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Initial
Tests of Laser Treatment for Presbyopia are Promising
By Nancy
Groves
Reviewed by Sandra Belmont, MD, Colette Cozean, PhD, Bobby
Maddox, MD, James Miller, MD, and Jon Siems, MD
A series of small studies conducted in the United States and
Canada found that most patients who underwent laser presbyopia
reversal (LAPR) had significant clinical improvement and could
read magazines and newspapers without glasses shortly after
surgery.
Scleral ablation was performed with the OptiVision laser treatment
system (SurgiLight Inc.). Using an infrared
laser with a 3-µm wavelength, the surgeon makes eight
external incisions in the sclera to increase the efficiency
of the ciliary muscle. This results in a stronger capacity
of the eye to focus on near objects, said Sandra Belmont,
MD, principal investigator and associate professor of clinical
ophthalmology at Weill Cornell Medical College, New York.
In studies conducted at Weill Cornell and at the Las Vegas
clinic of Jon Siems, MD, all 10 patients were able to read
a newspaper without glasses within 1 or 2 weeks of surgery,
and six of 10 showed successful accommodation, an increase
of 1 to 3 D.
“The results are very promising, and patients are very
happy,” said Dr. Belmont, who treated two patients at
her study site. “They feel like they have a new lease
on life.”
Immediate results
The surgery takes 20 to 30 minutes per eye, and results are
almost immediate. “Patients are able to read without
glasses within an hour,” she said.
Patients with 20/70 or 20/80 vision before surgery achieved
20/25 or 20/20 uncorrected vision. These results were stable
at the 6-week follow-up, Dr. Belmont added.
Dr. Siems has treated eight patients, and all are now free
of glasses for reading. Most have 20/20 or 20/25 visual acuity.
“The results are very impressive and have exceeded my
expectations,” he said. The first two trials in Canada
were in New Westminster, British Columbia, with James Miller,MD,
and in Montreal with Mihai Pop, MD.
The two physicians recently presented data to the Ministry
of Health on 14 patients at 6 months.
At the centers in Canada and the United States, physicians
have been limited to treating patients who have never had
eye surgery and have no significant refractive error. The
eligibility criteria are expected to change in Canada after
additional data are submitted and in the United States once
a second trial is begun.
As of early March, Dr. Miller had treated 11 patients (22
eyes) with the OptiVision laser. Three-month or longer results
are available on eight of the patients.
“The results are encouraging. People are seeing better,
and they’re having some ability to see up close,”
Dr. Miller said. “Improvement is variable. Some people
have had quite a significant
improvement, and some have just a modest improvement, but
all have had some improvement.”
Keep expectations realistic Reasonable goals following surgery
may include being able to read the price tag on items at the
grocery store or reading part of the newspaper under normal
light conditions, Dr.Miller said.
“Some patients do better, but most are able to do that,”
he added. “We’re giving people modest expectations.
We’re not expecting that they are going to function
like when they were 20 and they could accommodate and see
up close. What we’re trying to do is give a bit of near
focus ability.We are encouraged that this is a useful procedure,
but it needs to be worked on further.
“We have not had any regression or serious complications,”
he added, explaining that the complication rate from several
hundred patients in overseas studies over several years has
been low. These included four cases of hypotony that might
have been associated with microperforation, said Colette Cozean,
PhD, SurgiLight chairwoman, CEO, and regulatory consultant.
All healed completely in less than 1 week. More commonly,
patients experienced dry eye and mild irritation or discomfort
that was treated topically. How LAPR is performed LAPR is
not a difficult procedure for experienced eye surgeons, Dr.
Miller said. Using topical anesthesia, the physician makes
four peritomies, and then quickly makes eight incisions or
troughs, two in each quadrant. The troughs begin about 0.5
mm from the limbus and extend radially about 4.5 mm. The troughs
extend through 80% to 90% of the depth of the sclera, stopping
at the blue hue of the choroid. The peritomies are then sealed
and the conjunctiva is replaced over the incision.
“This seems to lessen scleral rigidity, and in some
way that we do not fully understand, it seems to give them
some ability to focus in near.We do not know the exact mechanism,”
Dr.Miller said.
In animal studies, investigators have determined that the
incision takes time to heal because it is wide and the laser
has sealed the endings. During that time, the incisions spread
further because of the internal pressure of the eye, reaching
up to 1.2 mm. “Circumferentially around the sclera,
you get about an extra centimeter worth of diameter,”
Dr. Cozean said. “That seems to be enough to allow the
ciliary muscles to have a restoration of their ability to
provide accommodation.”
The average increase in accommodation among all patients treated
with the Opti- Vision system has been 1.9 D, Dr. Cozean said.However,
that increase is not enough to explain the improvements that
some patients have experienced, such as having visual acuity
of 20/200 before surgery and 20/25 afterward.
“A couple of diopters of accommodation are not enough
to do that, but we have not been able to determine what else
is happening,” Dr. Cozean said. In Juarez, Mexico, Bobby
Maddox,
MD, of El Paso, TX, has treated 13 patients (26 eyes) with
the OptiVision system. Results have been “pretty spectacular,”
with all but two now reading an average of J2 (20/30), which
is the size of telephone book print, Dr. Maddox said. One
patient experienced no improvement, while a second has intermediate
vision and is able to read materials at arm’s length.
With three patients at 6 months postoperatively and the others
at 3 to 4 months, there have been no signs of regression.
Data on 300 eyes from studies outside the United States have
been submitted to the FDA, Dr. Cozean said. Results have been
fairly consistent across the multiple sites, with only a few
outliers.
Only one patient had improvement then regression over a 9-month
period since all sites began following the same protocol,
and two did not have as much improvement as initially thought.
While they have seen no significant regression at 2.5 years,
a degree of regression is likely for many patients as they
age. “I think we are going to see regression but probably
more due to the nature of the disease than to the procedure
itself, based on the permanent ingrowth of tissue,”
Dr. Cozean said. However, she added that there is no reason
to believe at this time that patients could not receive periodic
surgical touch-ups. The FDA has not approved the Opti-
Vision system for LAPR, although the technology is being used
in other countries.
More extensive trials are planned in the United States and
Canada, pending regulatory approval.
None of the doctors has a financial relationship with
SurgiLight, except for Dr. Cozean. The doctors are
purchasing their own systems for the clinical trials.
Web-site: www.surgilight.com,
email: surgilightsales@aol.com
For Additional Information Contact:
©Reprinted from OPHTHALMOLOGY TIMES, September 1, 2003
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