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Contact Lenses
INTRODUCTION
Contact lenses are miraculous pieces of
plastic that allow you to see without glasses. In most cases they are used
as a substitute for glasses allowing you to dispense with the glasses.
They also may be used to treat certain eye diseases or cosmetically to
change the apparent color of the eyes.
Successful contact lens wear requires a “partnership” between the
fitter (ophthalmologist, optometrist, or optician) and you, the wearer.
The fitter must decide if your eyes are healthy enough to wear contact
lenses, fit the correct lens for your needs, and teach you how to use and
care for the lenses. The fitter should be available and have a routine for
situations if problems develop. You must then follow the instructions,
care and wear the lenses correctly, and return as required for routine and
emergency care.
- Ophthalmologists are doctors who have graduated from a
school of medicine or osteopathy, after which 3-5 years of extra
training was spent studying about the eye examination, diagnosis,
treatment, and surgery plus fitting of contact lenses.
- Optometrists have graduated from a school of optometry
where they trained in eye examinations, fitting of contact lenses,
and, depending on the state licensure, treatment of certain eye
diseases. They do not perform conventional or laser surgery.
- Opticians fit glasses on the prescription of an
ophthalmologist or optometrist. They also, in some states, fit contact
lenses. They do not perform eye exams, diagnose or treat eye disease,
and do not perform surgery.
- Soft and Rigid Gas Permeable (RGP) lenses are available. Each has
specific indications and has a specific wear and care regimen. The older
hard (PMMA) lenses are rarely used today and have risks similar to RGP
lenses.
- Some lenses are meant for daily wear. With daily wear soft lenses,
you wear the lenses for 1 day and discard them. Other soft and some
RGP lenses are worn for a day and removed and cleaned and disinfected
each night. Soft
lenses are usually replaced on a regular basis, which varies for 1
week to 1 month to 3 months to 1 year. RGP lenses may last for years
with regular care.
- Extended wear lenses, usually soft, are worn overnight for 1 week
and replaced every 1-2 weeks. Trying to extend the wear of lenses
beyond the recommended replacement schedule is a false economy and an
invitation to disaster.
- Overnight wear decreases the amount of oxygen available to the eye
and increases the (rare) chance of infection 4 times. Because of this,
some practitioners do not recommend extended wear of contact lenses.
Newer lenses may be safer.
- Problems from contact lenses range from the inability to remove the
lenses (usually after first being fit) to blindness from infections.
Proper fitting, instruction, care, and maintenance will avoid most
problems.
- When being fit with contact lenses, the fitter should provide
information as to what to do in case of a problem. If he or she cannot
manage problems, there should be instructions as to whom you should
call (someone must be available 24 hours a day) and how to proceed.
For example, an optician should have an ophthalmologist or if allowed
to use medications by state law, an optometrist, available for
management of problems.
- Due to the specialization of the eye, this emergency plan is more
satisfactory, and much less expensive, than automatically sending you
to an Emergency Department. Also, some insurance plans may not pay for
Emergency Department visits if the situation could have been handled
in the practitioner’s office.
- After being fit, inability to remove lenses occasionally occurs,
USUALLY THE FIRST NIGHT. With most lenses, it will do no harm to leave
the lenses in until seen by the fitter the next day. Call your fitter
for instructions as to how to proceed.
- The most common reasons for contact lens wearers to seek care is
irritation of the eyes, redness, or blurred vision. These can be caused
by the lenses wearing out or warping, due to a change in the eyes
requiring new lenses, poor fitting of the lenses, or sensitivity to
solutions. These relatively minor inconveniences must be evaluated
because they may signal the onset of corneal ulcers and deeper
infection.
- With the glut of contact lens solutions available, it is important
to use only the solution recommended by the fitter. Some solutions
may be incompatible with certain lenses or may contain components
such as Thimerosal (20% of people are allergic to this), which are not
compatible with the eyes of certain people.
- One major concern, from the wearer's viewpoint, is the danger when
a contact lens slips off the eye. The lens sits on the surface of the
eye and cannot go “back to the brain” because the clear covering of
the eye goes under the eyelid and will keep the lens from going
further back. If the lens cannot be repositioned on the front clear
cornea, it is under the lid and can be easily slid or moved to its
correct position on the cornea (sometimes requiring the help of the
fitter). It will do no harm if it is under the lid for a number of
hours or overnight.
- Redness of the eyes associated with pain, blurred vision, and
sensitivity of the eyes to light is more serious and may signal a
potentially blinding condition, such as a corneal
ulcer due to an infection.
- Abrasions of the front clear window of the eye (corneal
abrasions) usually result from insufficient oxygen reaching the
surface of the eye. It may be due to overwear of the contact lenses or
from lenses that are not tolerated by the eye. These disturbances of
the surface of the eye not only may be very painful, but they may
predispose the eye to a serious, blinding infection.
- Occasionally someone inadvertently soaks his or her lenses in
cleaning solution or soap solution resulting in redness of
the eye with a great deal of pain.
- Makeup can get under a lens and cause irritation or can cause a
greasy film on the lens, making it difficult to see
clearly.
- It is important to keep in mind that any of these eye complaints may
have nothing to do with the contact lenses and may be signs of other
unrelated eye diseases such as infections, cataracts, or glaucoma. The point is that any change in the condition
of the eyes of contact lens wearers must be evaluated for the cause and
possible treatment. If due to the contact lenses or not due to them,
they still must be diagnosed and treated. Opticians do not treat eye
disease. When in doubt, call your fitter for information as to how to
proceed.
Irritation may occur as a result of wornout
lenses, overwear of lenses, poor care of lenses, intolerance to solutions
or infections, or from poor hygiene on the part of the lens wearer.
- Lenses, if worn longer than recommended or in sensitive people, may
develop deposits on the surface of the lenses. These may be quite
irritating.
- A major cause of blinding eye infections is spitting on a contact
lens when no solution is available. This happens when a contact lens
wearer must remove a lens or if a lens falls out of the eye and no
solutions are available. Although tap water may be contaminated, this is
safer than spitting on the lens. The best solution is to have a small
bottle of rewetting solution with you at all times.
- Some people use homemade or non-contact lens saline in an effort to
save money. These solutions may cause severe irritation or blinding
infections and should never be used. Always use the correct contact lens
solution, which was recommended by the fitter. If you want to change
solutions, check with your fitter because some solutions may be
incompatible with certain lenses.
Redness, light sensitivity, pain,
and blurred vision are the main signs and symptoms of eye problems.
Depending on the cause, symptoms vary in intensity. In the more serious
infections, the pupil in the infected (red) eye may be smaller than the
other pupil.
- With a torn or
broken lens or if there is something in
the eye, there is usually a slight feeling of general irritation as
if something is in the eye. There may be associated redness.
- With a poor fitting
lens or a lens that is
old, there may be a slight irritation associated with some blurring
of vision.
- Makeup in the eye or a reaction to solutions can vary from slight to
marked redness with slight to marked pain.
- Corneal abrasions (“scratches”) are usually quite painful, with or
without the lens in the eye, and are associated with light sensitivity
with or without blurring of vision.
- Infections are a major concern because they may cause severe eye
damage.
- Simple pinkeye is usually associated with redness, clear or
mucus discharge and matting of the eyelids. Vision is usually clear.
- Of more concern are infections of the cornea (front, clear window)
of the eye. These show up by marked redness, sensitivity to light,
blurred vision, and a variable degree of pain. Occasionally it is
possible for the lens wearer to see the infection, which may show up,
as a white spot on the surface of the eye.
- When a lens “slips” off the surface of the eye, there is immediate
blurred vision, which may, or may not, be associated with a sensation of
something under the upper eyelid.
Home Care
- In case of irritation, pain, blurred vision, redness, or light
sensitivity, immediately remove your lenses and re-evaluate the
situation.
- Because you should not wear your lenses with these problems, it is
essential that every person who wears contact lenses have an
up-to-date backup pair of glasses for these times. With well-fitting
lenses, these glasses would only be used in the case of an emergency,
thereby enabling you to function in driving or at work.
- Examine the lens for defects. In the case of a torn soft lens or a
cracked gas-permeable lens, there should be immediate relief once you
remove it.
- In case of soap or cleaning solution in your case, irrigate your
eyes with your lens rinsing solution or tap water. Either discard the
lenses or rinse them off multiple times in the storage solution to rid
the lens of the soap.
- When the irritation is from something
blowing into the eye, remove the lens and try to evert the lid to
look for a foreign body, which is usually located near the center of the
lid, just a little back from the margin. The foreign body may be removed
with a cotton-tipped applicator or a rolled up piece of facial tissue.
There is usually immediate relief of the discomfort.
- If eyedrops are prescribed for an infection or other condition,
check with your doctor to see if it is all right to use the drops
without removing the lenses. Some drops will damage certain
lenses.
- To instill drops, hold your head back and squeeze 1 drop out of
the bottle. Only 1 drop at a time is used, because a second drop would
run out and waste money. Close your eye for about 30 seconds after
instilling drops to decrease the absorption of the drop into the
system and, in doing so, decrease the chance of allergic or other
reactions. If you find it difficult to use drops, simply hold your
head back and place 1 or 2 drops on the closed lids. When you open the
eye, a drop will flow in.
Call the doctor (or your
fitter if he or she is allowed to treat eye problems) anytime you have a
question of any type or any time there is redness, blurred vision, pain,
and light sensitivity. Normally you should be seen that day. Call the
doctor (or fitter) anytime that there is a question about your eyes or
contacts.
Most ophthalmologists are available 24 hours a day via their answering
service. If your doctor is not available, speak to the doctor on call.
With optometrists and opticians, there may not be 24-hour availability,
and you should ask about the routine in case a problem should develop
outside of regular office or store hours. Many will have an
ophthalmologist to whom they refer medical problems. Others may tell you
to go to a hospital's Emergency Department.
- Prior to going to the Emergency Department for contact lens
problems, you should be familiar with the terms of your insurance
contract. Because many of these problems are not emergencies, some
insurance plans will not pay your bill and shift it to you, the patient.
Also, many emergency physicians may not be very familiar with eye
problems and will see you and then refer you to an ophthalmologist on
call, requiring an extra visit.
It should be very rare
that you must go to a hospital for contact lens problems. Hospital
Emergency Departments should be used for emergencies, not for convenience.
Because of the specialized nature of eye examination equipment, contact
lens problems are usually handled best in eye specialists' offices. If the
Emergency Department has the necessary eye equipment, an eye specialist
may see patients in the Emergency Department after hours.
If there is no specialist available, or if your contact lens fitter
does not manage contact lens problems, you may have to go to an Emergency
Department when there is significant pain, blurred vision, and redness of
the eye. Try to contact someone during the day, rather than waiting until
evening or late at night before seeking help. If your fitter does not
manage complications and problems, you may want to call your local
Emergency Department first to ask if the staff handles contact lens
problems.
PHYSICIAN DIAGNOSIS
Diagnosis and management of
contact lens problems entail the taking of a history and an examination of
the eye.
- You will be asked questions about what is bothering you. It is
important to know the type of contact lenses being worn (soft, gas
permeable, or the older hard lenses), what type of care regimen you use
(cleaning, disinfecting, and rinsing solutions), what type of wear
(daily disposable, weekly overnight wear, or daily wear), and how often
the lenses are replaced (daily, weekly, monthly, quarterly, or yearly).
It is important to know how long you have been bothered and if there is
light sensitivity, redness, and blurred vision. Is it getting better or
worse?
- The examination of
the eye involves checking the vision (with your glasses because you
have removed the lenses). If the vision cannot be corrected, the doctor
would be concerned as to the presence of a serious problem. The examiner
will look with varying types of lights, starting with a flashlight type
of instrument, followed by an exam with a slit lamp—basically a
microscope with high magnification and different color lights. A dye,
fluorescein, is placed on the eye. This makes abrasions and ulcers show
up clearly.
- With apparently severe infections, cultures of the eye are taken and
sent to the laboratory for evaluation and guidance as to what specific
antibiotic drop may be required.
PHYSICIAN TREATMENT
Treatment ranges from stopping
the lenses for a short time to intensive antibiotic treatment of
infections. It may be necessary to wear your glasses for a variable period
of time. If only 1 eye is affected, there is nothing wrong with wearing
only 1 lens. This is tolerated well by most people. There is no harm if
only 1 lens is worn.
- If the lens is worn out or torn, it will be replaced. With frequent
replacement lens wear, you usually have extra lenses at home and can
easily replace the lens yourself.
- If a solution incompatibility is suspected, the solutions and care
regimen will be changed.
- If the lens is not fitting well, the wear will be discontinued. It
may be necessary to refit you with new lenses, which may be better
tolerated or may provide better vision.
- With infections, antibiotic eyedrops will be used (pills are rarely
used because the drops are so much more effective). The doctor uses the
drop, which he or she feels will be most effective. With corneal
infections, a culture of the infection may be taken in order to decide
upon the best antibiotic. Drops may be used every hour, and you might
have to be seen every day with the more serious infections.
- On rare occasions, surgical management of the infection may be
necessary. The ultimate is the need to administer antibiotics via
injections in the eye or a corneal transplant.
In the vast majority of cases, the contact
lens problems are managed with no permanent damage. You can return to
normal contact lens care.
In the case of serious corneal infections, blindness and loss of the
eye may occur. This is rare.
PREVENTION
Correct fitting, using the correct care
regimen, and periodic follow-up by the fitter will avoid most problems.
- Cleanliness is an essential. Do not handle contact lenses without
first washing your hands. Contact lens
cases must be washed every day and should be discarded and replaced
periodically because they may serve as a culture medium for bacteria.
- Any contact lens wearer must be reliable and follow the general
rules of good hygiene. The wearer must be motivated or else he or she
will not follow the instructions for avoidance of problems. For this
reason, some fitters will not fit children. Children must be evaluated
on a case-by-case basis. There must be sufficient maturity and
intelligence to wear contact lenses. In young children, younger than age
8-9 years, lenses are usually fit for medical reasons. The parents
assume the responsibility for the correct care and wearing of the
lenses. For cosmetic purposes, motivated, reliable children may be
easily fit for lenses at the age of 8 or 9 years.
- Different types of lenses have individual care routines. In general,
care of lenses involves rinsing of the lenses upon removal, cleaning the
lenses, and storing them in a disinfecting solution. Under no
circumstances should homemade or non-contact lens saline or solutions be
used. Use the solutions that are recommended.
- The lenses should be worn and discarded as directed. If lenses are
to be replaced on a daily, weekly, or other basis, it is a false
economy and dangerous to try to extend the lenses by replacing them
less often.
- Probably the safest way to wear lenses is to wear them on a daily
basis and discard them every day. This avoids the use of solutions and
decreases handling. However, it is slightly more expensive, and daily
disposable lenses are not available in all prescriptions.
- Overnight wear of contact lenses is available for certain
prescriptions. This, although approved by the FDA, is not felt to be
safe by many fitters due to the increased rate of infections with
extended wear.
- Most complications may be eliminated by conscientious wear and care
by the wearer and instructions and follow-up by the fitter.
- It is essential to be examined by your ophthalmologist or
optometrist at least once a year and more often if extended wear
lenses are worn. Every exam should, at a minimum, include a history as
to how the lenses are cared for and to find out if there are any
problems. The vision should be checked with the contact lenses, and
the lenses should be observed on the eye with the slit lamp. This
would also include an evaluation of the vision with glasses after
removing the lenses.
- The exam will also include a measurement of the shape of the
cornea. No distortion or changes should be present. The cornea, as
well as the rest of the eye, should be evaluated, along with an
evaluation for the possible presence of any eye diseases such as
glaucoma or cataracts.
FOLLOW-UP
All contact lens wearers should have an
annual follow-up exam. This will give the fitter a chance to review the
care, wearing, and fit of the lenses. Problems or potential problems can
be found before they interfere with vision.
- People wearing extended wear lenses should be seen every 3-6
months.
- Fitting of lenses involves a complete eye examination with
measurements of the cornea and selection of an appropriate lens. The
fitting is not complete until follow-up evaluations confirm the correct
fitting of the lens. After this, in most states, fitters must give the
lens prescription to the wearer if he or she desires it. Some people
then will order their lenses by mail order or through local stores. If
this is done, it is essential to make sure that the lens received is
exactly the same as the lens that was fit and dispensed. Although people
use mail order due to an expectation of a lower price, check with your
fitter. The fitter usually will meet or beat the price of the mail order
companies. If lenses are purchased elsewhere than from the fitter, be
sure to have follow-up exams at the intervals recommended by the
fitter.
- For more information on contact lenses, check organizations and Web
sites:
REFEERENCES:
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