A cataract is a clouding of the crystalline lens (clear tissue behind the
pupil) that causes a gradual loss of vision. When the lens becomes opaque, light
is unable to reach the retina, resulting in blurred vision. Cataracts are
variously classified according to cause (aging, first trimester rubella
infection, myotonic dystrophy, Down syndrome, trauma, radiation), location
(nuclear, cortical, subcapsular), severity (immature, mature, hypermature), and
age of onset (congenital, juvenile, adult, age-related). Approximately one
million cataract surgeries are performed each year in the United States, while 5
to 10 million individuals annually are disabled as a result of
Aging is the most common cause of cataracts; in fact, most patients over 50
years of age demonstrate cataractous changes. However cataracts may also be
congenital, hereditary, or associated with systemic, metabolic, or ocular
diseases, trauma, radiation, maternal infection during pregnancy, electrical
injuries, and drug use.
- Age over 50 years
- Genetic diseases (e.g., myotonic dystrophy, neurofibromatosis type 2,
Lowe syndrome, Down syndrome)
- Drug therapy (e.g., miotics, steroids, phenothiazines)
- Maternal infection (e.g., rubella, cytomegalovirus), drug ingestion,
or radiation therapy during pregnancy
- Metabolic disorders (e.g., diabetes mellitus, galactosemia,
- Ocular disorders (e.g., glaucoma, uveitis, retinal detachment,
- High-voltage electrical
|Signs and Symptoms|
- Decreased or blurred vision (often described as a "fog")
- Double vision
- Colored halo around lights
- Increased refractive power of lens, allowing patients to read without
glasses (i.e., second sight)
- Brown spots in the visual
There are over 200 conditions (i.e., syndromes, diseases) associated with
cataract formation. Other corneal or retinal lesions are most often ruled out in
a diagnosis of cataracts.
Physical examination is usually not helpful in determining the cause of
cataracts. Lens opacity can be observed visually, especially mature cataracts,
or by ophthalmoscopic or slit-lamp examination.
Laboratory tests almost never suggest the presence or cause of
Ophthalmoscopic examination distinguishes the type of cataract: nuclear
cataracts are centrally located and have a brown-colored center; cortical
cataracts have irregular radiating spokes; and posterior subcapsular cataracts
appear irregular and rough and are located on the back surface of the lens. In
mature cataracts all of the lens protein is opaque; in immature cataracts, some
of the lens protein is transparent; and in hypermature cataracts the lens
protein becomes liquid.
Radiographic studies may be used to determine the presence of a metallic
foreign body if lens opacity follows ocular injury.
- Ophthalmoscopic examination
- Slit-lamp examination
- Neodymium-YAG laser
The progression of lens opacities varies considerably among patients, and
medical therapies are usually of short-term benefit only. For example, some
cataracts may be managed with a change in prescription, especially those
associated with refractive changes, and all cataracts may be treated temporarily
by dilation of the pupil, which allows light to go around the opacity (glaucoma
must be ruled out prior to use of mydriatics).
- Some studies have suggested that high-dose aspirin therapy given for
other causes (e.g., arthritis) is associated with a decreased incidence of
senile cataract; however, most of the evidence is speculative.
- Eye drops (e.g., phenylephrine [Neo-Synephrine, 2.5%], homatropine,
2%), to dilate the pupil to provide better vision in patients with nuclear
sclerotic or posterior subcapsular cataract
- Aldose reductase inhibitors, to prevent conversion of sugars to
polyols in galactosemic or diabetic patients, thereby preventing or delaying
- Prophylactic antibiotics for three weeks following cataract
- Steroid eye drops three to six weeks following cataract
Cataract surgery is usually elective except in the presence of uveitis or
glaucoma; surgery is recommended when the cataract interferes with the patient's
work, hobbies, or activities of daily living; if the cataracts threaten to
result in uveitis, iridocyclitis, or glaucoma; or if other ocular surgery is
necessary, making visualization imperative.
Intracapsular cataract extraction—extraction of the
entire lens, including the capsule of the lens. This can result in aphakic
vision, which is corrected with contact lenses or eyeglasses.
Extracapsular cataract extraction—extraction of the
anterior lens capsule, the nucleus, and the cortex, leaving the posterior
capsule intact. This can result in secondary opacification of the posterior
capsule, which is often treated by laser therapy in which a small opening is
made in the posterior capsule.
Intraocular lens implantation—insertion of a plastic
posterior chamber lens at the time of cataract extraction, which reduces the
problems associated with aphakia. (Anterior chamber lens replacement may damage
the corneal endothelium resulting in bullous keratopathy [edema of the corneal
stroma]; thus, this procedure is rarely performed.)
|Complementary and Alternative
Nutritional and herbal therapies help prevent and minimize the progression of
cataract formation. Correcting underlying nutritional deficiencies and
addressing contributing factors, such as diabetes, is essential to
- Increase dietary antioxidants which may protect against free radical
damage to the eye, especially dark leafy greens and orange and yellow
vegetables. Dark berries, particularly blueberries, are rich in flavonoids,
which may be protective to the lens.
- Vitamin C (500 to 1,000 mg bid to tid) is found at high concentrations
in the lens of the eye and has antioxidant activity.
- Glutathione is highly concentrated in the lens and protects against UV
light. Supplementing with glutathionine (200 mg bid) or its amino acid
precursors (L-cysteine 200 mg bid, L-glycine 100 mg bid, and L-glutamine 100 mg
bid) may be beneficial.
- Selenium (200 mcg/day) is a co-factor for glutathionine peroxidase
which helps keep glutathionine in its active state.
- Vitamin E (400 IU/day) protects against free radical
- Zinc (15 to 30 mg/day) deficiency may contribute to cataract
formation, especially with impaired glucose metabolism occuring with diabetes or
- Vitamin A (10,000 IU/day) and beta-carotene (50,000 IU daily) are
antioxidants that protect against light-induced damage to the
Herbs may be used as dried extracts (pills, capsules, or tablets), teas, or
tinctures (alcohol extraction, unless otherwise noted). Dose for teas is 1
heaping tsp. herb/cup water steeped for 10 minutes (roots need 20
- Dusty miller (Cineraria maritima) succus (preserved plant
juice) 1 to 3 drops bid to affected eye. May cause eye irritation.
- Bilberry (Vaccinium myrtillus) (200 mg bid) to increase
microcirculation and provide protective flavonoid support. Other flavonoids that
may be used in addition to bilberry to decrease inflammation are quercetin (200
to 500 mg bid to tid) and rutin (200 mg tid).
- Ginkgo biloba (160 mg
An experienced homeopath should assess individual constitutional types and
severity of disease to select the correct remedy and potency. A homeopathic
remedy may address causative factors and minimize the progression of cataract
Contrast hydrotherapy. Alternate hot and cold applications to the face or
back of neck to improve circulation to the head and facilitate the transport of
nutrients to the eye. Alternate three minutes hot with one minute cold and
repeat three times. This is one set. Do two to three sets per
Patients with cataracts can be monitored for progression of disease over a
long period of time before opting for cataract surgery. Patients who have
recently undergone cataract surgery should be monitored for rare but serious
complications such as intraocular hemorrhage, postoperative infection, corneal
decompensation, or problems with wound healing.
Patients who must take steroids for more than two years or who must take high
doses of steroids for short periods must be monitored for steroid-induced
Patients given cycloplegic mydriatics to dilate the pupils to delay cataract
surgery must be monitored for intraocular
A number of agents are purported to delay cataract formation but none are
known to reverse the progression of cataracts once begun. Prevention may be
assisted by the use of UV-blocking sunglasses.
Use of contact lenses to correct aphakic vision after intracapsular cataract
extraction is problematic (e.g., loss, infection, dislocation, corneal
decompensation) and rarely successful in patients over 60 years
- Spectacle lenses to correct aphakic vision are unable to correct side
vision, to which a number of patients are unable to adjust.
- Opacification of a retained posterior lens capsule is a common
sequela, but it can be treated successfully with laser therapy.
- Cataract surgery predisposes individuals to retinal detachment and
systoid macular edema.
Approximately 95% of patients who elect to have cataract surgery can expect
improved vision almost immediately. After-cataract is a common inflammatory
condition that most often results from changes in tissues left behind after
extracapsular cataract surgery or after trauma; inflammation results in
hemorrhagic, pigmentary, and fibrotic changes that may produce synechiae,
pupillary distortions, glaucoma, and retinal detachment.
Age-related cataracts are not likely to be seen in women in their
childbearing years. However, maternal infection, drug ingestion, or radiation
therapy during pregnancy may cause cataracts in the
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Copyright © 2000 Integrative Medicine
CommunicationsThis publication contains
information relating to general principles
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