Age Related Eye Disorders

Presbyopia 

An unwelcome harbinger of middle age, presbyopia is part of the natural process of growing old.  Usually beginning by about the age of 45, presbyopia is the inability to focus the eyes on near objects and it gets progressively worse until about the age of 65.  Presbyopia may be first noticed when it becomes necessary to hold objects farther away in order to see them clearly.  The term presbyopia comes from the Greek presby meaning ‘old’ and opia pertaining to ‘the eyes’.  It is caused by the gradual loss of elasticity of the lens necessary to change its shape in order to focus.  Presbyopia affects everyone and while there is no cure, it can be corrected with glasses. 

Cataracts 

A cataract is a clouding of the normally clear lens of the eye caused by a buildup of protein.  As they grow, cataracts eventually prevent a light image from reaching the retina resulting in diminished vision.  Most cataracts are related to aging and affect more than half of individuals by the age of 80.  Cataracts develop slowly over time and can affect one or both eyes.  They may begin to develop in middle age, but in the early stages of cataract development you may not be aware that you have one.  Symptoms of a cataract can included blurred vision, faded colors and diminished night vision.  Diabetes, smoking, alcohol use and exposure to sunlight may put you at increased risk for developing a cataract.  Cataracts can also develop as a result of an eye injury or after eye surgery or can be present at birth (congenital cataracts).  Cataracts are diagnosed during a full eye examination by an ophthalmologist or optometrist.  Vision with a cataract may be improved with eyeglasses and better lighting, but when they begin to interfere with the activities of daily life, surgery may be necessary.  The procedure is usually performed on an outpatient basis by an ophthalmologist and most often consists of removal of the clouded lens and replacement with a clear, artificial one.  One of my elderly patients told me that after her cataract surgery she was shocked when she looked in the mirror and saw how many wrinkles she had developed since her vision had become affected! 

Glaucoma 

Glaucoma is an increased pressure in the eye which can damage the optic nerve that transmits images to the brain.  It is the second most common cause of blindness in the U.S. after cataracts.  The anterior chamber of the eye behind the colored iris is filled with a fluid called the aqueous humor.  New fluid is continually being formed and the excess is normally drained through channels in the angle between the iris and the cornea, keeping pressure in balance.  Anything that obstructs these channels can cause the intraocular pressure to go up resulting in glaucoma. 

There are four types of glaucoma: 

(1) Open-angle or chronic glaucoma is the most common type and tends to run in families.  There may be no symptoms until severe damage has already been done.  Most patients can be successfully treated with eye drops. 

(2) Angle-closure or acute glaucoma occurs when there is an abrupt closure of the channels which drain the aqueous humor.  There may be sudden, severe pain in one eye, redness and decreased vision.  This is a medical emergency and drops or other medication is used to decrease the pressure and prevent blindness.  Occasionally an operation called an iridotomy is necessary.

(3) Congenital glaucoma is present at birth, is usually inherited and is generally treated with surgery. 

(4) Secondary glaucoma is caused by medications, such as long term steroid use, trauma or other eye diseases.  Treatment depends on the cause.

Glaucoma is diagnosed by an eye care professional, generally by testing the eye pressure.  Everyone should have a complete eye examination by age 40 or sooner if you have a family history of glaucoma. 

Macular Degeneration 

Age-related macular degeneration (AMD) is a condition that affects older individuals, as its name implies, and is one of the most common causes of visual impairment and blindness in those over 50 years old.  It results from damage to the center of the retina (macula) which causes loss of vision in the center of one’s field of vision.  Because the area of the macula is important for providing detailed, sharp vision, patients with AMD have difficulty reading, watching television and recognizing faces.  AMD does not cause complete blindness and most patients can compensate to some extent by taking advantage of their peripheral vision.  There are two basic types of AMD, the more severe wet or exudative form which accounts for 10% of cases and the more common dry or nonexudative form.  There is no treatment for the dry form which is caused by accumulation of cellular debris beneath the retina.  The abnormal growth of blood vessels which characterizes the wet form can be treated with laser coagulation and medication to slow the growth of the blood vessels.  Both types can cause retinal detachment.  While there is no pain related to AMD, symptoms include blurred vision, missing areas of vision and distorted vision where straight lines appear wavy.  Caucasians, those with a family history and smokers have an increased risk of developing AMD.  Macular degeneration should be diagnosed and managed by an ophthalmologist. 

Diabetic Retinopathy 

Just as both type 1 and type 2 diabetes contribute to damage to the medium and large blood vessels of the heart and brain (macroangiopathy), they also cause damage to the small blood vessels and capillaries of the kidneys, eyes and nerves (microangiopathy).  In the case of the eyes, diabetes affects the blood vessels of the retina, the light sensitive tissue lining the back inner surface of the eye.  The damage develops slowly over time and patients may not notice it at first.  Eventually, however, it will cause loss of vision and can lead to blindness.  Diabetic retinopathy will be more severe in those who have had diabetes longer, or have a more severe case or have poorly controlled diabetes.  Almost 80% of patients with diabetes for ten years or more will have manifestations of diabetic retinopathy.  In addition to carefully controlling their diabetes under the supervision of a health care provider, it is imperative that all patients with diabetes be followed by an ophthalmologist, refrain from smoking and control blood pressure and cholesterol levels.  These measures may help to slow the progression of diabetic retinopathy.  An ophthalmologist can diagnose the early stage of diabetic retinopathy, known as the nonproliferative form, by identifying blocked or dilated blood vessels in the retina during an eye examination.  At this stage no treatment may be necessary.  An ophthalmologist will be able to identify progression to the more severe stage of diabetic retinopathy, known as the proliferative form, where new blood vessels begin to form (neovascularization) which can bleed and cause scarring on the retina.  At this stage he may begin treatment with a procedure called laser photocoagulation to stop the blood vessels from leaking or to obliterate abnormal ones.  With the increasing incidence of diabetes due to changes in lifestyle such as diet and activity levels, diabetic retinopathy is sure to remain a major cause of visual impairment throughout the world.  Its economic and personal impact will be all the more significant because it affects patients in their middle years, the years which for most individuals are their most productive.