A U.S. dermatologist shares his experience working with a Chinese plastic surgeon who does a high-volume of scar treatments.
Dr. GoldMichael H. Gold, M.D., medical director of the Gold Skin Care Center and Tennessee Clinical Research Center, in Nashville, Tenn., has several academic appointments in China. He has traveled to China on a regular basis for the past 13 years to work with and teach dermatologists and plastic surgeons there who treat primarily burns and traumatic scars.
“They call it teaching; I call it learning,” Dr. Gold says.
He says, the sheer volume of work the Chinese do on scars puts them at a high skill level. While high-volume dermatology clinics in the U.S. might encounter 100 or 200 patients a day, the clinics and hospitals that he goes to in China might see 2,000 or 3,000 patients daily.
In China, patients have access to as much technology as is available to providers who treat scars in the U.S. Like in the U.S., the gold standard technology for scar treatment is the pulsed dye laser, (V Beam Perfecta, Syneron-Candela) and the fractional CO2 laser, most commonly UltraPulse (Lumenis), according to Dr. Gold.
Dr. TanDr. Gold says he has had the pleasure of working with a plastic surgeon in China, who is known as Dr. Scar, a nickname earned for his high level of experience and skills treating burns and traumatic scars. Jun Tan, M.D., is director of the department of plastic surgery and the Laser Aesthetic Center at a hospital affiliated with the Hospital of Hunan Normal University, Chang-sha city, Hunan Province, China. Among many professional and academic appointments, Dr. Tan is chairman-elect of the Chinese Society for Scar Medicine. In the last two years, Dr. Tan has treated more than 1600 patients for scarring.
Dr. Tan’s work, according to Dr. Gold, is based on the teachings of Jill Waibel, M.D., a U.S. dermatologist who pioneered hypertrophic scar fractional CO2 laser research. [LINK TO http://dermatologytimes.modernmedicine.com/dermatology-times/news/help-patients-life-altering-scars]
Dr. Tan tells Dermatology Times that he primarily uses three kinds of lasers to treat scars in clinical practice: the ablative fractional CO2 laser (Encore UltraPulse, Lumenis); pulsed dye laser (PDL, 595nm, Candela); and Lumenis One (Optimal Pulse Technology, 500-1200nm, Lumenis).
“Sometimes, we use Q-switch laser (Q1064nm, MedliteC6, Hoya ConBio) to treat tattoo scars,” he says.
Dr. Tan says he uses these devices given his understanding of laser technology principles, scar histological types and characteristics, and post-laser wound healing management.
What’s especially important when treating scars, he says, is knowledge of how deeply to drill into the targeted tissue with an ablative laser.
“… the level is reached by heat, resulting in a heat-mediated inflammatory reaction to induce the tissue regenerative process, including of collagen remodeling,” according to Dr. Tan.
Histological changes to scar tissue can’t take place if there isn’t enough thermal damage. One of the challenges with treating scars is penetration depth from PDL and fraction CO2 are limited. Even Scaar FX (Lumenis), which has the deepest penetration currently on the market at a maximum of 6 mm falls short for scars that have a thickness of more than 10 mm, he says.
Dr. Tan says it’s important to consider the histological characteristics of erythematous scars early on. In the early stages, they’re superficial with an atrophic epithelium; deep angiectasis, with few collagenous fibers and a lot of connective tissue proliferation; and inflammatory cell infiltration.
Histological characteristics of older hypertrophic scars include those that are proliferous, with intense fibroblast activity and deposit collagen at a 1:3 ratio--changed from a 4:1 ratio.
The mechanism of PDL for erythematous scar treatment is selective destruction of scar microvasculature through the process of targeted photothermolysis, without inducing more scarring, he says. Another mechanism of PDL use is decreased cellular activity, which results from laser-induced anoxia or through collagenolysis by stimulation of cytokine release.
The mechanism of use for the fractional CO2 laser in hypertrophic scar treatment is to directly remove scar tissue, destroy blood vessels within a scar, restrict collagen synthesis, apoptosis-induction, and create a heat-mediated inflammatory reaction. The reaction, according to Dr. Tan, induces collagen reformation, restarts the tissue regeneration process and results in the formation of healthier “new skin.”
Next: Treating scars with lasers
Dr. Tan, who says he has no conflicts with laser companies, uses the Encore UltraPulse CO2 laser system, which has four handpieces: Active FX, Deep FX, Scaar FX and Ultrapulse CO2. In general, he uses the Active FX for pigmental treatment; Deep FX and Scaar FX for improving scar texture; and UltraPulse CO2 for releasing scar contracture.
“First, we choose the suitable laser based on the color and thickness of scar. Generally, [scar] color divided into four types, i.e.: erythema, hyperpigmentation, hypopigmentation and depigmentation. [Scar] thickness is divided into four types: superficial (flat), hypertrophic, depressed and contracture scar,” he says.
Second, Dr. Tan selects the laser hand-piece and setting parameter to treat scars according to the selective photothermolysis theory, fractional photothermolysis theory and different stages of scars’ pathophysiological characteristics.
“…to treat an erythematous hypertrophic scar, I select a PDL to treat the dilated capillary vessels and fractional CO2 to treat the proliferating fibroblast and deposit collagen,” he says. “Normally, we combine PDL with fractional CO2 laser in the same treatment session. We usually [apply a] cold compress 15 minutes [before starting] the second laser treatment, to avoid unnecessary thermal accumulation.”
Dr. Tan says he uses the Optimal Pulse Technology (OPT) of 500-1200nm (Lumenis) when the capillary vessels within scar are small, and the scar looks pale red or includes post-inflammatory hyperpigmentation (PIH). He says that using a strong PDL in this situation, results in the target tissue being unable to absorb sufficient heat and leads to surrounding tissue getting too much thermal damage.
“So, the smart selection is to use a mild OPT 590nm filter to treat pale red scar or combined with PIH scar. In clinic, most red acne scars be treated by OPT with excellent results,” he says.
Top tips for dermatologist colleagues
Dr. Tan says dermatologists and others treating scars should have a good understanding of the scar repair pathway and suitable post laser wound care.
“Basically, the classical theory for laser scar revision is based on ‘selective photothermolysis’ and it is believed that laser scar revision results in ‘collagen remodeling,’” he says.
While the basic theory is correct, it doesn’t explain how scar tissue turns into healthier tissue--even normal skin.
“We have confirmed that the fractioned CO2 laser’s thermal penetration reaches the depth of dermal layer, and that the heat-mediated inflammatory reaction induces the tissue regenerative process, including collagen remodeling,” according to Dr. Tan.
He says, on the other hand, for scar tissue to change to healthier tissue after heat injury, ‘seed cells’ must exist in scar tissue. He and his colleagues have found that epidermal stem cells and skin appendages remain within scars.
“We surmise that dermal stem cells take part in the tissue regenerative process,” he says.
As for post-laser wound care, Dr. Tan says that most physicians focus on laser parameters clinically, but they do not pay enough attention to the post-laser wound healing care.
“In my opinion, the laser wound healing management is more important than parameters used. We use moist expose burn technique (MEBT), keeping the wound moist. Then, [we use] tissue culture in situ within a simulated moist physiological environment,” Dr. Tan says.
According to Dr. Tan, it’s important to avoid excessive treatment.
Generally, scar wound healing occurs within two weeks after laser treatment. If healing time takes longer, the physician should consider that the laser parameter setting need to be adjusted and whether the wound healing care is appropriate, according to Dr. Tan.
Wound healing, in general, requires six to eight weeks, so clinicians should take sufficient time to let the thermal-damaged scar tissue reform. Dr. Tan says, that in his clinical experience the regeneration process of scar tissue is very slow. That’s especially true for hypertrophic scars, because the primary injury can negatively impact the scar’s regenerative capacity. He recommends that patients have laser treatments at intervals of at least three months and that those with old hypertrophic scars to come back more than six months after treatment.
“The incredible work of Dr. Tan and his colleagues has helped change the lives of countless patients, and this is what we are all about,” Dr. Gold says.
Dr. Gold - Dr. Gold is a consultant for Aerolase, Alma Lasers, EndyMed, Lumenis, Syneron-Candela and Thermi Aesthetics.
Dr. Tan – Dr. Tan reports no relevant financial interests.