Myopia (Nearsightedness)
A very common visual condition present to some degree is nearly one in three individuals
in the United States. Myopia results from the eye being too long, the cornea being
too steep or a combination of the two. This causes light entering the eye to be
focused in front of the retina resulting in blurred vision. As the name implies,
nearsighted people see well at near but can’t see clearly at distance. This condition
can be corrected with glasses, contact lenses, lens implantation (see cataract surgery)
or refractive surgery (see LASIK and ASA).
Hyperopia (Farsightedness)
A visual condition in which the eyeball is too short or the cornea is too flat.
These imperfections cause light entering the eye to be focused behind the retina,
resulting in blurred vision. Hyperopia causes difficulty focusing on near objects,
and when severe, can also lead to difficulty focusing in the distance. This condition
can be corrected with glasses, contact lenses, lens implantation (see cataract surgery),
or occasionally with refractive surgery (see LASIK and ASA).
Astigmatism
An irregularity of the cornea (the clear dome of tissue over the colored part of
your eye) that causes blurred vision. There can also be irregularity to the human
lens, that causes astigmatism, but this is much less common. This irregularity causes
images to be improperly focused and blurred at all distances.
The specific cause of astigmatism is unknown, but there is often a hereditary component.
There are also medical conditions such as Keratoconus and corneal scarring that
can also cause astigmatism.
Treatments for astigmatism includes glasses, contact lenses, lens implants and refractive
surgery (see LASIK and ASA).
Conjuctivitis
Inflammation of the conjunctiva, the transparent layer of tissue over the white
part of the eye and lining the inner aspect of the lids. There are multiple causes
of conjunctivitis including allergies, infection and chemical toxicity. Treatment
depends on the offending agent and will be determined by your doctor. Only viral
conjunctivitis, “pink eye” is contagious, but good hygiene including frequent hand
washing should be practiced in all cases of conjunctivitis.
Presbyopia
The hardening of the crystalline lens that results in the diminished ability to
“accommodate” i.e. change focus in order to see near objects. This is a progressive
process that starts early in life but typically doesn’t noticeably affect the vision
until the early to mid forties. This is when people begin to need reading glasses
or bifocals. When individuals become presbyopic, this is actually the first sign
of a developing cataract. The most common type of cataract is a “nuclear sclerotic”
cataract, which literally means central hardening. As mentioned above, the treatment
for presbyopia is the use of reading glasses, or bifocals. Also, bifocal contact
lenses and multifocal intraocular lenses can also be used to address this problem.
Blepharitis
Inflammation of the eyelids with associated burning, itching, redness and “dandruff-like”
flakes on the lashes. Usually caused by staphylococcus aureus a common bacteria
found on the lids. Blepharitis is not contagious and is usually treated with lid
hygiene and antibiotics.
Cataracts
An opacification of the crystalline lens. The crystalline lens lies behind the iris,
the colored part of the eye, and is responsible for focusing incoming visual images
on the retina. Cataracts typically happen later in life, but can occur at any age.
Causes of cataracts include trauma, diabetes, smoking, alcohol, drugs, ultraviolet
radiation, and nutritional deficiencies. When cataracts impair a patient’s ability
to perform day-to-day tasks, such as driving at night, surgery may be necessary.
Cataracts are removed by a surgical procedure called phacoemulsification in which
high frequency ultrasound is used to dissolve the cataract, which is then removed
by suction. The procedure itself takes approximately 7-10 minutes per eye. Cataract
surgery is the most common and most successful surgery performed in America today.
(“Eyemagination” video here).
Dry Eyes
A condition in which there are insufficient tears to lubricate the surface of the
eye. This is a result of either decreased tear production or increased tear film
evaporation. Natural tears nourish the surface of the eye and are necessary to maintain
the health of the ocular surface and to maintain clear vision. Development of dry
eyes is a natural part of the aging process and is more common in women. This condition
can be exacerbated by certain medications such as antihistamines or decongestants
and can be more common in people with certain medical conditions like rheumatoid
arthritis, thyroid disease or diabetes. Dry eyes can also be intensified by refractive
surgeries such as LASIK. Numerous treatment options for dry eye are available, including:
eye drops to replace or stimulate tear production, punctual plugs to increase tear
retention on the surface of the eye, and management of eyelid disorders contributing
to dry eyes.
Pinguecula
A yellowish-white growth on the surface of the eye, usually on either side of the
cornea (clear front part of the eye). A pinguecula is a benign overgrowth and degeneration
of the normal conjunctival tissue on the eye. The normal conjunctiva is the clear
membrane that covers the white part of the eye. Pingueculae are most commonly seen
in people who reside in tropical climates and areas of higher ultraviolet (UV) exposure.
Pinguecula usually do not require treatment, unless they become inflamed or are
cosmetically undesirable.
Pterygium
A wing-shaped, benign growth on the surface of the eye, extending from the conjunctiva
onto the cornea. Pterygia are thought to be related to excessive exposure to ultraviolet
light, wind and dust. Pterygia are more common in men and in people residing near
the equator and in windy locations. Symptoms associated with pterygia include persistent
redness, inflammation, foreign body sensation and dry or itchy eyes. Visual distortion
can occur due to corneal astigmatism induced by growth of the pterygium onto the
cornea. Treatment options include eye drops to relieve redness and irritation or
surgery to remove the growth and prevent further distortion of the vision.
Diabetic Retinopathy
Damage to the retina, the light-sensing lining of the back of the eye, caused by
complications of diabetes. Poorly controlled or long standing diabetes causes weakness
in the walls of the retinal blood vessels causing them to leak. This results in
a reduction in available oxygen, retinal damage, and potentially permanent vision
loss. Individuals with diabetes should have a comprehensive, dilated eye examination
at least yearly to screen for these ocular complications. If retinopathy is detected
early, it is often treatable and manageable. When necessary, treatment with medication,
laser or surgery can halt or potentially reverse the damage from diabetes. If untreated,
diabetic retinopathy can result in loss of part or all of the vision.
Lasik
A form of laser vision correction that improves vision by altering the shape of
the front surface of the eye. Laser-Assisted In-situ keratomileusis, or LASIK, uses
an excimer laser to change the shape of the cornea, allowing for good focus with
little or no help from corrective lenses. LASIK surgery is unique in that it is
performed under a physician created flap of tissue that is replaced at the conclusion
of the procedure. This allows for rapid visual recovery with little to no discomfort.
However, the flap created during the procedure is vulnerable to shifting and/or
wrinkling for several days or even weeks after the procedure, so caution during
this time period is imperative.
ASA(Advanced Surface Ablation)
A method of laser vision correction that corrects vision in much the same way as
LASIK, but does not require the creation of a flap. ASA is a modified and dramatically
improved version of PRK or Photorefractive Keratectomy, a procedure performed in
the 1980’s. ASA does not involve the process of creating a flap, but instead requires
the removal of the outer most layer of the cornea called the epithelium. As a result,
it may take several days to see well and some discomfort may be experienced during
this period. The major advantage with ASA is that there is no flap and therefore
both intra-operative and post-operative complications are extremely rare. Even though
the sharpest visual results may take time to be realized, the safety and simplicity
of the procedure have made ASA extremely popular amongst both physician and patient.
Additionally, for patients with previous corneal surgery, thin corneas, or unusually
shaped corneas, ASA is often mandatory.
Keratoconus
A disease of the Cornea that affects its shape. Typically the cornea, which is the
clear tissue on the outermost surface of the eye, is a spherical shape. For people
with Keratoconus it bulges forward in a cone like shape and disrupts the normal
focus of light. Treatments for Keratoconus include glasses, contact lenses, Intacs
inserts, and corneal transplantation. A new treatment involving the vitamin riboflavin
is awaiting FDA clearance and offers very promising results in stabilizing vision.
Glaucoma
A broad term that describes a condition that results in decreased blood flow to
the optic nerve. The optic nerve relays visual information from the eye to the brain.
When the nerve is damaged by glaucoma, it results in a loss of peripheral vision
first, followed by central vision if it is not treated. The most common form of
glaucoma happens very slowly and in most cases is painless. It can be monitored
with a variety of tests and treated, in most cases, with eye drops to prevent progression.
A rare type of glaucoma called, “acute”, or “narrow angle”, requires immediate treatment
with laser and medical therapy to avoid visual loss. With appropriate treatment
and appropriately scheduled follow-ups, most of the visually damaging effects of
glaucoma can be prevented.
Macular Degeneration
Much like a camera, the eye focuses light onto a film so that the picture may be
relayed to the brain. In the eye, the film is referred to as the retina, and the
central area on which the picture is displayed, is called the macula. In the disease,
macular degeneration, the central area of vision suffers age related changes and
vision becomes distorted and irregular. Initial treatments involve specific nutritional
supplements and careful monitoring of symptoms with a device that measures distortion,
called an Amsler Grid. This form of management is most common for the “dry” form
of the disease. If leaking or bleeding occurs in the areas of degeneration it is
called “wet”, and may benefit from medical or surgical treatments.