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Pigment Dispersing Syndrome Another
cause of glaucoma is considered to be the pigment dispersing syndrome
(PDS) or pigmentary glaucoma. In PDS, the concavity (curving inward) of
the mid-peripheral iris allows iridozonular contact, causing a shedding
of the pigmented iris. Released pigment is then carried to the
trabecular meshwork where it can reside benignly, not affecting the
IOP, or it can malignantly elevate the IOP, as in pigmentary glaucoma.
Flattening of the concave iris by mitotic therapy and laser iridotomy
appears the key to current and future management. Studies confirm that
PDS is inherited as an autosomal dominant trait, observed most
frequently in young, myopic (nearsighted) men (Campbell et al. 1995).
An autosomal dominant trait is one in which the inheritance of a
dominant gene on an autosome, not a sex chromosome, causes the
characteristic to be expressed.
Note: Primary
juvenile glaucoma is a rare form of glaucoma that typically affects
individuals from 3-20 years of age, and it, too, is an autosomal
dominant trait (Wiggs et al. 1995).
In some individuals, exercise causes pigment release and an increase
in IOP, contributing to the complexities of PDS management. A study
conducted at the Institute of Ophthalmology in Italy determined that
exercise-induced pigment release temporarily obstructs the aqueous
outflow channels, causing IOP increase in some patients with PDS.
Pre-exercise treatment with dapiprazole, an alpha-adrenergic blocking
agent, was useful in reducing IOP spikes and increasing outflow
facilities after intensive exercise (Mastropasqua et al. 1995;
Mastropasqua et al. 1996).
Scientists are one step closer to locating the gene responsible for
PDS. The New England Medical Center in 1997 stated that the telomeric
end of the long arm of chromosome 7 appears incriminated in PDS.
Locating a gene responsible for this condition is the first step toward
the isolation of the gene itself. Characterization of the responsible
gene will potentially lead to new methods of diagnosis and treatment.
PDS is one type of glaucoma, accounting for 12-15% of all cases of
blindness each year.
TREATMENT OPTIONS
Current Drug Therapy Betaxolol,
a beta-blocker presently used to reduce IOP, has calcium
channel-blocking functions. Experimental studies show that betaxolol is
an efficient neuroprotective agent against retinal ischemia in animals
when injected directly into the eye or intraperitoneally. Betaxolol
exerts its primary neuronal actions on retinal ganglion cells.
Unfortunately, betaxolol has an aggressive list of side effects.
Interviews with hospital pharmacists revealed two prescription drugs
being filled with more regularity than others for the treatment of
glaucoma. Timoptic eye drops, a beta-adrenergic blocking agent,
represents an older, but still popular, approach to treating glaucoma.
Xalatan, a prostaglandin analogue, generically known as latanoprost, is
a newer method of treatment. Its mechanism of efficacy deals with
replicating the activity of prostaglandins, hormone-like unsaturated
fatty acids that act in minuscule amounts on local target organs.
Latanoprost reduces IOP by increasing the outflow of aqueous humor.
Research conducted at the University of Nebraska Medical Center
involved 272 patients taking latanoprost for one year (Camras et al.
1996). Of those enrolled in the study, about 70 individuals withdrew
before the end of the study. Withdrawals were caused in 1% by
inadequate control of IOP; 5% because of increased iris pigmentation;
3% because of other ocular problems; and 17% because of unrelated
medical and nonmedical reasons. The final consensus was that
latanoprost safely and effectively reduces IOP for one year, evidencing
its usefulness in POAG. However, latanoprost usage can cause a
darkening of the pigment in the iris, which might aesthetically
disappoint a unilateral glaucoma patient.
Supplements That May Lessen Neurotoxicity and Glaucoma Progression Experimental
studies have identified a variety of naturopathic substances that may
prove useful in preventing the death of retinal neurons, particularly
ganglion cells, induced by ischemia. It may be possible to protect
cells against glutamate toxicity by taking methylcobalamin supplements,
the biologically active form of B12 (Akaike et al. 1993; Kikuchi et al.
1997). Methylcobalamin is immediately active upon absorption, although
cyanocobalamin must be converted to either methylcobalamin or
adenosylcobalamin by the body, removing the cyanide molecule and adding
either a methyl or adenosyl group.
Note: The amount of cyanide produced in the conversion process is extremely small.
Acetyl-L-carnitine is said to possess efficacy by attenuating
age-related neural deficits. Acetyl-L carnitine has produced stunning
results in protecting neurons in a wide range of disease processes.
The antioxidant activities of lacrimal fluid and blood plasma were
studied in glaucoma, as compared to normal eyes (Makashova et al.
1999). The findings indicate that the progress of glaucoma is
paralleled by a gradual decrease in the lacrimal fluid antioxidant
levels. A broad-spectrum antioxidant is a recommendation frequently
made by various national and international researchers with regard to
glaucoma treatment. The antioxidant complex should provide 200-400 IU
of vitamin E daily.
Alpha lipoic acid (ALA), both water- and fat-soluble, is a
vitamin-like antioxidant, sometimes referred to as the "universal
antioxidant." Dr. Lester Packer, a scientist who heads the Membrane
Bioenergetics Group at the University of California, regards lipoic
acid as a "free agent," meaning that it can substitute for the other
antioxidants when they are in short supply. Primary evidence indicates
that 150 mg of alpha lipoic acid, taken daily for 1 month, improves
visual function and ocular hypertension in glaucoma patients (Filina et
al. 1995).
Thiamine (vitamin B1) has been used to improve visual acuity (van
Noort et al. 1987). This may be of particular advantage to glaucoma
patients, for thiamine-deficient states are frequently associated with
glaucoma (Asregadoo 1979).
Can Diet Make a Difference? The
watchful selection of foodstuffs appears to be another modality that
impacts the control level of glaucoma. The value of vitamin C has been
documented with regard to both lowering IOP and maintaining the
reliability of ocular collagen (Pfister 1980; Pasquali et al. 1997;
Head 2001). For this reason, glaucoma patients should acquaint
themselves with foods rich in this essential vitamin and use them
freely in meal planning.
Fresh fruits and vegetables are reliable sources of vitamin C.
Select from kiwi, bell peppers, broccoli, cabbage, citrus fruits,
Brussels sprouts, kale, parsley, strawberries, tomatoes, and cantaloupe
to contribute to an adequate vitamin C intake. Remember to emphasize
dark-colored berries (raspberries, blackberries, blueberries), grapes,
raisins, and plums, which are sources of anthocyanoside antioxidants
having a special affinity for the eye.
Try to plan a diet around whole, unprocessed foods, including whole grains, legumes, nuts, and seeds.
The omega-3 fatty acids have shown benefit in lowering IOP (Kulkarni
et al. 1989). One tbsp of flaxseed oil (a source of alpha-linolenic
acid) daily provides a good supply of omega-3 fatty acids. Because
flaxseed oil is highly polyunsaturated, it should not be heated.
Evidence is mounting pertaining to excitatory neurotoxins
encountered in our food supply. The most frequently encountered food
excitotoxin is glutamate, which is commercially added to many foods
despite evidence that it can freely penetrate certain brain regions and
rapidly destroy neurons by hyperactivating glutamate receptors (Olney
1994). Avoidance of glutamate may be of particular advantage to
individuals with glaucoma.
The herb oregano, from the mint family, may have a worthwhile place
in the diet of a glaucoma patient. James A. Duke, Ph.D. (1997) suggests
that of the 60 mints he investigated, all high in antioxidant value,
oregano had the highest concentration of antioxidants. He suggests
using 1-2 tsp of dried oregano per cup of boiling water. The
therapeutic strength of this drink can be amplified with the addition
of peppermint and rosemary.
Identify and eliminate the consumption of allergenic substances in
ingested food materials. Allergies are individualized and impossible to
distinguish universally, but milk, onion, eggs, and chocolate are among
the most common in patients.
Drink at least 48 oz of clean water daily. This amount should be
metered throughout the day, with at least 1-hour intervals, consuming
only a few ounces at one time. Individuals who enjoy juice in their
diets or support the healing benefits associated with juice may wish to
combine bilberry, cranberry, and huckleberry, all of which are high in
anthocyanosides. Avoid stimulating beverages, such as coffee and tea,
which cause vasoconstriction and elevated blood pressure.
Topical Eye Drops Research
shows that orally taken antioxidants will effectively raise blood
plasma levels of the nutrients, but the intake does not always
correlate directly in eye tissues. In one study, oral antioxidant
therapy normalized blood antioxidant levels in advanced glaucoma
patients but did not help lacrimal antioxidant activity. Although
further research needs to be conducted, this may indicate that
topically applied antioxidant eye drops may be the preferred treatment
in glaucoma patients (Makashova et al. 1999).
Lifestyle Changes Glaucoma
is considered to be a stress disease. Avoid emotional upsets and
upheavals, for external pressure increases internal ocular pressure
(Kaluza et al. 1996; Flammer et al. 1999). Try to develop a composed,
peaceful lifestyle. Climates with great temperature variances are
thought to be detrimental. More stable climates and temperatures appear
to be better tolerated by the glaucoma patient. Don't smoke, for
tobacco constricts blood vessels, reducing the blood supply to the eye.
Avoid prolonged eye stresses such as long movies, excessive TV viewing,
or excessive reading.
Discuss with your ophthalmologist your physical and sexual activity.
Normally, after treatment, regular exercise and activities are resumed.
Restraint should be observed to avoid fatigue. Sexual relations are
usually permitted, when eye pressure is under control.
SUMMARY
Current glaucoma research appears to focus on providing
neuroprotection to retinal ganglion cells (Osborne et al. 1999a;
1999b). This approach may benefit those displaying normal tension but
still experiencing progressive visual-field loss. Recommendations to
reduce IOP are also included. Glaucoma represents a serious eye
condition, requiring monitored supervision by a qualified
ophthalmologist. Best results might be obtained by working with a
complementary physician who employs the best of orthodox and
alternative wisdom.
Some of the following suggestions replicate the same mechanism and should be structured to individual needs:
- Vitamin B12, methylcobalamin, is the choice of many wishing to
delay the death of neurons observed in the aging process. Sublingual
methylcobalamin supplementation is considered therapeutic for central
and peripheral neurological damage, at dosages of 5 mg dispensed
throughout the day so that the total intake amounts to 40 mg a day. Do
not eat the tablet as one would candy. Let the B12 dissolve slowly
under the tongue. This form of vitamin B12 is an alternative to weekly
B12 shots and may be quite useful in the prevention of neurotoxicity.
- Aminoguanidine (300 mg daily) has shown neuroprotective
benefits. Aminoguanidine reduces nitric oxide, protecting against
oxygen deprivation and decreasing the death of the retinal ganglion
cells. Limited clinical experience involving aminoguanidine suggests it
should not be used in doses greater than 300 mg a day.
- Alpha-lipoic acid has attained favorable attention in the
treatment of glaucoma. It appears to improve ocular hypertension and
visual function. Current glaucoma research considers a daily dose of
150 mg adequate for glaucoma treatment.
Note: Much
larger dosages are used in diabetes and AIDS (300-600 mg daily) without
significant side effects. (This information is included to illustrate
the safety parameters of alpha lipoic acid.) Possible side effects
include skin rash and hypoglycemia. Lipoic acid can worsen a B1
deficiency. Chronic usage of lipoic acid can interfere with biotin
utilization, so make sure you are taking plenty of biotin and vitamin
B1 when taking over 100 mg a day of alpha lipoic acid.
- Topically applied eye drops may be a more effective delivery system
for antioxidant protection. Brite Eyes II contains nutrients that
protect against free radicals. The formula also contains the
antiglycating agent N-acetyl-L-carnosine, which helps prevent the
formation of nonfunctioning protein crosslinks. A daily dose of 1-2
drops in each eye is suggested for general eye health.
- The Vitamin Depot Online.comMix, 9 tablets or 14 capsules daily, or 1
tbsp. of powder daily provides a storehouse of nutrients, including
magnesium, zinc, chromium, selenium, vitamin A, thiamine, vitamin C,
bioflavonoids, grape-seed-skin extract, vitamin E, and bilberry, which
could benefit ocular health. Some individuals may wish to emphasize
additional amounts of the most beneficial of these herbs and nutrients,
regarding glaucoma management.
- Use vitamin C crystals or a powdered form of vitamin C,
buffered with magnesium. (This type is added to a liquid and is
considered highly absorbable.) The buffered form of vitamin C is easier
on the stomach when large amounts of ascorbate are ingested. The
magnesium will tend to act as a calcium channel-blocker and temper a
sympathetic nervous response. The vitamin C may assist in lowering IOP
and establishing healthy collagen. Some individuals will realize
benefit from as little as 2 grams of vitamin C daily; others will need
as much as 35 grams daily. Some practitioners use 500 mg of vitamin C
per kilogram (2.2 lbs) of body weight, a dose that must be reached
gradually. Vitamin C should be spaced throughout the day, allowing a
continuous supply of ascorbate.
- Grape-seed-skin extract, rich in proanthocyanidins,
increases the effectiveness of vitamin C. Together they support healthy
collagen and defend against free radicals. A therapeutic dose of
proanthocyanidins is considered to be 150-300 mg daily. Usually this
dose can be reduced after a month's saturation.
- Select bilberry by evaluating its anthocyanosides content.
(This is calculated by the percentage of anthocyanidin present,
typically 25%.) The dosage for bilberry, the "eye herb," is 100 mg, 2
times daily (or as directed by your health-care professional).
- Acetyl-L-carnitine is an important adjuvant in
neuropharmacology. A dosage of 3000 mg daily may be used. With most
supplements, including acetyl-L-carnitine, gradual introduction of the
supplement is advisable, allowing the body to adjust to the actions of
the substance.
- Individuals with healthy liver function may use
25,000-50,000 IU daily of vitamin A. (Some research indicates the
emulsified form of vitamin A is less stressful on the liver.) Vitamin A
from all supplemental sources should be calculated into the daily
total, being watchful of the cumulative amounts. Although toxicity is
not usually associated with low doses, people should acquaint
themselves with the symptoms of vitamin A toxicity (see Appendix A).
Pregnant women should use vitamin A only after careful consultation
with their physician. The benefits of vitamin A include decreased dry,
itchy, inflamed eyeballs and an increase in visual purple, a substance
needed for night vision.
- Select Coleus forskohlii standardized to contain 18%
forskolin. Use 50 mg (9 mg of forskolin 2-3 times per day) to assist in
lowering IOP.
Do not use C. forskohlii if prostate cancer is apparent. During C.
forskohlii usage, monitor blood pressure, being alert for hypotension.
- Hydergine's mechanism of efficacy appears similar to C. forskohlii.
Hydergine reduces hypoxia and free-radical damage. A dosage of 3-20 mg
daily is considered appropriate.
- Attempts to reduce stress are valuable to the glaucoma
patient. External stress begets internal stress, both of which equate
to physical disruption. Unpleasant interactions with others,
temperature extremes, and fatigue are not desirable for anyone,
especially individuals with glaucoma.
The preceding pages have delineated many pharmaceutical drugs that
have been efficacious in glaucoma control. Nutritional pharmacology
offers choices, as well. It appears important to have a relationship
with a physician who employs the best from all disciplines. Side
effects and quality of life should impact the selection of an ongoing
protocol. When contemplating the number of therapeutic agents available
to a glaucoma patient, obviously the individual has many options.
FOR MORE INFORMATION
Contact the Glaucoma Research Foundation, (800) 826-6693.
PRODUCT AVAILABILITY
Methylcobalamin, Vitamin Depot Online.comMix, ascorbic acid (vitamin C) powder, grape-seed-skin extract, bilberry, forskolin, liquid emulsified vitamin A, acetyl-L-carnitine, and alpha- lipoic acid
may be obtained by calling (800) 544-4440 or ordering online.
Aminoguanidine and Hydergine can be purchased offshore. Contact the
Vitamin Depot Online.comFoundation at (800) 226-2370 for further information. |