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Erasing Skin Marks with Lasers
by Ricki Lewis, Ph.D.
Port-wine stains can make life difficult for people of all ages.
Donna
Arnds, a 23-year-old from north Los Angeles, has marks on her nose,
eyelids
and lips. In high school, she never attended a dance because, she
says, no
one wanted to be seen with her. Anne Plescia, 40, of Ithaca, N.Y.,
was often
mistaken to be mentally retarded because of her facial birthmarks.
"I've
been in conversations where they will only address my husband, assuming
I
have no intellect," she says.
Thousands of parents have agonized as their birthmarked children
approach
school age "when the kids are old enough to be cruel,"
notes Linda Margalith
of Beverly Hills, Calif., mother of 3-year-old Alexa.
For Gina Brass of Escondito, Calif., the suffering was even worse.
Many
people who saw the marks on her 6-year-old daughter's cheek and
chin would
accuse her of physically abusing the child, causing her "bruises."
These and
many other people with birthmarks have been helped by a new type
of
treatment using laser devices, which are regulated by the Food and
Drug
Administration. The treatments for benign (noncancerous) skin lesions
possible with lasers extend beyond birthmarks, to include liver
spots,
spider veins, residual redness following plastic surgery on the
nose, and
even tattoo> removal.
The temporary redness, swelling, and a bruised appearance that
can occur
after laser treatment of the skin are preferred by some patients
to the
discomforts of older methods, which include freezing tissue with
liquid
nitrogen, electrosurgery, scraping off (curettage) the affected
area,
treating the area with chemicals such as Retin A (tretinoin) or
acids, or
masking marks with make-up. When used by physicians who are trained
in the
use of a laser, results can be quite dramatic. But in less well-trained
hands, a laser can cause damage and scarring, just as traditional
surgery or
scraping can.
Lasers used in these treatments include: carbon dioxide, argon,
continuous
tunable dye, ruby, copper vapor, and flashlamp-pumped pulsed dye
(see
accompanying article). Here is a rundown on what these new lasers
can do
when applied to the skin.
Port-Wine Stains
A beet-colored mark splashed across a small face can be the butt
of many
children's jokes.
"Reaction depends on the individual child, but especially
when one hits
school age, the teasing is unbelievable," says Tina Dawn, president
of the
National Congenital Port-Wine Stain Foundation in New York City.
"I've known
children to throw their eyes out of whack because they constantly
keep their
heads down to hide the stain," she adds. For these children,
successful
treatment can literally turn their lives around.
Because the idea of a laser can be frightening, the staff at the
University
of Massachusetts Medical Center in Boston gives each patient a Raggedy
Ann
or Raggedy Andy doll that has a matching mark made in red crayon.
The doll
receives a laser treatment to show the child how the mark disappears,
and to
quiet fears.
To remove a port-wine stain, a small area on the patient's arm
is first
tested, and then the mark is treated. Anesthesia is not used unless
the area
to be treated is extensive, and then local anesthesia is used.
The laser feels like a small rubber band being snapped against
the skin. For
the first 24 hours, the area swells and reddens, the signs of the
body's
immune response to the vaporized blood vessels in the birthmark.
The area
turns a bluish-gray with purplish-red spots for 7 to 10 days. The
spots
fade, and the treated area continues to lighten over the next eight
weeks.
But it may be difficult to locate a physician who is experienced
with this
relatively new procedure. "The average dermatologist has yet
to have a laser
available, but more and more are getting them, says Dawn. "Now,
only
specialized medical centers and some dermatologists have them."
Using the flashlamp-pumped pulsed dye laser to treat port-wine
stains
requires more sessions to fade the mark than with other lasers,
and bumpy
lesions do not respond well.
Still, this type of laser is currently the one recommended to treat
children--and the sooner the lesion is treated, the better the results.
Blas
Reyes, M.D., and Roy Geronemus, M.D., of the New York University
Medical
Center, treated port-wine stains in 73 patients between the ages
of 3 months
and 14 years, and discovered three reasons to zap a port-wine stain
as soon
as possible:
- the skin thickens up to age 20, when it becomes more difficult
to treat
- the extraneous blood vessels are smaller in diameter in a youngster
- the stain itself occupies a smaller area in the young.
Spots, Freckles, Moles, and Spiders
A cousin to the "vascular lesion laser" used to treat
port-wine stains is a
pigmented lesion laser, which FDA cleared for use in May 1991. It
is used to
treat lentigines (also known as age, sun or liver spots), moles,
freckles,
and brown birthmarks, which millions of people have. This laser
zeroes in on
melanin, the pigment found in the epidermis, the outer skin layer.
The pulse delivered by the pigmented lesion laser lasts one-third
of a
millionth of a second, and covers an area the size of a pea. It,
too, feels
like a rubber band snap. Two weeks after treatment, the skin peels
away and
is replaced from beneath with a new, unblemished epidermis.
"Many people develop solar lentigines early in adult life,
particularly
people from the Southwest. Not only are these lesions unsightly,
but they
are associated with old age. Removing the lesions seems to enhance
people's
self-confidence significantly," says Joseph Morelli, M.D.,
assistant
professor of dermatology and pediatrics at the University of Colorado
School
of Medicine in Denver.
Too much sun is linked to a number of types of skin lesions. "Exposure
to
the sun thins the skin, making it more transparent. It also causes
enlargement of the blood vessels on the skin's surface, which in
turn makes
these vessels more visible. Plastic surgeons refer to these red,
unsightly
vessels as telangiectasias, or 'spiders'," says Joel M. Noe,
M.D., assistant
professor of plastic and reconstructive surgery at Harvard Medical
School.
Often, spiders are caused by chronic overexposure to the sun, but
they may
also result from liver disease or occur in pregnancy due to a change
in the
way the body processes estrogen. In addition, they can be a side
effect of
oral contraceptives or prolonged use of topical corticosteroid drugs.
They
may also occur with a little-understood condition called rosacea,
in which
the middle third of the face is affected.
"These conditions responsible for red blood vessels on the
face are
incredibly common in our society, especially among the fair-skinned
who have
had lots of sun exposure," Noe adds.
He uses argon or pulsed dye lasers to treat spiders. "It can
be done in the
doctor's office using local anesthesia. The treatment produces a
mild
sensation of heat and a feeling like pinpoints lightly touching
the skin,"
he says. Usually one or two treatments are needed.
Ultraviolet exposure from excessive sunning can wreak havoc on
recovery from
plastic surgery on the nose, producing redness called "post-rhinoplasty
red
nose" as new blood vessels appear on the bridge of the nose.
This is part of
the healing process and is preventable by minimizing sun exposure.
It can be
covered with make-up, or treated with an argon laser, says Noe.
Bleaching Cream Backfires
A 53-year-old black woman had used an over-the-counter "skin
whitener cream"
to even out her complexion for three months when she noticed just
the
opposite effect--a sooty, bluish-black raised area on her face.
Her doctors
first tried to lighten the area by treatments with the acne drug
Retin-A,
cryosurgery with liquid nitrogen, and finally by peeling off the
skin
pigment with trichloroacetic acid. These dermabrasion procedures
worked on
parts of her face, but not on the thin-skinned areas near her eyes
and nose.
She consulted Edgar Smith, M.D., and his colleagues at the University
of
Texas Medical Branch in Galveston, who had reported success with
a carbon
dioxide laser.
Sooty marks resulting from lightening creams are due to the ingredient
hydroquinone, which can cause pigmented fibers to be gradually laid
down in
the dermis (the underlying skin layer). In the mid 1970s, doctors
in South
Africa began reporting the mysterious dark spots on the faces of
black
people who had used products containing 6 to 8 percent hydroquinone,
and, as
a result, the amount was limited in many countries, including the
United
States, to 2 percent. Still, in the 1980s, cases were reported among
U.S.
blacks.
So far only blacks have been reported to be affected, and their
skin
responses range from redness and mild pigmentation, to dark coloration,
to
the appearance of nodules. Although the CO2 laser is now the only
one used
on these blemishes, Smith suggests that a ruby laser may work even
better,
considering the recently reported success of this type of laser
in removing
<tattoos>.
<Tattoos> Skidoo
Since 6000 B.C., people have had their skin <tattooed>--and
then later
regretted it. Unfortunately, treatments to remove the marks often
marred the
skin further. Ronald Wheeland and co-workers of the University of
California
at Davis reported in the December 1990 Journal of Dermatological
and
Surgical Oncology that a preliminary study indicated treatment with
a ruby
laser to remove <tattoos> is "vastly superior" to
standard methods, such as
dermabrasion and surgical removal.
The ruby laser works much the way the pigmented lesion laser does,
and also
feels like a rubber band snap. The laser light is absorbed by melanin
and
the carbon-based pigments used in <tattoos>. The skin initially
turns white
for 10 to 20 minutes, then swells and turns red, feeling like a
sunburn.
Although the skin stays red for one to three weeks, healing takes
10 to 14
days, and fading continues for months. There are no open wounds.
The
researchers treated 163 <tattoos> on 80 patients and found
that black and blue
<tattoos more than 10 years old responded best to the treatment.
The success of laser surgery in treating benign skin lesions has
encouraged
many people to seek help who would otherwise have relied on disguising
or
hiding their blemishes. Lasers have also helped thousands of others
who were
unhappy with the results of more traditional treatments. In the
future, this
kind of laser surgery may become more common for an increasing number
of
people with problems that are more than skin deep. n
Ricki Lewis, a writer in Scotia, N.Y., teaches biology at the State
University of New York at Albany.
Laser Basics
Since the mid-1960s, lasers have proven to be powerful surgical
tools. The
word "laser" is actually an acronym for "light amplification
by stimulated
emission of radiation," which means that the intense and narrow
beam of
light is of one wavelength. Ordinary "white" sunlight,
in contrast, is a
continuum of light of many wavelengths, corresponding to the colors
of the
spectrum plus the infrared (heat) and ultraviolet wavelengths that
sandwich
them.
A medical laser device includes a source of electricity, mirrors
to direct
the beam, a crystal or gas that is stimulated to emit the light,
and tubing
to deliver the energy. Design of the instrument is tailored to specific
uses.
"The diameter of the light beam is picked to match the diameter
of the area
to be treated," says Joel M. Noe, M.D., assistant professor
of plastic and
reconstructive surgery at Harvard Medical School. "For example,"
he
explains, "to treat a blood vessel 1 millimeter in diameter,
you would use a
1-millimeter handpiece. If the target is a group of vessels, you
would use a
larger diameter handpiece."
About 5 percent of the nation's 10,000 plastic surgeons use lasers,
says Noe.
FDA regulates lasers, including those for medical uses. "FDA
evaluation is
of the device itself. We try to find out if the device to be marketed
is
equivalent to another device on the market. It does not have to
be superior.
We look at safety and efficacy," says Sankar Basu, Ph.D., a
physicist with
FDA's surgical devices evaluation branch.
The radiation a laser emits depends on the chemical through which
it passes.
A carbon dioxide (CO2) laser, for example, emits energy that can
heat water;
it can vaporize watery tissue near the body's surface. In dermatology,
CO2
lasers are used to remove warts, lip lesions, and ingrown toenails.
CO2
lasers, however, have no effect on blood, which permeates tissue
beneath the
skin's outer layer.
The blue-green emission of an argon laser is suited for tissue
with a lush
blood supply. It passes right through watery tissue, but is absorbed
by
hemoglobin, the vibrant red protein in red blood cells that carries
oxygen
to the body's tissues. In a port-wine stain, hemoglobin courses
through the
abnormally numerous blood vessels in the underlying skin layer.
An argon
laser can destroy these extra vessels, lightening the marks in 80
percent of
adult cases. But a child's delicate skin can be badly scarred by
the
powerful argon laser.
A gentler laser for benign skin conditions is a flashlamp-pumped
pulsed dye
laser, which FDA cleared for use in 1987. The device consists of
a dye
(rhodamine in methanol) that is excited by high-intensity flashlamps
to
release photons, which are tiny subatomic packets of light energy.
Like an
argon laser, the wavelength of the pulsed dye laser is absorbed
by
hemoglobin, but it is less powerful. When aimed at the skin, a few
brief
pulses safely zap away the blood vessels. The trick is to apply
the light
pulses faster than the blood vessels can dissipate the heat. A pulse
of this
laser takes 360 to 450 microseconds, and the blood vessels need
about 3
milliseconds (equal to 3000 microseconds) to recover. In contrast,
an argon
laser pulse typically takes five-hundredths of a second, long enough
to
damage much more than the stain, and thereby cause a scar to form.
The ability of the flashlamp-pumped pulsed dye laser to treat port-wine
stains was first reported in the Feb. 16, 1989, New England Journal
of
Medicine by Oon Tian Tan, M.D., and colleagues of the Boston University
Medical Center. Since then, other studies have confirmed their findings--and
approximately 60,000 persons have had their birthmarks removed worldwide,
according to the Candela Laser Corp. in Wayland, Mass., which markets
the
device and keeps track of its use.
--R.L.
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