Volume 3, Number 2
Fall, 1994
Common Misconceptions
about Glaucoma
by George L. Spaeth, MD
One
of the reasons so many patients with glaucoma get worse is that
they have serious misunderstandings and misconceptions about it.
Here are some of the more common ones.
Misconception #1:
People with glaucoma lose peripheral
vision.
It is a misconception that patients with glaucoma
lose peripheral vision. "Peripheral vision" for most people means
vision off to the side. That is, when a person is looking straight
ahead, peripheral vision means vision way off to the right side
and way off to the left side. But that kind of "side" vision is,
in fact, the last part of the
vision to be lost in people with glaucoma.
In most people, the initial damage to vision is
a mild generalized loss of sensitivity for contrast. The first
area of vision that is lost is on the nasal side of the visual
field; that is, for example, for the right eye, the earliest visual
loss would be just a little bit to the left-hand side of straight-ahead
vision. Since this area of vision is also served by the left eye,
the loss is not usually noted until most of the field is gone
in one eye or a similar area is damaged in both eyes.
Misconception #2: Glaucoma
is a well-defined condition.
"Glaucoma" encompasses such a wide variety of different
conditions that the word itself is almost meaningless. For example,
some patients with glaucoma can become totally blind within a
period of a half an hour. Others can be damaged by the glaucomatous
process so slowly that even after 20 years, there is still no
awareness of any decrease in visual function.
Some types of glaucoma, such as the ordinary "primary
open-angle glaucoma" almost always involve both eyes, whereas
other types, such as Chandler's syndrome, never involve both eyes.
Some types of glaucoma are so strongly hereditary
that 50% of the members of a family are likely to be affected,
whereas others have absolutely no familial tendencies at all.
To tell a person that he has "glaucoma" doesn't
really tell the person anything meaningful. Rather, the physician
should try to explain as carefully as possible what the patient
should expect: "You have a condition that has already caused a
major amount of damage; if nothing is done, it is likely to get
worse over the next three or four years," or: "With your type
of glaucoma you probably won't have any discomfort or have any
other clues that it's getting worse until the damage is marked.
So, you need a glaucoma specialist to monitor your condition."
In short,
it is not the glaucoma that is treated, it is the person
who needs to be treated, because it is the disease's effect on the
person that is the only important consideration.
Misconception #3:
People who have glaucoma have to use
their drops forever.
It is a misconception that once individuals "start
on drops" they must use them for the rest of their lives. However,
behind that misconception is a truth that frequently does apply:
specifically, that the tendency always to get worse is present
in many types of glaucomas and, therefore, vigilance may be necessary
for the person's entire life.
In some people, the need for medications to control
the intraocular pressure may spontaneously disappear. If drops or
other medications need to be continued, it is not because the person
is taking the drops that the drops need to be continued. Rather,
it is because the underlying problem with the glaucoma continues
to exist and some means to manage it continues to be necessary.
Misconception #4:
Surgery is appropriate only in desperate
cases.
The idea that one starts with weaker drops, progresses
to stronger medicine, and only as a last resort becomes a candidate
for surgery is another misconception about glaucoma.
This misconception is related to the variety of
ways in which glaucoma presents itself. Some types of glaucoma
are best treated right from the start with surgery. For example,
the commonest type of glaucoma that occurs in infants usually
responds well to surgery but never responds adequately to medicines.
On the other hand, with certain types of glaucoma,
it is best to avoid surgery, because the risk associated with the
surgery is far greater than the potential damage that would occur
if the surgery weren't done.
Misconception #5:
We can tell whether or not glaucoma
is being controlled by monitoring the level of the intraocular
pressure.
It is a misconception to think that control of
glaucoma is measured in terms of the intraocular pressure. It
is true that glaucoma is damage to the tissues of the eye that
is at least partially caused
by pressure higher than the eye can tolerate.
Nevertheless, people can go blind even though their
intraocular pressure is fairly constantly as low as 12 mm Hg,
well below the so-called "normal" level of pressure. Others can
maintain pressures of 25 mm Hg -- much higher than "normal" --
for many, many years and yet never develop any damage at all.
Control of glaucoma can be defined only in terms
of whether or not there is increasing damage. Where the damage is
increasing, the glaucoma must be defined as "uncontrolled," regardless
of the pressure. Where it is not increasing, the glaucoma must be
defined as "controlled," regardless of the pressure.
Misconception #6:
What the glaucoma patient does doesn't really
make very much difference.
A particularly tragic misconception about glaucoma
is that what the patient does doesn't really make very much difference.
In fact, how a person manages his or her life is probably the
single most important factor determining whether that person maintains
his or her sight.
Choosing a competent doctor is an important part
of that management, as is helping the doctor do his or her job
competently. The patient is really the senior partner and the
physician the junior partner. The patient has the responsibility
of being alert to how he or she is doing, both from the point
of view of general health, quality of life, and visual function,
and of passing that information on to the physician. The physician
has the responsibility of listening, understanding, and drawing
appropriate conclusions.
Patients are responsible for educating themselves,
using the physician to help them in that process. The more a patient
knows, the better it is.
An important example is patient awareness that
general health significantly affects the course of glaucoma damage.
For example, to help maintain vision, the overweight person should
lose weight and the sedentary person should exercise.
Perhaps the most important
thing to understand about glaucoma is that each case is different
and that the greatest success in terms of maintenance of quality
of life as related to vision occurs when the individual patient
really takes responsibility for his or her own well-being and
then works with a knowledgeable, competent physicians, who truly
listens and truly cares for the person as an individual.
The Glaucoma Service Staff at Work
Dr. Marlene R. Moster, long-term member of the Glaucoma Service
staff, administers drops to a patient. Like most of the other
staff physicians, Dr. Moster is also very much involved in the
Foundation's research programs, in particular projects related
to her area of expertise, ocular pharmacology--drugs used in the
eye.
(Photograph by Roger
Barone)
Glaucoma - A World Problem
Glaucoma is not just a national
problem, it is a world problem. As such, it requires an international
response. Knowing this, it is gratifying for us to host glaucoma
surgeons and researchers from literally all corners of the globe.
Sometimes it is assumed that our visitors are the benefactors.
And, indeed, they are eager to observe our clinical work and research
activities. Nevertheless, we often feel that we are the
ones who end up learning the most!
 Pictured
with stereo fundus photographic equipment are short-term observers
Dr. David Moran (right), an experienced glaucoma surgeon from
Port MacQuarie, Australia, and Doris Ruskovic (left), a medical
student from Munich, Germany, in her final year of study. As Medical
Director of the Fred Hollows Foundation, a major player in fostering
eye care in third-world nations, during his 2 months with us,
Dr. Moran reports he had a most pleasant and profitable visit,
observing surgery and talking to Fellows and Residents. Ms. Rushovic
explained that German medical students in their final year of
medical school are expected, among other things, to serve for
three or four months in a specialty of choice.
 Da-Wen
Lu, MD, PhD (left) and Kun Jin Yang, MD (right) are the Foundation's
most recent full-time research fellows. Dr. Lu, who is from Taiwan,
is Associate Professor of the Department of Ophthalmology of the
National Defense Medical Center. The recipient of numerous fellowship
and grants, Dr. Lu already has over 25 publications to his name.
Dr. Yang, who is from Korea, is Assistant Professor in the Department
of Ophthalmology at Chonnam National University Medical School.
Among his projects is a study of adverse reactions to important
drugs used to control intraocular pressure, the carbonic anhydrase
inhibitors.
Foundation President George Spaeth, MD (left),
chats with former Research Fellow, Vital Costa, MD (right), and
recently named Research Coordinator, Silvana Araujo, MD (middle).
Dr. Costa, in the country to present a poster at the American Academy
of Ophthalmology meeting in San Francisco in early November, told
us about his latest activities in his native Brazil. He is currently
Chief of Glaucoma Service at the University of Campinas ("among
the three best university hospitals in Brazil") and attending surgeon
at the University of Sao Paulo ("the best"), where he sees 80 to
100 patients a week. One of his major tasks is educating Brazilians
about glaucoma so that they will understand the importance of acting
on their doctor's instructions to prevent further loss of sight.
(Photographs by Jamie Nicholl)
Recent Visitor Writes
Dr. Fransisco Campiolo, who is from Brazil, after having spent
several weeks with us, wrote Dr. Spaeth the following letter:
"I still have in my mind
the lovely days I spent in Philadelphia. I would like to thank
you again for this great opportunity that you gave me to learn
about this fascinating and interesting disease. I now believe
I'm taking care of my glaucoma patients better than ever. I feel
safer in choosing the correct procedure to treat each individual
patient.
I would like to wish you and
all the Glaucoma Service staff a Merry Christmas and Happy New
Year. Thank you for receiving me like a member of your Department---not
a foreigner."
What Glaucoma Patients Know and Don't Know
by Ken Parker, PhD
The better glaucoma patients
understand their disease, the more likely it will be successfully
treated. Few studies have sought to discover exactly what glaucoma
patients know and do not know about glaucoma. Foundation researchers
Drs. Vital Costa and Cordelia Uddoh are presently completing a
study of 183 consecutive patients with the most prevalent type
of glaucoma, primary open-angle glaucoma, being seen on the Glaucoma
Service of Wills Eye Hospital or in the private practice of Drs.
Spaeth, Katz, and Terebuh.
Here are some of the questions
asked of the 186 patients and the answers given:
Question: Do you
believe your eyes are healthy?
Result: Sixty-one
said they thought their eyes were healthy; 122 did not.
Question: Do you
have an eye disease? What disease do you have?
Result: 128 patients
said they had an eye disease, while 52 did not think so. Glaucoma
alone was cited by 77.5% of the patients; 15% indicated glaucoma
plus some other eye disease; four said they had an eye disease
but were unsure whether it was glaucoma; another four who clearly
had glaucoma mentioned an eye disease other than glaucoma.
Question: What
was your intraocular pressure (the pressure the fluid inside the
eye exerts on the tissues of the eye) at your last visit? What
is an average intraocular pressure?
Result: Sixty-two either
did not know or did not remember their latest intraocular pressure.
Sixty-seven did not know what the average introcular pressure
is. Forty thought it was in the range of 16 to 20 mm Hg (millimeters
of mercury); 36, in the range of 11 to 15 mm Hg; 16, in the range
of 6 to 10; and four, in the range of 21 to 25. Eight said it
was individualized. [While 16 to 20 is a reasonable answer, in
actuality, the best response is that it is individualized.]
Question: Is your
visual field normal? Why is the visual field measured?
Result: Seventy-six
thought their visual field was normal. [Whether in fact they were
is still being determined, but it seems highly unlikely that 76
patients with confirmed glaucoma actually did have normal visual
fields.] Eighty-one patients did not know why the visual field
is measured. [The visual field is measured to determine the extent
of damage to the optic nerve associated with glaucoma.]
Clearly, much work needs to
be done to educate glaucoma patients about their disease. This
is one of the most important functions of the Glaucoma Service
Foundation to Prevent Blindness and the Searchlight
newsletter.
Foundation Receives $100,000 Bequest
The Foundation was informed
in November that we would be soon receiving a $100,000 bequest
from the Estate of Alice. M. Van Dyke. Ms. Van Dyke was apparently
not a patient on the Glaucoma Service; we are still seeking background
information about her.
Join Us!
You can help support the research
and education activities of the Glaucoma Service Foundation to
Prevent Blindness. To make a donation to our Annual Fund click
here.
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