrome. If you think your eyes are dry, you should consult
with your optometrist, as there are several types of treatments
that range from using artificial tear lubricating drops, to a
procedure called punctal occlusion where the drainage holes
(punctas) where tears leave the eye are plugged with tiny
implants. The doctors of Vision Clinics perform all types of
treatment for dry eyes.
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Can excessive computer use cause eye problems?
Yes, there is a group of symptoms referred to as Computer
Vision Syndrome. This condition includes eye fatigue, blurred
vision, increased effort while focusing, dry eyes, transient
ghosting/doubling of images, light sensitivity, possible
increase in nearsightedness, and even head, neck, and
backaches. These symptoms occur largely because the eyes were
not designed to stare at, and perform "visual
acrobatics," with a computer monitor all day. Also, most
computer workstations are not designed to be "user
friendly."
Since using a computer requires that you look at the monitor,
selecting the easiest one on the eyes is important. The best
type of monitor has a large, flat LCD screen. Older
monochromatic monitors have flicker, poor contrast, and glare,
causing considerable strain on the visual system. They also are
usually reverse contrast screens, where the letters are white,
green or amber on a black background. This makes reflections
easily seen. Reflections are seen at different depths in the
screen and cause excessive focusing and refocusing of the eyes.
The mirror-like images of the overhead lights behind you, or
even your own white shirt can cause the eyes to keep changing
their depth of focus. Repositioning the monitor or purchasing a
polarized screen cover can also eliminate reflections on your
monitor screen.
Dry eyes are quite common among computer users. As our
concentration is focused on the ever-changing computer image,
our blink frequency decreases. The average person blinks 12
times per minute, however, studies have shown an individual
using a computer may blink as little as only four time per
minute. This situation is only made worse with the poor
lighting in many offices, contact lens wear, smoking, or
medication side effects. We recommend to our patients who use
computers to use an artificial tear drop (not a
"red-out" formula) at least four times during the
day.
Take a 2-minute "visual break" every 20 minutes by
looking at objects that are at least 20 feet away. This rests
the eyes focusing mechanisms and muscles. Do some light
stretching of your arms, neck and legs. This is essential for
increasing overall performance of the visual system for a full
day.
Consider the following suggestions to help arrange your monitor
(VDT) and keyboard to allow you to work productively and
comfortably: 1) the monitor should be 20 to 30 inches from your
eyes, 2) the top of the VDT just below horizontal eye level, 3)
the VDT should be tilted away from you at a 10 to 20 degree
angle, 4) the VDT and keyboard should be in line, 5) place document
holders just to the side of the VDT to minimize eye movements
and constant changes in depth of focus, 6) keep your screen
clean of dust and fingerprints.
Consider these suggestions regarding VDTs and lighting, to
improve your visual efficiency when using your VDT: 1) match
the level of brightness of surroundings to that of the VDT
screen, 2) keep contrast between the characters and the
background high, 3) minimize glare on the screen by using
dimmer-switches and anti-reflective and anti-glare coated
screens, 4) position your VDT perpendicular to windows or other
bright light sources to reduce glare.
Human eyes were made for most efficient operation at far
distances, but if you use the suggestions made here, you will
be able to use your VDT more productively, comfortably and
efficiently.
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What is a stye (hordeolum)?
A stye (or hordeolum) is an infection that occurs within the
eyelids. A stye usually begins as a subtle irritation of the
eyelid, or a foreign body sensation on the eye. Close
inspection will usually reveal a small red spot on the eyelid.
As the infection continues, the stye will become a painful, red
lump, causing the eyelid to become swollen. Eventually, the
swollen nodule may form a pustule, and drain. If the stye does
not resolve, the nodule may harden as the infective debris
solidifies.
A stye results from blockage of one or more of the small oil
producing glands (meibomian glands) that are found in the upper
and lower eyelids. These blockages trap the oil produced by the
glands and cause a lump on the eyelid that is usually about the
size of a pea. Bacteria that exist normally on the eyelid also
become trapped in the gland, and begin the infective process.
Treatment of styes involves persistent hot compress
application. Antibiotic drops, ointments, or other topical
applications are typically ineffective due to the infection
occurring in the deeper tissues of the eyelids. If the stye
does not resolve with heat, oral antibiotics, steroid injection
at the site of the swelling, or surgical incision and drainage
may be performed. The progression of treatment depends on the
severity of the symptoms, the frequency with which the stye
reoccurs, and the size of the lump.
Any lump should be evaluated by a doctor of optometry or
ophthalmologist before any treatment is initiated.
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What causes the floaters I see occasionally?
Floaters are many times described as little black colored
shapes ranging from strands to squiggles and clumps.
Fortunately, floaters are not usually a serious symptom of any
eye disease. However, if you notice showers of floaters that
suddenly appear along with flashes of light or decreased
vision, you may be experiencing a retinal detachment and should
seek immediate care. "Normal" floaters are tiny solid
particles suspended in the fluid that fills the eye (the
vitreous humor). These tiny objects make shadows on the retina,
and the brain interprets them as dark objects floating out in
front of your face. These floaters are more noticeable when
viewed against a white wall, a uniformly blue sky, or when
reading. You can have floaters at any age, but they tend to
increase as we grow older. There is nothing that can be done
about uncomplicated floaters, and are simply annoying to most
people. If the floater is associated with a retinal detachment,
immediate treatment is imperative. An eye doctor should be immediately
consulted, and an examination of your retina should be done
through dilated pupils to determine the floaters origin.
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Help me better understand what ultraviolet (UV) radiation
is and how it affects my eyes.
UV light comes from many sources including the sun, tanning
lamps, welding equipment, and computer monitors. There are
three different types of UV light called UVA, UVB, and UVC. UVA
radiation accumulates over time, is painless, and causes
irreversible damage (cataracts). UVB causes acute damage that
can be severe and painful, but usually temporary (sun burn).
UVC is absorbed by the ozone layer currently and does not reach
earth. Short-term exposure (minutes) to UV radiation can
produce photokeratitis, also called welders flash,
snowblindness, and sunburn of the eyes. Long-term exposure
(years) results in cataracts, retinal problems, eyelid cancer,
and premature wrinkling of skin around the eyes (crows feet).
Simple precautions include: 1) use an spf-15 lotion when
outdoors, 2) get UV coatings on all eyewear including spectacle
lenses and contacts, 3) wear sunglasses even on overcast days
because UV light passes through clouds, 4) wear a hat with a
brim, 5) never stare directly at the sun.
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Glasses
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From what material should I
get my spectacle lenses made?
There are several materials of which spectacle lenses can be
made. There is glass, plastic, polycarbonate and high-index
materials. Glass is the material that has the truest optical
properties and is least likely to scratch. However, glass is
easily shattered, heavy and thick, so for these reasons it is
usually not the material of choice. Plastic is lighter and
thinner than glass, and is more shatter-resistant, but
scratches more easily. With a scratch-resistant coating
applied, the plastic lens is nearly as scratch-resistant as
glass. Polycarbonate material is even lighter and thinner than
plastic, and is 10 times more impact-resistant. Additionally,
polycarbonate material has inherent UV protecting properties.
It is recommended for children, sports, safety, and patients
who may rely on only one eye (to provide as much protection for
the good eye). High-index material is the lightest and thinnest
material yet. With any given prescription, lenses made of
high-index material can be made thinner because it bends light
more quickly and thus focuses light with less material needed.
As everyones needs are different, and there are numerous
choices, this is something to discuss with a knowledgeable
eye-care professional.
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Why is an eyeglass prescription not a contact lens
prescription?
The doctors in our office are frequently asked to give a
"contact lens prescription" after doing an eye
examination for glasses or even after placing a
"trial" contact lens on a prospective contact lens
wearer's eye. When the patient's request is refused, they
understandably become upset.
During the routine examination, doctors perform certain tests
which give more information about what contact lens might be
worn. Additional things to be considered are:
1: History - occupation, age and prior contact lens history.
2: General Health of the patient
3: Health of the patient's eye- the tear composition, the
corneal integrity, etc.
4: Curvature of the cornea - amount and degree of corneal
astigmatism.
If the doctor feels that the patient is a good candidate for
contact lenses, a "trial lens" must be placed on the
eye. EVERY LENS IS A "TRIAL LENS" UNTIL AFTER SEVERAL
WEEKS (OR LONGER) OF WEAR AND THE DOCTOR AND PATIENT ARE
SATISFIED ABOUT THE LENSES SUITABILITY.
A lens that looks satisfactory at the initial dispensing, may
tighten while being worn and cause discomfort of blurred
vision. The materials from which the lens is made may be
incompatible with the patient's eye tissue or tear layer. This
cannot be determined at the time of the original fitting.
Therefore, a doctor is not able to give a contact lens
prescription based solely on the preliminary findings of the
examination. The doctors at Vision Clinics, Ltd. insist that
thepatient enter into Contact Lens Management. This is a
prescribed period, usually lasting several weeks, in which the
contact lens fit, vision obtained, and their effects on the
eyes health is closely monitored.
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Why dont my "light-sensitive lenses" get dark
in the car, even when the sun is in my eyes?
Photochromic lenses (plastic "Transitions" or glass
"Photogray") are spectacle lenses that change from
light to dark. The darkening process requires direct exposure
to ultraviolet light (UV) to stimulate the chemical within the
lens, creating the darkening. When you are in the car, the
windows are coated to eliminate UV light. It is important to
know this when you are considering purchasing this type of
lens. If sun protection is important to you while driving your
car, consider a pair of polarized sunglass lens.
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What are some general safety tips
with respect to protecting the eyes during sports?
The top five sports with greatest percentage of eye injury
among children under 14 are as follows: baseball (21%),
basketball (16%), soccer (14%), football (13%), and hockey
(10%). For athletes ages 15 to 24, basketball is the highest
risk sport for eye injury (32%).
Even when wearing contact lenses while playing sports, eye
safety must be considered. Contacts may allow better clarity of
vision, but safety glasses should still be worn. For instance, a
soccer ball is too large to harm the eyeball directly, but a
racquetball fits into the eye socket easily. Yet, even while
playing soccer you are at risk to receive an eye injury with an
elbow or scratch to the eye. When safety glasses/sport goggles
are chosen, polycarbonate lenses are required for their
impact-resistance.
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Can drugstore-reading glasses be harmful to my eyes?
Possibly.There are several reasons that reading
"cheaters" purchased at the drugstore can contribute
to eye problems. First, they always have the same prescription
in each lens, and most people require a different power in each
eye. Therefore one eye will be over- or under-corrected,
leading to focusing disorders. Second, drugstore glasses never
include correction for astigmatism, which nearly everyone has.
Astigmatism blurs both distance and near vision. Even small
amounts of astigmatism, when left uncorrected, can cause
eyestrain and fatigue. Next, drugstore "readers" can
be harmful because they are not properly fitted. This includes
how the lenses are centered in front of the eyes. Every
prescription lens has an optical center. This point on the lens
must sit directly in front of the center of the pupil. If this
alignment is off even by a millimeter, it can cause prismatic
effects and distortion, all contributing to eyestrain and
fatigue. That is why it is important to have spectacles fit by
trained professionals. Remember that drugstore readers carry no
guarantee as to the optical quality of the lens material and
its shatter-resistance. Of most importance however, is the
importance of examining the health of the eyes, especially
during the years when near vision starts to decrease. Many
serious eye diseases are age-related. If you are experiencing
blurry vision, youll want a full eye examination by a
competent eye doctor to be sure that a more serious problem is
not occurring.
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Can drugstore sunglasses be harmful to my eyes?
Yes. Some sunglasses at drugstores have a decal that claims
100% UV (ultra-violet) protection. In reality, they have 100% of
the FDA minimum recommended UV protection, which amounts to
only 70% UV protection. This is deceptive, but legal,
unfortunately. The problem lies in the fact that UV light is
known to contribute to cataract formation and macular
degeneration, and therefore it is important to block 100% of
these harmful rays. We should buy sunglasses is to protect our
eyes 100%. Of course, fashion is important today as well, but
saving a few dollars on drugstore sunglasses may cost you
serious vision problems in the long run. Drugstore sunglasses
typically lack in optical quality. Cheap lenses cause
distortion, possibly decreasing the clarity of your vision, or
at least causing eyestrain. If you have ever worn cheap
sunglasses and had to remove them and rub your eyes, chances
are youve experienced poor quality-induced distortion.
Patients will claim they are too careless with their sunglasses
to invest in a nice pair. We tell our patients that if they
invest in a quality pair of sunglasses, they are much more
durable, and when they appreciate the quality, they will
happily take care of them. Think of your sunglasses as a
vision-saving device, and not just a fashion accessory.
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Contact Lenses
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Why are extended wear contact lenses (sleeping while
wearing contact lenses) unhealthy for my eyes?
This mode of wearing contact lenses is unhealthy for several
reasons. First, the cornea only gets oxygen from the air; there
is no blood supply or other circulation. While wearing contact
lenses, the corneas oxygen exposure is significantly reduced. "Overwear"
starves the cornea of oxygen and goes into a state of oxygen
deprivation called hypoxia. This signals blood vessels from the
white part of the eye (sclera) to grow into the cornea. This
neovascularization, or new blood vessel growth, is an attempt
to provide an alternative method of nurishing the corneal
tissue. Unfortunately, these blood vessels are not transparent
and blindness can occur if one of the blood vessels grow across
the center of the pupil.
Next, dirt and deposits on the lenses build rapidly. When the
lenses are not removed to be cleaned, rinsed and disinfected,
the protein and lipid coating thickens to an unacceptable
level. The health of the cornea is further is jeopardized as
oxygen is now diminished, and the dirty contact lens promotes
bacterial growth. Sleeping in contact lenses puts the wearer at
a 15-25% greater risk of corneal infections and ulcers; a
sight-threatening outcome.
In no instance do the doctors of Vision Clinics recommend
extended contact lens wear; even when a contact lens is
approved by the FDA for extended wear.
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Are bifocal contact lenses available?
Yes. You have several options to consider besides using reading
glasses over your contacts when your near vision starts to
decrease. In actuality, bifocal contacts have been available
since 1985. Bifocal contact lenses are available in soft and
rigid materials, and can be fitted for patients with
nearsightedness, farsightedness, and astigmatism. True bifocal
contact lenses fully correct both eyes for distance and near
vision simultaneously. This is most like your natural vision.
Bifocal contact lenses are a long-term solution to all levels
of presbyopia (loss of near vision after age 40). Just
recently, a two-week (daily wear) disposable soft bifocal
contact lens was released and we have already fitted many of our
patients. Contact lens technology is rapidly advancing, and the
doctors of Vision Clinics use all of the most current lenses
available, as well as the ones weve fit on patients for years.
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Are there any alternatives to bifocal contact lenses?
Yes. There are two alternatives. The first is to simply
purchase a pair of reading glasses for over your contact
lenses. When you look up from your reading, you will however
have to remove the glasses to see far away because reading
glasses are only focused for near. Many patients will select a
bifocal spectacle lens (either with the line or blended), to
allow them to look up from their reading and still be able to
see clearly into the distance without removing their glasses.
The next option you have is to be fitted into
"Monovision" contact lenses. Here, standard contact
lenses, many times identical to the lenses you are currently
wearing, are fitted to correct one eye for distance vision, and
the other eye for near vision. In actuality, as strange as this
sounds, there is an 80 to 90% success rate with the adaptation
to this system. We do caution our patients that there may be a
compromise in their vision, and they should test their
acceptance "slowly," but again, the vast majority of
patients are thrilled with their vision.
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What is the proper way to clean my daily-wear disposable
contact lenses?
The answer to this question depends on many factors. The term
"disposable" means that you replace the lenses on a
planned schedule instead of keeping one pair for an entire
year. Just saying that you wear disposable contact lenses means
nothing in terms of the proper care that is required. Many
other variables need to be known before advice on proper lens
care can be given. For example, there are many types of
disposable contact lenses, including 1-day disposables, 2-week
disposables, and 1, 2 and 3-month disposables. Lenses worn
for one day and then discarded do not need to be cleaned at
all. Daily-wear lenses worn for 1 month or less can usually be
cleaned with a multi-purpose solution only. This is a single
bottle that is used for cleaning, rinsing, and disinfecting.
When contact lenses are prescribed for wear of longer than one
month, an additional protein remover is usually needed. This
can be in the form of enzyme tablets, or a second liquid drop
that is added to your storage case. It might need to be used
daily or once a week. There are many factors that determine
this. Examples are the number of days per week and hours per
day the lenses are worn, your work and home environments, if
you smoke cigarettes, the cleanliness of your hands, the number
of years you have worn contacts, and the quality of your tears.
Some people have sensitive eyes and need to use solutions that
are preservative-free. As you can see, this is an important
discussion that we have with every patient. One final point
that should be made clear is that all 2-week disposable lenses
must be cleaned, rinsed and disinfected nightly upon removal.
Some patients are misinformed that they need not be clean at
all. This misinformation can lead to serious eye infections and
corneal ulcers.
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Refractive
Surgery
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Tell me about refractive surgery.
Refractive surgery is the newest and most exciting topic
related to vision. Refractive surgery is the actual correction
of refractive error (the need for glasses or contact lenses)
through permanent surgical techniques. There are numerous
surgical procedures being done, but essentially they fall into
four categories: 1. Incisional surgery where a scalpel or
similar instrument is used to cut into the cornea for
reshaping. (Example: Radial Keratotomy (RK) and Automated
Lamellar Keratomileusis (ALK)) 2. Laser light application to
the cornea which cause shape modification of the tissue.
(Example: PhotoRefractive Keratectomy (PRK)) 3. A combination
of incision and laser correction for both near and
farsightedness (Example: Laser In-Situ Keratomileusis (LASIK)) 4.
Intraocular surgical implant of corrective lenses (Example:
Clear lens extraction, Phakic lens implant, and Corneal Rings).
Each individual surgical procedure has its risks and benefits,
and each individual patient should be personally evaluated to
determine which treatment they are best suited for. Seeing a
doctor of Optometry for evaluation allows the patient an
unbiased assessment of which procedure is indicated. The
doctors of Vision Clinics, Ltd. co-manage with three refractive
surgeons in the greater Cleveland area. Between these three
surgens, all four procedures are represented; but no one
surgeon does all four. Therefore, referral to the proper
surgeon insures the most appropriate procedure will be done.
Our co-management relationship also allows the use of our
records to assist the surgeon in the preparation of the
surgical correction, and all postoperative care is done at one
of our convenient Vision Clinics, Ltd. offices. While current
eye examination data is required, a consultation at no charge
can be done by the doctors of Vision Clinics, Ltd.
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What are some of the more serious complications that have
occurred after LASIK refractive surgery has been performed?
This is obviously one of the most important questions that can
be asked about refractive surgery. Fortunately, most LASIK
procedures are performed with no problems of any kind. It is
important however, that anyone having surgery, especially on
their eyes, be aware of the possible complications, however
rare they may be.
1) Dislodged corneal flap: Because the LASIK procedure involves
making an incision into the cornea, then reflectng that tissue
back to apply the laser, it is possible that the flap created
may come loose and dislodge before healing occurs. It is
important that patients not rub their eyes for at least 24 hrs
following surgery. Clear plastic eye shields can be worn over
the eyes for protection and patients are usually advised to
sleep on their back for at least 1 week. If the flap is
dislodged, it must be lifted, rehydrated and repositioned.
2) Wrinkles in the corneal flap: This can create irregular
astigmatism and reduced vision if the wrinkles are in the
center of the cornea. The flap must be lifted, rehydrated and
repositioned. If the wrinkles are located peripherally, they
may smooth themselves out over 3 to 12 months.
3) Edema in the corneal flap: Swelling of the flap implies that
it is not adhering to the underlying tissue, and the proper
fluid balance is not being maintained. The flap may need to be
lifted, rehydrated and repositioned. In addition, some eye
drops may need to be prescribed to reduce the swelling.
4) Corneal Ulcers and Infiltrates: These complications of
infection (ulceration) and inflammation (infiltration) need to
be treated aggressively. Most times, antibiotics and/or
antiinflammatories will be used.
5) Corneal Epithelial Abrasions: Some types of eye drops used
before LASIK surgery can loosen the corneal epithelium which
may then be abraded (scratched) during the procedure. It is
generally not a problem. If a considerable abrasion occurs, a
contact lens bandage may be placed on the eye for 24 hours to
aid it in healing. Persistent abrasions can lead to red,
uncomfortable eyes with poor vision, an increased risk of
infection, and irregular astigmatism.
6) Debris under the corneal flap: It is very difficult to
complete a procedure without some minor debris getting under
the corneal flap. Most of the particles are normal elements in
the eye like debris found in the tears that bathe the cornea.
Other particles can be metallic flecks or oil-like deposits
from the surgical equipment. Some fibers come from the sponges
used or even from the air in the surgery room.
7) Peripheral haze in the cornea: This is a clouding of the
cornea adjacent to the white part of the eye. This is a
self-limiting finding that is usually of no consequence.
8) Epithelium under the corneal flap: When the incision is made
to create the corneal flap, or when the flap is laid back down,
some cells from the top layer of the cornea (epithelium) may be
trapped under the flap. It is also possible that some of the
epithelial cells may grow in from the edge of the flap during
healing. Because these "displaced" cells do not belong
in the now exposed deeper layers of the cornea, another type of
surgery (PTK) and/or alcohol treatment may be required to
destroy the nests of cells.
9) Increased sensitivity to glare: Approximately 20% of LASIK
patients will experience an increased sensitivity to glare
created by lights at night. While there is no specific
correction for this, most of the individuals describe the
condition similar to the increased sensitivity to glare
resulting from contact lenses at night.
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Amblyopia
When one or both eyes do not correct to 20/20 vision with glasses
or contact lenses. 90% of the time, amblyopia is due to the
eyes not developing properly and could have been prevented by
wearing glasses prior to four years of age. Patching the good
eye and forcing the bad one to see is the first part of therapy
for amblyopia, after which the eyes must be trained to work
together as a team. Dr. Kammer sometimes prescribes contact
lenses for this condition, even in very young children. A
blurred lens is placed in front of the 'good' eye, forcing the
weaker eye, which is also corrected with a contact lens, to
work. Patching is effectively accomplished, and no patch is
required.
Astigmatism
Astigmatism is an optical condition of the eye where the light
is not focused on the back of the eye as a point, but as a
line. In other words, there is more than one point of focus.
This requires a correction that has a 'cylinder' and 'axis' in
it along with the 'sphere'. Most people have some degree of
astigmatism. The important thing to remember is that it is not
unusual and that it is not a disease. However, there are
diseases of the cornea, such as keratoconus, that can cause
large amounts of astigmatism.
Cones
The photoreceptors in the retina responsible for color image
perception.
Crystalline Lens
The small, flexible lens within the eye, that allows variable
focusing power of the eye.
Diopters
A measurement of power in optics. One '1' diopter of plus power
bends light so that it converges (focuses) on a point 1 meter
away. 2 diopters of plus power focuses the light 1/2 meter
away, and is therefore stronger (bends the light more). 3
diopters of plus power focuses the light 1/3 meter away, 4
diopters 1/4 meter, 5 diopters 1/5 meter and so on.
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Farsightedness
See Hyperopia
Hyperopia
Hyperopia, or farsightedness, occurs when the curvature of the
cornea, which causes light to come to a focus within the eye,
is not steeply curved enough, compared to the length of the
eyeball. The image entering the eye focuses behind the retina. Consequently,
objects farther away will appear clearer than those at
near. Young farsighted patients can usually see both
distant and near objects, depending on the severity of their
farsightedness. Unfortunately, their eyes have to work extra
hard to see clear and this usually causes problems with the
ability of their eyes to work together, leading to headaches,
eye strain, reading problems, etc. School screenings
typically will not detect farsightedness.
Lensometer
An instrument that measures the prescription of an ophthalmic
lens.
Myopia
Myopia, or nearsighted, occurs when the curvature of the
cornea, which causes light to come to a focus within the eye,
is too steep compared to the length of the eye. Patients
that are nearsighted can usually find some point in front of
them where their vision is clear. Consequently, near
objects appear clearer than those farther away.
Nearsightedness
See Myopia
O.D.
Stands for Oculus Dexter which is Latin for 'Right Eye'.
O.S .
Stands for Oculus Sinister which is Latin for 'Left Eye'.
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Ophthalmologist
An eye doctor who first receives a medical degree. A residency
at a hospital depending on his specialty follows an internship.
Areas of specialty might be 'cornea', 'retina', 'cataract',
etc. An ophthalmologist specializes in treating medical
conditions related to the eyes.
Optician
An eye care professional that is trained in optics, lenses, and
the fitting of glasses.
Optometrist
An eye doctor who provides vision care by diagnosing and
treating conditions of the eye and visual system. An
Optometrist specializes in correcting visual conditions with
the use of glasses and contact lenses. Also, Optometrists in
Ohio can prescribe medications for the treatment of eye
diseases, perform punctal occlusion for the treatment of severe
dry eye, and remove foreign bodies.
PD
'Pupillary Distance,' or the distance between the pupils. This
is an important measurement because the 'optical center' of an
ophthalmic lens should be set directly in front of the pupil.
Presbyopia
An ocular condition in which the crystalline lens in the eye is
no longer flexible enough to change shape. Consequently,
the focus of light when objects are held at intermediate or
reading distances is not clear. Beginning near the age of 40, a
multifocal lens (bifocal, trifocal or no-line) is prescribed.
Refraction
In an eye doctors office, a refraction is the testing performed
to determine a patients spectacle correction. This is
usually accomplished with the aid of a phoropter, which has
many lenses in it, and by asking the patient which series of
lenses allows them to see better. An objective refraction can
also be done where the doctor can determine the patients
spectacle prescription without asking any questions. While this
is not as precise as the subjective refraction described
above, it is certainly accurate enough for a child or
individual who cannot respond to subjective testing.
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Retina
The lining on the inside surface of the eye, similar to the
film in a camera. This lining contains the photoreceptors (See
Rods and Cones),
which convert light into the electrical signal our brain reads
as vision.
Rods
The photoreceptors in the retina responsible for black and
white image perception.
Sclera
The "white part" of the eye.
20/20 Vision
Notation System
The 20/20 Vision notation system is a crude method of
describing the clarity of vision. It is based on the prediction
as to what a person with "normal" vision should be
able to see from a distance of 20 feet. Therefore, a person
with 20/20 vision is said to have "normal" clarity of
vision. If a person has 20/40 vision for instance, a person
with 20/20 vision could move back to 40 feet and still see what
the 20/40 vision person would see at 20 feet. Legal driving in
most states is 20/40 vision.
* This really is too simplistic of a measure of vision because
so many other factors need to be considered in vision such as
how the eyes function as a team, ocular alignment, color
vision, depth perception and ocular health.
Transmission
This is used in conjunction with coatings, tints, photogrey,
and glass sunglass lenses. It is a measure of the amount of
light that is allowed to pass through the lens into the eye. If
a lens has 100% transmission, then the lens is perfectly clear.
If it allows 50% transmission then 1/2 of the light passes through
into the eye and 50% is absorbed or reflected away. Sunglasses
are defined as being 30% or less transmission of light. Boaters
and skiers should have 15% transmission sunglasses.
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