MONDAY, Feb. 11 (HealthDay News) -- That twinkle in your eye
could be an early sign of eye disease if it is seen using a new
imaging device developed by scientists at the University of
Michigan.
The device detects certain proteins that become fluorescent
during the metabolic stress that typically happens at the onset of
eye diseases, according to findings published in the February issue
of the
Archives of Ophthalmology. This flavoprotein
autofluorescence (FA) occurs when retinal cells begin to die.
"Autofluorescence occurs when retinal cells begin to die, often
the first event in diseases like glaucoma and diabetic
retinopathy," study co-author Howard Petty, a biophysicist and
expert in imaging with the university's Kellogg Eye Center, said in
a prepared statement. "Cell death can be observed microscopically,
but not as yet through any current imaging methods. We believe this
study is a big step forward, toward creating a diagnostic tool that
can characterize disease long before symptoms or visible signs
appear."
Many severe eye diseases do not show early symptoms before they
begin to diminish vision. Using this device to test a patient is
noninvasive and takes less than six minutes, according to the
study.
In the study, Petty and fellow researcher Victor M. Elner used
the instrument to measure the degree to which a subtle visual
condition affected six women. The women had been recently diagnosed
with pseudotumor cerebri (PTC), a condition that mimics a brain
tumor and often causes increased pressure on the optic nerve that
can lead to vision loss.
Because each woman's disease was in a very early stage, the
researchers could evaluate how accurately the instrument would
detect vision loss as compared to several standard tests used to
evaluate vision. In each case, their imaging instrument provided
results that were equal to and often superior to the standard
tests.
The researchers also found that FA data more accurately
described the degree of disease in each patient's eye as compared
to the standard vision tests. The patients with PTC had FA values
that averaged 60 percent greater in the eye that was more severely
affected, the study said. By contrast, an age-matched control group
had no significant difference in FA values between their healthy
eyes.
"Early treatment for eye disease is so important, and this study
suggests that FA activity is a very good indicator of eye disease,"
Elner, an ophthalmologist and a pathologist, said in a prepared
statement. "Cardiologists have long used blood pressure testing to
head off heart disease. We believe that FA testing will likewise be
a helpful diagnostic tool for eye doctors looking to prevent
blindness."
Elner and Petty have patented the device and are investigating
its use as a screening device in diabetes and major eye
diseases.
More information
The National Eye Institute has more about
eye diseases
and disorders.