NASA Device Could
Help Detect Cataracts
Researchers are studying the use of a NASA device that can be to
test whether a cataract is developing before a patient’s vision
begins to cloud over.
The noninvasive test can determine if the eyes are losing the
natural compound that keeps cataracts, a condition where the
eye's normally clear lens becomes permanently clouded, at bay.
Cataracts are currently the world’s leading cause of vision
loss, and surgery to replace the lens is the only fix.
Interestingly, the device also allows for easier testing of
whether certain medications might slow or prevent cataracts from
ever forming in the first place.
Research involving astronauts, who are at an increased risk of
the condition, and civilians could begin this year.
Knowing their eyes are vulnerable to cataracts could spur people
to alter their behavior to reduce their risk, such as avoiding
cigarette smoke, improving diet and wearing sunglasses.
Although the government has only a few prototypes of the device
and no commercial manufacturer yet lined up, doctors at
Baltimore's Johns Hopkins University have started experimental
use to determine what role the exam might play in the care of a
variety of eye patients.
"It's like an early alarm system," Dr. Manuel Datiles III of the
National Eye Institute, who led a study of 235 people that found
the laser light technique can work, told the Associated Press.
It all began when Rafat Ansari, a NASA senior scientist with the
agency’s John Glenn Research Center in Cleveland, developed a
low-powered laser light device to assist astronauts with
experiments growing crystals in space.
Ansari, an expert in physics, not medicine, began looking into
the novel use of the device after his father developed
Surprised at the lack of options for those with the condition,
Ansari read up on cataracts and learned that the lens primarily
consists of proteins and water. One type of protein, alpha-crystallin,
is critical to keeping the lens transparent. When other
proteins get damaged, either by aging, cigarette smoke or the
sun's UV radiation, the alpha-crystallins literally scoop them
up before they can stick together and clog the lens. Humans are
born with a certain amount of alpha-crystallin, but once the
supply is depleted cataracts can form.
Since his space laser measures proteins that make up crystals,
Ansari thought, perhaps it could also spot cataract-related
So he purchased calf eyes at a slaughterhouse, and enlisted his
then-teenage daughter, now a doctor, to dissect the lenses in
their kitchen. He placed them in the refrigerator, and tested
them after the cold clouded the lens’ over. Although he didn’t
know it at the time, biologists use the same technique to create
models of human cataracts.
When Ansari warmed up the lenses and beamed his device, he
discovered that the light scattering differed with the lens'
changing opacity. He then sought out eye specialists to see if
the technique might be applicable in measuring levels of alpha-crystallin.
While it took over ten years of testing, the result is a machine
that does just that. It works by aiming Ansari's special laser
at the lens for five seconds and then calculating light
Researchers at the National Eye Institute tested 235 people ages
7 to 86, and found that alpha-crystallin decreased consistently
both as lenses began to fog and as people with clear lenses
"What we are really looking at is the reserve of this
alpha-crystallin," Ansari told the Associated Press.
It can "repair any damage if there is a certain concentration.
If it depletes below that level then I think the game is over,”
Researchers with NASA and NIH are now planning separate studies
to see if special formulations of antioxidants, nutrients found
in many fruits and vegetables that fight certain age-related
tissue damage, can slow the loss of alpha-crystallin.
Ansari also plans to measure the impact of long-term space
travel on the vision of astronauts.
Already, Datiles has used the device diagnose early stage
cataracts in some patients whose doctors found no other reason
for their worsening vision.
At Hopkins, ophthalmologist Dr. Walter Stark is using the device
to determine if some patients complaining that their LASIK
surgery for nearsightedness is wearing off need may require more
vision-sharpening surgery, or if they might instead be forming a
The National Eye Institute study was published in last month's
Archives of Ophthalmology.