At Carolina
Ophthalmology, we check intraocular
pressure (IOP) at all regular eye exams. Checking IOP is a very important
way to screen for Glaucoma.
Glaucoma is
a chronic disease that affects both eyes, and is the second commonest form of
blindness, affecting about 1.6 million people in the United States. Known as
the “silent thief of sight,” glaucoma can cause slow, painless, progressive
loss of vision. Untreated, high IOP damages the optic nerve and causes vision
loss. Many patients experiencing slow loss of peripheral vision don’t notice
that it’s happening, and once that damage has occurred it cannot be undone. To
read more about Glaucoma, click here.
Due to the
lack of noticeable symptoms, early detection through routine screenings is
important. This preventative measure allows for early diagnosis and treatment
before irreversible damage occurs.
Checking IOP
is one way to screen for Glaucoma, and is done along with a dilated exam so the
doctor can look at the optic nerve, photographs of the optic nerve, and a
visual field test to determine if vision loss has occurred.
There are
many ways to check a patient’s IOP, including the dreaded puff-of-air test. We
use a more accurate, less terrible test called applanation tonometry (blue-light test). This test involves a
Goldmann Tonometer attached to a slit lamp which measures the force required to
flatten (applanate) a small segment of the central cornea.
First, the
technician will put a drop into your eye that is a numbing agent mixed with
fluorescein. The eye is completely
numbed and the patient does not feel the prism touch his or her eye. The
fluorescein in the drop causes the eye to glow yellow under the blue light of
the tonometer. Next, the technician looks through the instrument and adjusts
the pressure of the applanator until it matches the pressure inside the eye.
This number is the patient’s IOP.
Most normal
eyes have IOP between 10 and 20. However, some eyes cannot tolerate even these
normal pressures, and others can have higher pressures than these without
damage. Patients with high IOP, or with a family history of Glaucoma, should be
closely monitored. Due to the damaging effects of Glaucoma, early detection and
effective control of IOP through prescription drops is vital to preserving
vision.
Call us
today to schedule an eye exam and have your IOP checked at 919.967.4836.
