Fractional Ablation Laser Therapy for Burn Scars
Robert J. Spence, MD with Jill Waibel, MD
Fractional ablative laser therapy for burn scars has received extensive exposure in the national media over the last year. Anyone interested in improving burn scars cannot ignore the story of the Berns triplets, the three attractive 22-year-old young women who were burned in a house fire when they were 1 ½ years old. The Today Show, ABC’s 2020, People magazine, Glamour magazine, and multiple Internet sites have all told the story of how, after 20 years of living with their burn scars, the triplets found dramatic burn scar improvement after being treated with fractional ablative laser.
This has led to a lot of excitement and questions about this form of therapy, particularly from survivors of burn injuries. This article is written to help you understand this form of therapy as it is being applied to burn scars and bring some perspective to where fractional ablation laser therapy stands in its development as a routinely accepted treatment for burn scars. Of particular importance is the emphasis on what we do not know about this therapy, and how more study and experience is required to determine what expectations a burn survivor should have if they were to seek treatment.
NORMAL HEALING AND MATURATION OF BURN SCARS
The amount of burn scarring depends on the depth of the burn injury into the skin. A superficial burn wound heals with re-growth of the superficial skin layer, the epidermis. This results in minimal or no scarring, and with occasional changes in the coloration of the new skin layer. A deeper burn injury destroys the cells in the skin that allow the re-growth of the epidermis. When this happens, the burn wound tends to remain open for a longer period of time but will eventually heal by the laying down of scar and shrinkage of the burn wound. These deeper burn wounds result in severe burn scarring and contractures, the tight scars that restrict the movement of joints and distort the normal position of anatomic structures such as the mouth and eyelids. It is these scars that are long-lasting, often permanent reminders of the dramatic burn experience.
As with all scars, burn scars tend to “fade” with time. Over many months, even in the absence of any of the type of therapy, the red, raised, thick and firm hypertrophic burn scars will improve naturally. They gradually become less red and raised, soften and, in some cases, lengthen as an enzyme in the body called collagenase begins breaking down the burn scar faster than the body makes it. Over this quite considerable length of time after the formation of the original burn scar, collagenase dissolves some of the scar (collagen) molecules even while the body continues to make more scar molecules. There is a gradual cycle of building up of scar and breaking down that occurs simultaneously causing a process called “remodeling” of the scar.
This remodeling process proceeds for years, but the greater part of the process occurs within the first two years after the burn injury and initial scar formation. In some cases, the scars become almost the same color and almost as flat as normal skin, as well as quite soft and pliable. However, most scars maintain some of their unfavorable characteristics, and the scarred skin almost never looks like normal skin again despite the improvement of all these characteristics. Certainly after two years, the very slow improvement of the burn scars and the rate of remodeling become so slow that it is not easily perceived.
HOW DOES FRACTIONAL ABLATION LASER THERAPY WORK?
Laser is a word derived from the following scientific description: Light amplification by stimulated Emission of radiation. In layman’s terms, laser generally refers to light energy of a single frequency of light which is concentrated in a beam. In medicine LASERS are used to create a specific therapeutic response by transforming light into heat. In the case of the burn scar the laser vaporizes the old scar, creates a wound resulting in new healing. Although we generally think in terms of visible light and the different frequencies causing different colors, the light can be anywhere along the electromagnetic spectrum including infrared and ultraviolet..
Depending on the frequency, the light energy is absorbed better by some colors and substances. For example, pulsed dye laser has a 595 (most common used now) nm frequency which is absorbed well by the red color of the hemoglobin in blood. This red color has a frequency of 542 nm.
A laser can either be as harmless as a laser pointer or extremely destructive such as those weapons used for warfare. Its destructiveness depends on how much energy is packed into the laser light; that is, how much it is amplified.
Medical lasers have a moderate amount of energy and, when they are absorbed by tissues, the heat released causes destruction of the tissue absorbing the light. Carbon dioxide laser is absorbed by water in tissues causing damage or vaporization of the tissue depending on the amount of energy in the laser light. Other laser frequencies are good for absorption into tattoo pigments of various colors causing breakdown of the pigment molecules while, at the same time, being absorbed less by the skin tissue, preserving it as much as possible.
Ablation is a term used to describe total removal of the target tissue or substance when the energy of the medical laser is strong enough to vaporize it. The tissue is literally gone. When used in a superficial manner, it can remove layers of skin.This is the basis of some of the aesthetic uses of medical laser. In the face, for example, a laser “peel” of the superficial layer of skin and subsequently healing by regeneration of the epidermis causes the facial skin to be rejuvenated by removing wrinkles and discolorations.
Whereas traditionally, laser light has been delivered as a single beam, recent developments have demonstrated how the laser light can be delivered broken up into multiple small beams. So rather than a single beam, the same amount of energy is delivered “fractionated” into a number of beams collectively called an “array” when each of these themes is exceedingly small, the array is called a “micro-array.”
Fractional ablative laser can best be understood as a beam of light that is broken into a number of tiny laser columns of CO2 laser that drill multiple tiny holes into the tissue at which it is directed. The tissue in which it is directly absorbed is totally ablated resulting in what one can picture as multiple micro-tunnels into the tissues. Surrounding each one of these tunnels there is injured scar from the heat that caused the vaporization of the tissue that used to be in each tunnel. Surrounding the injured scar is normal scar which still remains intact.
The fractional ablative laser treatment therefore results in a new injury to the scar tissue in which some of the scar has been totally removed and some injured. Within these micro-injuries to the scar, all of the previous mechanisms of wound healing and scar maturation begin over again with subsequent new remodeling of a burn scar.We think that this process stimulates new remodeling deep in scars which, in some cases, might have been dormant for years. When this deep fractional ablative laser treatment is combined with the widely used superficial fractional ablative laser resurfacing, not only is the deep portion of the burn scars improved by new remodeling, but the superficial appearance of the scars can be improved as well. We hope that the typical mesh pattern of some skin grafts and burn scars, and possibly even the more prominent hypertrophic scar contour irregularities can be reduced using superficial fractional ablation laser resurfacing.
The combination of both the superficial and deep fractional ablation therapy modes theoretically could result in dramatic changes in burn scar in terms of superficial resurfacing and deeper overall remodeling of the scar.
DOES IT REALLY WORK?
If one were to base one’s judgment of the real effectiveness of this new form of laser therapy on the high profile media reports, and public and private claims of dramatic improvements, the conclusion would be yes, fractional ablative laser treatment works. However, this conclusion may be premature. Responsible reporting of the effects of this type of therapy emphasizes the need for more study in a scientific and controlled manner.
The fact is, at this point in time, although the early results seem to be very promising, we cannot state in a conclusive way that fractional ablative laser therapy works, how well it works, and what one can reasonably expect on a routine basis.
There have been a few early studies reported at meetings showing improvement of scars in most cases. We must await publishing of peerreviewed, scientifically performed studies. Other studies are currently underway.
There are still many very significant questions regarding its effectiveness in new burn scars versus older, more mature burns. Even the various parameters such as laser instrument settings and length of time between treatments have not been conclusively determined to give the most effective clinical result.
WHAT ARE THE COMPLICATIONS? HOW FREQUENT?
The most common side effects after fractional ablative laser treatments are redness and swelling. Typically the redness lasts two weeks to one month. Make-up can be worn within the first week. Skin will feel “dry” 2-4 days after the procedure and resolves with peeling. Peeling is expected and occurs 5-7 days after the procedure.
Itching occurs as part of normal healing, but also could be part of a complication such as infection, poor wound healing, and allergic skin reaction. Most patients experience minimal to no post-operative pain. Strict sun avoidance and sun protection for one month after the treatment is very important to avoid pigmentary changes.
Because of the very small wound created from the fractional laser the skin re-epithelizes (the thin top layer of skin regrows) in 48 hours. This significantly reduces the risk of infection. After any laser treatment risks may exist from bacterial, viral or fungal. Most patients are placed on prophylactic antibiotics one night prior to procedure and six days after. Signs to watch for include fever > 100.4 or above, yellow/white discharge, pain, itching. If any of these occur, patients need culture and appropriate therapy.
PROLONGED WOULD HELAING, NEW SCARRING, HYPOPIGMENTATION/UNFAVORABLE COLOR CHANGES?
There have been reports in the literature of cosmetic patients who develop scars after fractional ablative laser therapy, but thus far no reports of worsening of scars with this class of laser. Delayed hypopigmentation as seen with traditional carbon dioxide and erbium laser have not been seen with fractional ablative lasers.
HOW IS IT DIFFERNET THAN PULSED DYE LASER THERAPY?
Pulse dye laser therapy is the other form of laser therapy that is commonly used for burn scars. It is not fractionated into multiple columns of light as is fractional ablation laser therapy. “Pulse dye” it is simply the term that is used to describe a particular laser that delivers a single beam of light with a wavelength of 585 nm. Because this frequency of light is absorbed well by the red hemoglobin in red blood cells, it seems to be most effective for red, immature scars. It is thought that the energy from the pulsed dye laser light is absorbed by the hemoglobin and the resulting heat damages the numerous blood vessels in the immature scars. It seems that this therapy tends to make immature,red scars become less red and also causes them to mature quickly in terms of reduction of size, firmness, and making them less pruritic (that is, less “itchy”). Currently, pulsed dye laser therapy for burn scars is much more commonly paid for by health insurance than fractional ablation laser.
HOW MUCH DOES IT COST?
Treatments costs depend on the size of the scar and whether the scar can be treated in an office setting or an operating room with anesthesia/sedation is required. Treatments done in the office typically range from $500 to $3000 depending on body surface.
DOES INSURANCE PAY FOR IT?
At this point in time, fractional ablation laser therapy has not been so well established as an effective clinical treatment of burn scars that insurance companies pay for the treatment on a routine basis.
We are currently working with the AMA coding committee to establish codes to pay for these treatments. We encourage patients to contact their insurance company prior to treatment to see if their individual plan may cover. We will keep you posted on our efforts in Washington.
Robert J. Spence, M.D. is an American Board of Plastic Surgery certified plastic surgeon. He is currently Director of the National Burn Reconstruction Center at Good Samaritan Hospital in Baltimore, MD. He is the former director of the Johns Hopkins Burn Center and the Johns Hopkins Center for Burn Reconstruction.
Jill Waibel, M.D. is an American Board of Dermatology certified dermatologist in private practice in Miami, FL. She is recognized as the foremost clinical authority on the use of factional ablative laser therapy for burn scars.