Nearly half of the world’s blindness is caused by
age-related cataracts. In the United States alone, 5 million people have
diminished vision due to cataracts, including over half of those 80 years and
older.
Yet cataracts are among the most treatable vision problems.
Revolutionary advances in surgery and the development of sophisticated lens
replacements have not only restored vision to millions, but have actually
improved vision for many by correcting other lens-related defects.
The American Academy of Ophthalmology has designated August as Cataract Awareness Month, and
as a part of that effort the physicians of Hattiesburg Eye Clinic want to get
the word out about the effects of cataracts on vision and what can be done
about it.
“Cataracts are a part of the aging process,” says Dr. Stoney
Williamson. “Anyone 50 and over is going to have some form of cataracts that
get progressively worse. At what point they may need treatment will depend on
how much the cataracts have diminished their daily activity.”
The eye’s natural lens, a transparent structure between the iris
and the retina consists mainly of water and protein. Light waves entering the
eye pass through the lens and are focused on the retina, a layer of
photoreceptor nerve cells at the back of the eye. The retina converts the light
rays into electrical impulses that are then transmitted to the brain as sight
by way of the optic nerve.
As we age, though, some of the lens’s protein will begin to
clump and cause a cloudy area – a cataract – to develop in the lens. As the
cataract enlarges, the increased clouding distorts or light passing through the
lens. The person’s vision blurs (sometimes resulting in double vision or
multiple images), colors fade and night vision becomes poor. In time, the
person’s ability to see anything clearly fails altogether.
Surgery to remove the clouded lens has been a standard treatment
for decades. In the last twenty years, however, cataract surgery has taken a
quantum leap – advances in laser technology and the introduction of the intraocular
lens (IOL) have turned the procedure into an outpatient treatment that takes
only a few minutes to perform, with a shorter recuperative period and better
long-term outcomes.
“I don’t believe I can even remember how to perform cataract
surgery as we did when I first entered practice,” says Dr. Williamson, “that’s
how much has changed. We’ve seen a 45-minute procedure with an overnight
hospital stay and a long recovery period become a ten-minute procedure where the
patient goes home the same day and can resume anything but strenuous activity
almost immediately.”
The key to current state-of-the-art cataract treatment is
the IOL. According to Dr. David Richardson, there are three basic types of
these artificial lenses that permanently replace the clouded lens that is
removed during surgery. And all of them can correct vision problems associated
with the natural lens not related to cataracts.
“The standard IOL can correct far-sighted vision and to some
extent near-sighted, but not astigmatism,” says Dr. Richardson. “A toric lens
takes it one step further and can correct for astigmatism. The third type, the
multi-focal, can correct all of these categories, including intermediate distance
vision.”
