EYE EXAMINATION PROCEDURES
Eyeglass Examinations: The
standard examination procedure for a patient who wants to wear eyeglasses
includes at least the following:
history; reason for examination, patient medical and eye history, current
of monocular (one eye) and binocular (both eyes) visual acuities at far
and near, with and without present correction
responses (Neurological Integrity)
examination findings (Biomicroscopy)
examination findings (Ophthalmoscopy)
prescription (when applicable)
testing at far and near
Contact lens examination: Requirements for patients who wish to wear contact lenses
include all of the standard eyeglass examination procedures as well as
lens testing (when applicable)
external examination (biomicroscopy) with and without contact lenses
of follow-up visits to ensure compliance with maintenance and wearing
Providers generally assess
higher charges for contact lens examinations than for eyeglass examinations.
Some benefit plans may require members to pay the difference between the
usual and customary price for an eyeglass examination and the usual and
customary price for a contact lens examination.
Dilation: The enlargement of the pupil diameter,
which allows the doctor to observe the internal eye more completely. It
is not always part of a provider's standard examination procedure, but
providers may perform dilation if any of the following conditions exist:
(nearsightedness) over 6 diopters
(high blood pressure)
changes in vision
or personal health history that predicts future ocular complications
law requiring dilation
Disease detection: During the course of an examination, an optometrist
or ophthalmologist may detect abnormalities in the eye that are symptomatic
of certain diseases that require treatment from another health care provider,
such as diabetes or hypertension. In this case, the member will be referred
to the appropriate medical provider based on their health plan.
Prescription: Prescriptions are often written following
an examination to correct one of the following conditions:
- Myopia: ("nearsightedness") A
condition in which light refracted into the eye focuses at a point in
front of the retina.
Myopic individuals can see objects clearly at near and have trouble seeing
at far. Myopia is correctable with eyeglasses or contact lenses. Myopic
correcting lenses are concave, or thinner in the center than on the edge.
- Hyperopia: ("farsightedness")
A condition in which light refracted into the eye focuses at a point
behind the retina. Hyperopic
individuals can see objects clearly at far and have trouble seeing at
near. Hyperopia is correctable with eyeglasses or contact lenses. Hyperopic
correcting lenses are convex, or thicker in the center than on the edge.
- Presbyopia: The loss of focus ability due to the natural aging
process. It is correctable with bifocal or trifocal lenses that reduce
the need for the eye to focus when changing from far to near vision.
- Astigmatism: A condition in which an asymmetric cornea results in different visual
irregularities in different parts of the eye. It is correctable with
eyeglass lenses that are ground to a different thickness and curvature.
Toric soft contact lenses or rigid contact lenses can also correct some
cases of astigmatism.
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TYPES OF PROVIDERS
medical doctor (MD) or osteopath (DO) who specializes in the treatment
of the eye and visual system. In addition to providing routine eye care,
ophthalmologists can diagnose and treat eye disease using medical or surgical
eyecare professional who has completed four years of optometry school after
graduating from college. Optometrists specialize in examination, diagnosis,
and treatment of conditions of the visual system, including prescribing
and fitting eyeglasses and contact lenses. Optometrists are not authorized
to use surgical techniques to treat eye disease.
optician: Helps patients with the selection of frames, and
also measures, adjusts, and fits eyewear using prescriptions supplied
by an optometrist or ophthalmologist.
optician: Manufactures eyewear using prescriptions supplied
by an optometrist or ophthalmologist.
technician: Performs the same duties as a dispensing optician,
but has also had two years of formal training or has passed the National
Optometric Registration Exam for technicians.
Dispensing location: Optical facilities that
have the capability to dispense eyewear. Some dispensing locations
have on-site manufacturing capabilities, but the majority of dispensing
locations use offsite eyewear manufacturing
DPA certification: Diagnostic
pharmaceutical agent (DPA) certification is granted to optometrists who
have demonstrated capability to diagnose eye disease. State licensing agencies
serve as the certifying body for DPA certification.
TPA certification: Therapeutic pharmaceutical agent (TPA)
certification is granted to optometrists who have demonstrated capability
to diagnose and treat eye disease. In addition, TPA certified optometrists
can prescribe certain medications to treat eye disease. State licensing
agencies serve as the certifying body for TPA certification.
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TYPES OF EYEGLASS LENSES
Single vision lenses: Uncoated, plastic lenses with a single prescription
that corrects myopia, hyperopia, or astigmatism.
Standard bifocal lenses: Uncoated, plastic lenses that correct both
for distance and near vision in individuals with presbyopia. The top of
the lens corrects for distance vision. In the lower part of the lens, there
is a visible semicircle ground into the lens that corrects for near vision.
Trifocal lenses: Uncoated, plastic lenses that correct for
vision at three distances. The top of the lens corrects for distance vision.
In the lower part of the lens, there is a visible semicircle ground into
the lens that corrects for near vision. Just above this semicircle is an
additional lens segment that corrects for distances of about an arm's length
Lenticular lenses: Designed to treat eye conditions that are
more serious than simply myopia, hyperopia, presbyopia, or astigmatism.
They are often prescribed after cataract surgery for patients without intraocular
Progressive lenses: Commonly called "no-line bifocals",
progressive lenses are bifocal or trifocal lenses that have an invisible
corridor of increasing power that leads from the distance portion of the
lens down to the reading portion.
Polycarbonate lenses: Made of a material similar to standard
plastic, but are lighter in weight and thinner than uncoated plastic lenses.
They offer protection from surface abrasions like scratch resistant coated
plastic lenses, and they do not shatter like glass or standard plastic
Photochromic lenses: Light sensitive glass lenses. The glass
contains silver halide crystals that darken when exposed to ultraviolet
(UV) light and become clear when removed from the light. In their darkened
state, photochromic lenses offer protection from potentially damaging UV
Transition lenses: Light sensitive plastic lenses, which makes
them lighter in weight than photochromic glass lenses. They become darker
when exposed to ultraviolet light and lighten when removed from the light.
Transition lenses resist UV radiation both when light and dark, and the
lenses are scratch resistant.
Scratch resistant coated lenses: Offers
protection from most surface abrasions. The coating is included as a part
of polycarbonate lenses, but available as an option that is applied to
the surface of standard plastic lenses after the lenses are ground.
Glass lenses: Generally heavier than plastic lenses and
resist scratching better than uncoated plastic lenses.
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TYPES OF CONTACT LENSES
Daily wear contact lenses: Can
be soft or rigid contact lenses made of different types of plastic, depending
on the specific type of lens.
Daily wear lenses
are to be worn for periods of less than 24 hours at a time, and should be
removed each night before the wearer goes to sleep. Lenses generally need
to be replaced annually or biannually.
Extended wear contact lenses: Usually
soft contact lenses, but are designed to be worn for 24 hours or more at
a time. Some lenses are FDA approved for up to 30 days of continuous wear,
but most doctors recommend removing and cleaning the lenses at least weekly.
Extended wear lenses have replacement schedules that vary significantly
by the specific type of lens and length of continuous wear.
Disposable contact lenses: Soft contact lenses, either daily wear
or extended wear, that are replaced on a 7 to 30 day cycle. Wearers generally
purchase a supply of disposable lenses that will last six months to one
Hard contact lenses: These are made from a rigid plastic resin,
polymethylemethacrylate (PMMA). The lenses are more durable and easier
to handle than soft contact lenses, but many people may find them uncomfortable.
PMMA does not absorb water, and does not allow for the transmission of
oxygen through the lens to the eye. Hard contact lenses should be removed
Rigid gas permeable contact lenses: (RGP) These contact lenses are made of
a non-absorbent material that is oxygen permeable. RGP lenses are durable
and easy to handle like hard contact lenses, but more comfortable to wear,
though usually not as comfortable as soft contact lenses. Most RGP lenses
are used for daily wear, but some lenses can be worn for extended periods
Medically necessary contact lenses: Following certain surgeries, soft contact
lenses are sometimes prescribed to act as a replacement for the front covering
of the eye that has been removed or disturbed. These contact lens prescriptions
are medically necessary, and are generally addressed differently than elective
contact lenses in managed vision care policies. Medically necessary contact
lenses can also be prescribed for the treatment of certain eye diseases,
Toric lenses: Either hard or soft contact lenses used
to treat astigmatism, which cannot be corrected with traditional spherical
Tinted contact lenses: Many soft and disposable contact lenses
have a visibility tint, usually bluish, that makes them easier to see.
This visibility tint makes the lenses easier to handle and easier to find
if the wearer drops them. There is generally no additional charge for lenses
with a visibility tint. Contact lenses can also be tinted to change or
enhance the color of the wearer's eye. The lenses are generally made with
a clear center so that the wearer's perception of color is not affected.
Since these lenses are more complicated to manufacture, they are generally
more expensive than clear contact lenses.
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LASER VISION CORRECTION TERMS
Lasik: Laser in-situ keratomileuis (Lasik) is a laser refractive
procedure in which a portion of the outermost layer of the eye is temporarily
pulled away to allow a laser beam to make direct contact with the stroma
of the cornea. The laser beam is used to reshape the cornea so that it
focuses light properly into the eye. The outer layer of the eye is then
replaced. Recovery time after a Lasik procedure is usually very short,
often a matter of hours, and patient satisfaction with the procedure is
very high. The procedure is nearly painless, and it can be used to treat
myopia, hyperopia, and astigmatism. Lasik was introduced in the mid 1990's,
and is now the most commonly performed laser vision correction procedure.
PRK: Photorefractive keratectomy (PRK) was one
of the first laser refractive surgery procedures performed to correct vision
defects. In PRK, the outermost layer of the eye is removed, and then a
laser beam is used to reshape the cornea. PRK can be used to correct myopia,
hyperopia, and astigmatism, and results are fairly predictable. The removal
of the outermost layer of the eye can result in significant discomfort,
long recovery time, and the need for steroid drops to reduce inflammation
in many patients. PRK was introduced in the early 1990's.
RK: Radial keratotomy (RK) was introduced in
the 1980's as a surgical technique to correct myopia. RK involves surgical
scarring of the peripheral cornea to change the curvature of the cornea.
Small incisions are made at even intervals around the surface of the eye.
As the incisions heal, scar tissue develops and causes the cornea to reflect
light at different angles. RK outcomes are often unpredictable and rely
heavily on the individual surgeon performing the procedure. It also introduces
the possibility for serious eye damage and compromises the integrity of
the eye. Since the introduction of the laser refractive procedures, RK
has rarely been performed in the United States.
AK: Astigmatic keratotomy (AK) is a variation
of RK that corrects astigmatism. In AK, incisions are made in the eye at
angles instead of at even intervals. AK, like RK, is rarely performed in
the United States due to the significant potential for complications and
the introduction of laser refractive procedures.
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