CONTACT: DAVE PEDERSEN
283 Medical Laboratories
Iowa City IA 52242
(319) 335-8032; fax (319) 335-8034
UI ophthalmologist focuses on eye diseases, education related to
IOWA CITY, Iowa -- A major concern among people with diabetes is loss
of vision, a long-term complication of the illness and the cause of blindness
for more than 8,000 to 12,000 Americans each year. A University of Iowa
College of Medicine professor is working to better educate both the public
and other health care professionals on diabetes-related vision loss, and
to study the effectiveness of one type of eye surgery on diabetes patients.
"The longer a person has diabetes, the greater chance that person
will have some diabetes-related damage to the retina that can result in
vision loss," says Dr. Karen Gehrs, UI assistant professor of ophthalmology
and a retina specialist at the UI Hospitals and Clinics. "Blindness
from diabetes is preventable in most cases, if problems are detected early.
Currently, however, almost half of patients with diabetes in the United
States are not undergoing the recommended screenings to detect eye disease
at a stage where it can be treated successfully."
Gehrs is the Iowa coordinator for Diabetes 2000, a nationwide project
started in 1989 by the American Academy of Ophthalmology. Aimed at patients,
physicians and other health care professionals, the project's goal is to
eliminate preventable blindness from diabetes through education and public
Gehrs is developing educational materials about diabetic retinopathy
(disorders of the retina that result in vision loss) for physicians who
care for diabetic patients at the UI and around the state. "With a
simple education strategy, we can increase physicians' awareness and emphasize
the need for eye examinations," she says.
Increasing pharmacists' awareness about diabetes-related eye disorders
is another avenue for prevention. Working with faculty at the UI College
of Pharmacy, Gehrs is developing lectures and presentations to be included
in the college's pharmaceutical care curriculum.
Gehrs is also helping UI pharmacy faculty prepare a diabetes education
program that pharmacists can implement at their practices. This includes
informational materials that pharmacists will share with their patients
and a continuing education program for pharmacists. "There is also
the possibility that pharmacists could check blood sugar or blood pressure
when a diabetes patient comes in to pick up a prescription, and keep a
database of the patients' visits," Gehrs says. "Then, when a
patient goes to see his or her doctor, there is an updated log detailing
their condition." Pharmacists' accessibility and regular contact with
diabetes patients who take medications would help make the program viable,
In areas of research, Gehrs is studying the effectiveness of vitreous
surgery for a type of swelling of the retina called diabetic macular edema
(DME). DME is a problem for many diabetes patients and is a result of poor
circulation in the macula, or central part of the retina, where vision
should be clearest.
"Think of the blood vessels in the macula as a network of capillaries.
DME occurs when capillaries become damaged and 'holes' develop in this
network," Gehrs says. The surrounding capillaries can compensate for
these damaged or missing blood vessels but eventually the area of missing
or damaged circulation becomes so large that the surrounding vessels just
can't keep up. The cells supplied by the damaged or missing capillaries
then become suppressed, the retina swells, and vision decreases.
Laser surgery does help many people with DME, Gehrs notes, but some
side effects do exist -- patients may see little spots or notice that things
"look dull" even though their visual acuity may be the same or
even improved. "Additionally, 25 to 35 percent of laser-treated patients
will still have persistent DME after the procedure," she says.
Gehrs is beginning a collaborative study with researchers at the Medical
College of Wisconsin that involves surgical removal of the vitreous humor,
the transparent, jelly-like material that fills the chamber of the eye
behind the lens. Previous studies have suggested that removing the vitreous
humor (a procedure known as a vitrectomy) may improve the amount of oxygen
that reaches the retina. Vitrectomies have been used for years to remove
hemorrhages from the eyes of diabetics with proliferative retinopathy,
or abnormal new blood vessels. Doing a vitrectomy to treat DME, however,
is a fairly new idea.
Working with 50 diabetes patients, researchers will look at patients
who have DME despite already having undergone one or two laser treatments.
"Basically, we will offer these patients a vitrectomy or another laser
treatment," Gehrs says. "A few pilot studies have been done with
vitrectomies for DME and some have reported high success rates -- sometimes
in the 90 percent range. But in those studies, no comparison was done between
laser and vitrectomy. Some patients in those studies may have gotten better
with laser treatment alone. In this study, we want to concentrate only
on those patients who don't respond to the initial one or two laser procedures."
Gehrs thinks there may be a subset of patients who do not respond to laser
treatment and who may be better off with vitrectomy before they've undergone
many laser sessions for macular edema.
Gehrs' interest in diabetes-related eye disorders stems partly from
the positive impact ophthalmologists can have in maintaining a diabetic
patient's vision. "Diabetic patients often have a myriad of health
concerns," she says. "If we can keep a patient's vision stable
and reduce the risk of blindness, we can make an enormous impact on their
quality of life and their ability to remain independent."