the eye either by causing the eye to
produce less fluid or by helping the eye
to drain fluid more effectively. Laser
surgery and/or intraocular surgery can
be done as an alternative to medication
or when medication fails to control the
glaucoma.
Conclusion
Glaucoma is a lifelong illness, but
proper treatment can prevent vision
loss. Although there is no way to
prevent glaucoma, there are many
successful treatments available to
prevent the potential blindness caused
by glaucoma. Because the gradual
vision loss of glaucoma may not be
noticed until it is too late, regular eye
examinations including tonometry,
dilated examination of the optic nerves,
and screening tests of the visual field
are essential for all persons age 40
and older, especially African-Americans
and people with a family history of
glaucoma. DMJ
References
1. Broman AT, Quigley HA, West SK,
et al. Estimating the rate of progressive
visual field damage in those with openangle
glaucoma, from cross sectional
data. Invest Ophthalmol Vis Sci.
2008;49(1):66-67.
2. Munoz B, West SK, Rubin GS,
et al. Causes of blindness and
visual impairment in a population of
older Americans: The Salisbury Eye
Evaluation Study. Arch Ophthalmol.
2000;118(6):819-825.
3. American Academy of
Ophthalmology Preferred Practice
Patterns Committee. Preferred Practice
Pattern® Guidelines. Comprehensive
Adult Medical Eye Evaluation. San
Francisco, CA: American Academy
of Ophthalmology; 2010. Available at
www.aao.org/ppp.
FOR MORE INFORMATION
ABOUT GLAUCOMA
April 2019 Dallas Medical Journal 9
Introduction
Glaucoma is the leading cause of
blindness among African Americans.
Primary open angle glaucoma
(POAG) is the most common form
of this disease. The cause of POAG
is unclear and treatment is the only
way to prevent vision loss. Multiple
studies have shown that the disease
disproportionately affects African
Americans, especially those with
a positive family history. African
Americans present with glaucoma at
an earlier age and with more severe
and rapidly progressing symptoms.1
Some studies estimate that African
Americans are up to 15 times more
likely to become visually impaired from
POAG than European Americans.2
POAG affects approximately 3 million
Americans older than forty. It is alarming
that half of these people do not know
they have glaucoma.
Vision loss from glaucoma occurs
when the optic nerve is damaged by
increased intraocular pressure (IOP).
Optic nerve damage causes peripheral
visual field loss that occurs slowly
and may extend centrally. It occurs so
slowly that visual field constriction often
is not readily noticed. As the disease
progresses, the field of vision gradually
narrows and blindness can result.
Glaucoma has no early symptoms and
often is referred to as the “silent thief of
sight.”
The Primary Open Angle African
American Glaucoma Genetics
(POAAGG) study is a five-year study
that was funded by the National
Eye Institute in 2014. To date
this study has enrolled more than
10,000 African-American patients.
Researchers currently are conducting
a genome-wide association study and
whole-exome sequencing to identify
the genes involved in glaucoma in
African-Americans. In the future,
this information will shed light on the
increased burden of disease and pave
the path to more targeted and effective
treatments.
HOUSE CALL
American Academy of
Ophthalmology: www.aao.org
National Eye Institute:
www.nei.nih.gov
Glaucoma Research Foundation:
www.glaucoma.org
The Foundation for Fighting
Blindness: www.blindness.org
Early Detection and Treatment
Since glaucoma has no early
symptoms, early detection and
treatment are critical in preventing
permanent, irreversible vision loss. Early
diagnosis depends on 1) identification
of risk factors; 2) evaluation of the
IOP; 3) examination of the optic disc,
retinal nerve fiber layer, and visual
field. In 2015, the American Academy
of Ophthalmology established formal
guidelines for the frequency of ocular
examinations.3 Their recommendations
are summarized as follows:
Adults without risk factors
Adults with no signs or risk factors for
eye disease should receive a baseline
comprehensive eye evaluation at age
40. Individuals without risk factors
age 40–54, should be examined by
an ophthalmologist every 2–4 years.
Individuals without risk factors age
55–64, should be examined by an
ophthalmologist every 1–3 years.
Individuals without risk factors who
are 65 years of age or older should
have an examination performed by an
ophthalmologist every 1–2 years as
the incidence of unrecognized ocular
disease increases with age.
Adults with risk factors
The frequency of ocular examination
in the presence of acute or chronic
disease will vary widely with intervals
ranging from hours to several months,
depending on the risks involved,
response to treatment, and potential for
the disease to progress. Any individual
at higher risk for developing disease,
based on ocular and medical history,
family history, age, or race should have
periodic examinations determined
by the particular risks, even if no
symptoms are present.
The frequency of ocular examinations
should depend on the individual’s
age, race, past ocular history, medical
history, family history of eye disease,
and the types of ocular symptoms/
findings encountered. If significant
ocular disease is detected, the
frequency of examination will depend
on the severity of the condition, the
response to therapy or surgery, and the
potential for detecting progression of
the abnormality.
Treatment of POAG usually begins
with prescription eye drops. These
medications lower the pressure inside
Sylvia Hargrave MD, FACS
Chief of Ophthalmology,
Methodist Dallas Medical Center
Director, Hargrave Eye Center
MINORITY HEALTHCARE SPECIAL FEATURE