This article originally appeared in Pathways, a magazine
published for physicians and the community by UMass Memorial Medical
According to the World Health Organization, cataract is the leading cause of
blindness in the world. In this country, however, cataract is often considered
"conquered" since treatment to restore vision loss from the condition is so
widely available. But cataract is widespread, nonetheless, appearing with
advancing age. In fact, today the condition affects more than 20 million
Americans age 40 and older, or about one in every six people in this age range.
By age 60, more than half of all Americans have cataract.
When cataract clouds the eye's naturally clear crystalline lens, surgery to
remove the affected lens is the only effective treatment; neither diet nor
medications have yet been shown to reverse or prevent cataract formation. The
lens is usually replaced with an artificial intraocular lens (IOL) implant.
Cataract removal is now one of the most commonly performed surgical procedures,
with nearly 1.5 million such procedures performed each year. It is also one of
the most successful, with an overall success rate of 98 percent.
Cataract surgery's success and popularity are due in large measure to a
relatively recent advance known as the no-stitch procedure. Just a generation
ago, cataract surgery was considered risky, required a lengthy hospital stay and
recovery period, and was often postponed for as long as possible - until vision
impairment was severe. Today, however, cataract surgery is performed on an
outpatient basis, takes only a few minutes, and patients are back to their
regular activities the next day. Moreover, many patients can see even better
than they could before they developed cataracts. George Asdourian, MD, medical
director of ophthalmology at UMass Memorial, explained:
"When I was a resident, we performed conventional intracapsular and
extracapsular cataract surgery that required a larger (10 - 12 mm) incision and
multiple stitches for closing," he said. "The patient was hospitalized for a
week without being ambulated. Healing was slower and visual recovery generally
took two to three months." To replace the focusing power of the removed natural
lens, the patient was required to wear contact lenses or thick eyeglasses.
Moreover, the stitches could cause distortion of the normal curvature of the
cornea, leading to astigmatism and blurred vision.
"In the last decade or so, new technology has made cataract surgery faster,
easier and safer," Dr. Asdourian continued, referring to phacoemulsification and
advances in IOLs. This "no-stitch" approach to cataract surgery is now the
preferred form of cataract removal, and recent advances and refinements in
machine and microsurgical instruments have made it even more effective.
The technique of phacoemulsification requires a very small incision,
generally 3 mm in width. A tiny ultrasonic probe is introduced into the eye
through this incision, and localized high-frequency sound waves break the
cataract into microscopic particles. The particles are gently suctioned away
through the probe, leaving the thin capsule.
A folded IOL is then inserted through the micro-incision, unfolded and placed
into permanent position. Because it is so small, the incision is self-sealing
and requires no sutures, remaining closed by the natural outward pressure within
the eye. If a lens implant is used that cannot be folded, the incision usually
must be enlarged to 5 or 5.5 mm and is likely to require one stitch.
"The procedure itself takes just 10 to 15 minutes, and patients generally are
back to their normal activities the next day," said Willard Rice, MD, a
board-certified ophthalmologist who performs several hundred of the no-stitch
procedures at UMass Memorial each year. "Prior to phacoemulsification, it would
be two months before a patient's prescription stabilized, with limited bending
and lifting for weeks due to the pressure it exerted on the wound."
IOL technology also continues to improve, eliminating the need for the thick
"coke-bottle" glasses so familiar to postsurgical patients of previous
generations. Like contact lenses and prescription eyeglasses, today's IOLs
differ in refractive power, and preoperative evaluation can determine the
appropriate lens power for the individual patient.
"Because we can calculate the type of lens needed, after surgery many
patients may not need to wear glasses all the time," said Dr. Rice. "And some
patients see even better than they did before they had cataracts."
In addition, new multi-focal IOLs enable patients to see at all distances,
not just one. "The natural lens has the ability to focus at varying distances,"
explained Joseph Williams, MD, PhD, another board-certified ophthalmologist who
performs surgery at UMass Memorial. "After cataract surgery, due to the
inability of some lens implants to adjust focus, if the distance vision was
clear without glasses, the near vision would be blurred, and reading glasses
were required for close work - similar to the presbyopia people experience as
they age. The newer multi-focal IOLs more closely mimic the functionality of the
natural lens and reduce a patient's dependence on eyeglasses," he adds.
Another newer lens implant blocks both ultraviolet and blue light rays, which
research indicates may damage the retina. And some cataract patients with
pre-existing astigmatism may also be candidates for an astigmatism-correcting
intraocular lens, one of the most recent advances in IOLs.
Who is the most appropriate candidate for cataract surgery? Because the
procedure is so safe and effective, it is appropriate for practically anyone
whose vision is affected by the disease.
"We generally recommend that cataracts be removed when they begin to
interfere with a patient's normal activities, such as driving," said Dr.
Williams. Other patients may need cataracts removed for medical reasons, for
example, if a patient has diabetes and the cataract is interfering with the
ophthalmologist's examination of the retina.
While no-stitch cataract surgery is the most frequently performed ophthalmic
surgical procedure at UMass Memorial, a full range of medical and surgical
services to improve vision is available including LASIK surgery,
ocuplastics/orbit/ocular oncology, neuro-ophthalmology, pediatric ophthalmology
and vitreo-retinal ophthalmology.