Early Predictor for Glaucoma Identified
Glaucoma is an eye
disease which involves damage to the optic nerve. It can lead to permanent
vision damage and lead to blindness if left untreated. Glaucoma often, but not
always, involves increase fluid pressure inside the eye, known as intraocular
pressure. A new study has found that certain changes in blood vessels in the
retina may be an early warning that an individual has an increased risk of
glaucoma.
Researchers from the Australian Blue Mountains Eye Study showed that
people with abnormally narrow retinal arteries at the beginning of their
10-year study were most likely to develop glaucoma by the end of the study.
The most common form of glaucoma is open-angle glaucoma (OAG), affecting nearly 3 million people in the USA and 60 million people globally. The loss of vision occurs when the glaucoma damages the optic nerve and signals are not passed from the retina to the brain.
Because there are no
symptoms, the disease often sneaks up on people unaware of its existence until
part of their vision is gone, making early detection extremely important.
The study, led by Paul
Mitchell, M.D., Ph.D. from the University of Sydney, tracked almost 2,500
participants. The results support the conclusion that abnormally narrow retinal
arteries were associated to four-fold increased risk of glaucoma.
Nobody had OAG at the
beginning of the 10-year study. Those diagnosed with the eye disease at the end
also tended to be older, had higher blood pressure or intraocular pressure at
the beginning, and were more likely female. The results were adjusted for other
factors such as family history of glaucoma, smoking, diabetes, etc.
"Our results
suggest that a computer-based imaging tool designed to detect narrowing of the
retinal artery caliber, or diameter, could effectively identify those who are
most at risk for open-angle glaucoma," said Dr. Mitchell. "Such a tool
would also need to account for blood pressure and other factors that can
contribute to blood vessel changes. Early detection would allow
ophthalmologists to treat patients before optic nerve damage occurs and would
give us the best chance of protecting their vision."
The researchers advocate
for regular eye exams to catch glaucoma, a symptomless disease, before it
occurs or at least at its outset in order to save the patient's vision. The is
particularly true for individuals over age 40.
This study has been
published in the journal of the American Academy of Ophthalmology