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Pulsed Dye and Fractional CO2 Laser Therapy for Treatment of Burn Scars

Branko Bojovic, MD1; Robert Dabek, MD2; Harrison McUmber3

1Shriners Hospitals for Children - Boston
2Massachusetts General Hospital
3Tufts University School of Medicine

Transcription

CHAPTER 1

So this is a pulsed dye laser, it's actually a very commonly used laser for many dermatologic and plastic surgery-related indications. This is unique, because of the fact that we, we have the opportunity to use- this to target a specific target for what we're treating, and that is actually hemoglobin. This laser has a wavelength of 595 nm, and by using different energies and manipulating some of the settings on this, we can actually target into treating some of the very fine vessels that we see typically in hypertrophic scarring. And what that does is, allows us to be very specific in terms of how we can essentially target those vessels, and allow some of the redness in these scars, or the erythema of these scars, to improve. In the past, and when I was in training in the late 2000's, this was probably the exclusive laser that we used at Shriners Hospitals for Children. And then in the- around 2010, 2011, we then went ahead and ended up, being able to start using another laser, which you see next to me, which was the fractional ablative CO2 laser. I'll go over that in a little bit of detail when we use it, but basically, for our patient, based on her physical examination, the amount of scarring that she has, the amount of redness that she has, these settings, in terms of the fluence, which is the energy, 8.5 J/cm2, the pulse duration, as well as some of the cooling settings we have on here, including the hand-piece, which has a seven mm, circular-diameter hand-piece. These are all reasonable settings to consider using for her. And so, what we'll do is we'll go ahead and calibrate this again and then we'll go ahead and, go up to her face to show you the areas that I intend to treat. All right, so, as it relates to the scarring that we have here, she has a combination of different things within her, her scar that are remarkable. The first thing is that you can see these little vessels, and if I press with my finger, you'll see me- able to sort of be- make it blanch, and then you'll basically see those vessels come back into play. And if we go ahead and do that again, and we count how long it takes. One 1000, two 1000, three 1000, that's less than a 3 second refill phenomenon, which for this laser, is a good indication that this will work pretty well. These little vessels are in response to the scar formation that she's had here, and as you can see, they impart a redder hue on her scar, and so, if we can- if we can target these vessels pretty exclusively, and dial into this as we- as I discuss a little bit with the laser, we can essentially get rid of this redness and allow these vessels to essentially ablate, because of the target hemoglobin, which is obviously within the blood within these vessels. And so, what we can do is, we can be very specific and essentially treat some of the redness of these scars very specifically, and then on- at the same time, we can use our fractional ablative CO2 laser to then go ahead and ablate the other areas of the scar in which its target is water. And so, we can work on different levels essentially to, to offer ways that we can remodel these scars, and in turn, turn on the body's wound-healing mechanisms, so that these scars can then undergo essentially a regenerative process, through a controlled injury, particularly thermal injury with our laser choices that we'll use. So, as you can also see here, the most important thing, that should probably be commented on, anytime we use a laser, we have appropriate laser protective eye-wear for the patient, as well as for all of those present in the operating theater. We have moist surgical towels around the area to limit any thermal effects that the laser may have on other things such as surgical drapes or hair, so on and so forth, so that we keep the risk of any fires to a minimum, obviously, and we never want to have that, that's a, that's a completely unacceptable event. So, fires, fire and laser safety for us is really paramount, as is wearing appropriate eye-wear for the laser chosen. So for this laser, we have specific goggles that we're going to use, that we will use, and then when we switch over to our fractional CO2 laser, we're going to switch over to a different pair of goggles that are specific for the wavelength of light that we are using. So, what we'll do now is we'll do a few test shots with the settings that I picked. If it looks appropriate, then we'll go ahead and treat the patient's face. And we're going to focus on her face today only with the pulsed dye laser because this is again, where she has multiple areas of redness that I think we can work on, and the remaining areas of scarring that she has on her torso, extremities, will be really a better modality for the fractional CO2 laser, and the- what we're trying to get here is a little bit of a purple, purpley-red response, which shows that the laser has been able to target its- its hemoglobin chromophore, and essentially cause a- what's called a purpuric response, which shows that there's a- an effect, and we can see that pretty much immediately. And we're going to do a little test shot here, and just make sure it's working. Okay.

CHAPTER 2

So, we're gonna do a test shot here with the settings that I dialed into the laser, and we're going to basically kind of go right here where it's pretty obvious. So we'll count to 3- 1, 2, 3. And so, what you should be able to see pretty quickly is, you'll see a- sort of a circular pattern of the- of the guide that we picked, which was a seven mm hand-piece. And you can pretty clearly see here, there's a- basically, almost like a little early black-blue, or what we in a more appropriate terminology, call a purpuric response. And that's essentially what we're looking for, that means that this area, based on its target, has essentially accomplished what it needs to accomplish, and we can dial this up or down depending on the response that we want. I think for her and for the response that we've seen, and the fact that she hasn't been recently treated with our pulsed dye laser in this area, I think this is entirely reasonable, and we can probably continue to treat the rest of her face at this setting. And what you'll see in time as we finish the case, if we were to just only do the pulsed dye laser- I'm sorry, the- yeah, the pulsed dye laser, you'd actually see this get a little bit more darker towards the end of the case, which shows it's an evolving phenomenon, but an immediate response like this is essentially a very nice target end-point. And so we'll go ahead and treat the right side of her face, then the left side of her face, And then we'll go over this with our fractional CO2 laser, and then treat the rest of her torso and extremities with that as well. All right, so we're just going to go ahead and just continue to treat here. We will overlap minimally, but just a little bit, so that we don't get this non-treatment phenomenon, so what we call these little halos around certain areas. And what I like to do is, I'll just basically start at an area where I did my test site, and I'll just work my way to keep myself along the scar, and then to treat everything as thoroughly as I can.

So, here we go- 1, 2, 3- 1, 2, 3, and we'll go like this, so on and so forth, for the whole scar area. The sound that you hear, sort of a little bit of a splashing here, is a dynamic cooling device that's associated with this, so as this area's being treated, there's a puff of cool air delivered here, so that it basically keeps this area on the surface of the skin and the epidermis, as protected as possible from any thermal injuries as a result of this. And that's a very consistent thing that we do with this laser. There are some indications where you wouldn't use that dynamic cooling device setting, and that's a little bit- complicated to get into details now, but that would basically be for a scenario where you really want to get a significant heat-sync effect for the area that you're treating, in particularly if you're trying to treat areas that you think are a little bit deeper within the scar. But you have to be very careful with that, even in those settings, you typically want to use some type of skin-cooling device, just to keep the area as protected as possible. And you can see this goes pretty expeditiously. In some areas where the redness is more, you'll see more of a purpuric response. And in some areas where the redness is less, you'll see less, which is essentially showing you the specificity of this laser, which is fantastic. And so you can basically, see, if we take a pause here, it should be pretty obvious that I've treated basically from this line where I started with my test site, towards the patient's ear, and you can sort of, just in general, see an overall darker hue, a little bit more of a black-and-blue appearance. And that's essentially exactly what we're looking for. So we're basically going to continue and move over to the chin, and then we'll complete our treatment on the, on the patient's left side, and then once we're done with that, and we're satisfied, we're going to go on to our fractional CO2 laser. So, we'll just continue here, moving our way medially now, up to her chin and then ultimately over to the left side of her face. And we're going to just adjust position now, so we can see the other side here. And what I'm going to do- we're going to put our laser in standby mode, anytime we change position, we always go into standby mode for maximal safety, and I'm just going to go on the other side of the patient, so that I have a better target.

And as you can see, her scarring on the left side is a little bit less involved than on the- on her right. So we have less surface area to treat, but that doesn't necessarily make it any less important. As long as those criteria that I talked about at the beginning of the case are fulfilled, we can use this to treat any size scar on any anatomic site pretty much with the appropriate settings. So basically, you'll see me switch hands here, I like to just sort of keep a hand free sometimes, just to control the area that I'm working on, so as you can see, I can move her head back and forth, so that this way, I don't have to really change much with the laser hand-piece, other than pronating and supinating my wrist. So, we'll go ahead and we'll continue here. This allows me to basically also not have to manipulate the patient much either. These hand-pieces are pretty nice because they're essentially relatively low profile, they allow you to get to certain areas without a lot of difficulty and a lot of ease, essentially. And you can also see here that this treatment area, which is, on her, a fairly sizable amount of her lower face, is something that we can treat pretty expeditiously within about maybe 5 to 7 minutes, we can basically have this whole area treated and completely covered, and then move on to our next treatment. And so that's another great thing about use of this technology. The risk to the patient once all these safety measures are followed is very minimal. It's very fast, and it's actually, when they wake up, noted to have very little pain or discomfort. It's just when these lasers are in use that the actual effect on the skin can really be felt, and that's why in kids, more often than not, we have to put them under an anesthetic, so that they can tolerate that. So, now that we're completed with this treatment, we're gonna put our laser on standby mode, and then we're going to switch over to our fractional CO2 laser and treat the remainder of the face, once again, and then the rest of her torso and extremities that have burn injury, and I'll show you how that laser is different, and how we, choose settings based on her scar burden, and how, how we'll go ahead and treat that area.

CHAPTER 3

We'll get started on this part. So this is our fractional CO2 laser, and the target for this laser is water. So, it's actually- obviously, specific to water, which obviously our body is full of, and so, what this will do is this will actually target the water and ablate it. And in doing so will cause a controlled thermal injury, the nice thing about this is that the areas that it ablates will leave behind, essentially a zone of, of tissue necrosis, which essentially will then very quickly undergo, intervention, on by- by the, by the body's wound-healing mechanisms, and essentially by stimulating the body to do so, there's a controlled wound-healing response that happens, which essentially allows this in a similar fashion to the pulsed dye laser that we had used at the beginning to essentially start the process of wound regeneration, wound remodeling, and essentially starting the healing process,on again, which allows these hypertrophic scars to over time become softer, much more- less firm, certainly less raised and shrink, and essentially causes, really- a very, micro injury that the body can respond to in a controlled fashion as opposed to what a lot of our burn patients have unfortunately been exposed to when they've had their burn injuries, which is a very chaotic wound-healing response because of all the inflammatory and other acute things going on. Now our patient had a burn injury she suffered in Vietnam at the end of July of 2015, and so, she is now numbers of years obviously, just under 4-years-out from her injury. And so, the nice thing about this laser as well as the pulsed dye laser is once the skin that has been affected has epithelialized, or healed over, this- these lasers can be instituted pretty much right away. Now, many people will wait about at least 4 to 6 weeks before they start treating with the laser, but even if patients have had burn scars or other traumatic scars for years, and have never had treatment, they are still going to be excellent candidates. Now because we've treated this patient with our fractional CO2 laser before, we actually have been, keeping track of her settings. And so we use those settings to sort of tell us how much more we can increase our settings, and increase the power we're delivering, or if we need to back off or not. And this prevents us from getting too aggressive or under-aggressive with our treatment. So, currently what this setting is that we have now is called the deep FX, that's unique to this system. And this is essentially going to cause, allow us to create multiple areas of injury, which I'll show you on this wooden tongue blade in a second, based on different densities, different power thresholds, and it'll allow us to essentially create the kind of pattern and injury that we want to the scar so that we can essentially, treat these areas. Areas on the face, particularly, are a little bit more sensitive, and so you have to be a little bit more aware of that. And so, typically some of the settings that we'll use on the torso, and the extremities, will be a little higher than what you'll see on the face and other areas that are around the central face, just to keep that in mind. And so, what we've done from her previous surgery is we've essentially been able to write what her settings were before. And so, what we're gonna do is we're going to go back to those settings, which she tolerated really well, and picking those settings essentially, one thing that we have to take into amount is also the skin types of the patients. And so one thing that we really worry about in this patient who has basically a skin type 4, we want to make sure that we don't treat them too aggressively because one of the side effects can be hyperpigmentation, which ultimately will go away usually after many, many, months, but it can be a very annoying thing to deal with, and so, we don't want to be too aggressive either with the energy that we're using or with the, the amount of the density that we're treating of the surface area. So, based on her previous settings, I'm going to keep those same settings because I was very satisfied with what we had. And so, now that we've dialed in our settings, that's basically the following: 30 mJ, which is the fluence, 5% density, or that's how close the dots that you're going to see are together, and 400 Hz, which is how fast the- this is being laid down. And so we, we can also modify the shape and also the size of what we're lying down. And I'll show you sort of what our typical shape and sizes that we use, which is set at 2 and 10, which is a way that we can essentially manipulate in terms of making it bigger or smaller and also getting different, shapes if we need them, in terms of the different anatomic areas we're treating. So, does everybody have their goggles on?

And so we're going to do a test site like we always do here. And now our laser is in standby mode, we're going to go ahead and put it in ready mode. And so, you'll be able to see here if we do a little test site, this is the pattern that's laid down. And we have our smoke evacuator, because this is ablative, so you'll see some smoke, little columns that are left behind. So we're going to go- 1, 2, 3. You can basically, or should be able to see on the tongue blade, what that looks like. It's about a cm2 surface area. There are many tiny holes that are laid in between those areas. And- I could do another shot with a little higher energy, just to sort of show you the difference between what I've chosen and what a higher energy would do, which would typically cause a deeper penetration into this tongue blade. So let's do that once real quick, and I can show you the difference. We'll go to the maximum on this, which is 50 mJ at this setting. And I'll lay that right down next to it. 1, 2, 3. Sorry- 1, 2, 3. So you should be able to tell the difference, we'll put this on standby mode. You should be able to see the difference, you can see the square that I just put down is a little bit darker, And that's showing that the ablative effect was more, the energy was higher, this actually penetrated deeper down into this tongue blade. And so, you can sort of see the power of this laser in terms of being able to dial different settings for different areas of application. This is particularly important with the scars that we're treating that are of various thicknesses and so forth. And this hand-piece allows us to actually take this setting up to 150 mJ, which is quite high, which can penetrate theoretically up to 4 mm in depth. And so, what we're gonna do on the patient's face because it's obviously a more sensitive area, and we have a baseline that we've used before. We're going to use this first square that I dropped down at 30 mJ, and we're going to treat her facial scars in that area. And then as we go down to the remainder of her torso and extremities, we're actually going to go up to about 60 mJ using the same hand-piece and a little bit of a different software package that allows us, allows us to, to do so. So, now that we've done our test sites, you can see what this looks like. We'll do a test site on the face, make sure that everything looks like it's being tolerated appropriately, and treat that area, and then move on to her torso and extremities. Now that she's been treated with the pulsed dye laser, and as I mentioned before, for the amount of time that we took as a pause, from the completion of that until we start our fractional CO2 laser treatment, you can see more of a response here, more of this sort of black-and-blue, or purpuric, response, which is essentially- shows that this is still in a little bit of evolution. You can actually feel it, it's a little bit warm. And so, that's the heat-sync effect of what's happened. And so, basically, this is a very reasonable response and something that I think is- for her, the settings that we chose, entirely safe, and that she should do quite well with. Now, for this laser, we're going to use a smoke evacuation system, because it is ablative, so it will make micro columns of injury, and, and that ablation will release particulates into the air. So, we want to protect ourselves obviously, as well as the patient, and keep those to a minimum, so we're all wearing very high-filtration level masks, and by using this at the same time, we basically keep those particulates to a minimum. So, it'll be a little bit louder when I use this, and I start treating her face, but essentially, I'm going to follow myself as I treat to take up any of that plume of smoke that's coming off, again, to keep everything as clean from the quality of air standpoint as possible. So we'll go ahead and do a test site here, and we'll turn this on. I'm going to do the test site very close to where I did her previous test site- 1, 2, 3. And I think you should be able to see the pattern that's been laid down, very similar to what we had with the tongue blade. And you can also see a few areas here of bleeding. And so, why that's important is because of the fact that this is going down a certain depth based on the energy I dialed in, into the scar. And those little vessels that were targeted initially by the pulsed dye laser, you saw that there was really no bleeding, what you did see was the aftereffects of that under the surface of the skin, but because this is an ablative laser, what's happening here is that not only did we have ablation of the scar, but any blood vessels that are in that vicinity or, or within the depth of that area, also were affected. And so, you can see that secondary bleeding because we've ablated those areas and caused those, those blood vessels essentially to be affected secondarily. So, the nice thing about this laser is that as a secondary effect, not only are we getting that response that we want in terms of the remodeling and rejuvenation, but we're also going to get a decrease in redness ultimately, because we're also secondarily as a- as an effect of the ablation, we're getting rid of those vessels to a certain degree. So, when we combine these 2 lasers, the pulsed dye and the fractional CO2, we get a very nice additive response, particularly for the redness. Some people would treat her just with the fractional CO2 laser alone, which I have done in the past, but because of some of the areas that she has of residual redness, I thought today, adding the pulsed dye would be a really nice thing to do. Of note, this patient is from Vietnam, as I mentioned, and we have actually a, a well-established, laser-treatment center there that was established by one of our dermatologists, Dr. Richard Rox Anderson. And so, she's going to go back there and continue her treatment. We're going to provide them her records so that they know what settings we've used, what lasers we've used, and so she doesn't have to travel halfway around the world to come and see us, although we're obviously delighted to take care of her, and she'll be able to have excellent care in Vietnam moving forward as they continue to treat her as she grows, to get these scars essentially to improve as much as possible with the technology that we have.

So, what we're going to do now, is we're going to continue the treatment, and we're just going to move along, putting these essential patterns together next to one another- 1, 2, 3. And we'll basically go on in this pathway throughout until we treat everything thoroughly. This laser is also something where you don't necessarily want to overlap these edges, you want them to be as close as they can together, but because it is an ablative laser, any areas where you have laser overlap can be a little bit more obviously treated than otherwise. And so, we don't want to cause a little micro areas of over-treatment, which could lead to scarring, and so we have to be aware of that. As you can see, I leave sometimes a little bit of a gap between the treatment sites, which is entirely fine. I'm gonna go ahead and switch hands here. We're just gonna work our way from the chin over. For this phenomena, it takes them about 2 to 3 days for some of these areas of crusting and, and oozing to go away, and then typically, in about 4 to 7 days, the majority of these areas of treatment have essentially resolved. And so, that's why, from our standpoint, it's another great laser to use, because the downtime is extremely low, and all they typically need on their areas of treatment is just a little bit of Vaseline, Vaseline gauze, and some dry gauze wrapped around it for those first few days. Thereafter, once that's gone by, they can put a moisturizer on there, and they can essentially be treated with sunscreen, and so it's a very low-maintenance treatment modality. And as you can see now, I've really treated this area pretty thoroughly, we'll do one final site here, and you can see a little bit of bleeding here, and essentially that's a very reasonable response that we'll- it's what we like to see. I'm going to go ahead and treat the left side of the face, and then we're going to make our way down onto the torso and extremities.

Okay, and we're going to basically continue where we ended up here, work our way over on the chin. You can also move the hand-piece around, so if I want to modify the direction, I can turn this 90 degrees, so, that I can go from the edge of the affected area into the scar itself, so that I don't overlap into normal skin. That's another technical way to to do this appropriately, so that we don't get these areas treated onto normal skin, which are going to be obviously much more sensitive to this setting, and could lead to things such as burns, hypertrophic scarring, and so on and so forth. So now we've basically treated her whole face with both of the lasers that we are going to use today, the pulsed dye to start off with, and then the fractional ablative CO2. She's had a very nice response. Typically what we do now is over this, we're going to put a- some topical steroid, also known as Kenalog, and we're going to basically allow these holes that we've made to absorb that steroid, and that will essentially have another secondary effect on the wound healing to allow these areas to have less of a robust scarring response. And also, for any areas here that are already thickened, to allow that process to soften up faster.

So, we're going to turn this off, and we'll show you how we apply that, we're going to put our laser on standby. You can sort of see that this is actually quite porous as you can imagine. And so, just a few drops of this actually get absorbed quite well into this area. And so, for her, this is what we're going to do at all the other sites that we treat. This is basically what's essentially known as laser-assisted drug delivery. So, we can make little targeted injuries to the scar, but we can also use this to deliver other drugs, topical vitamins, other, things that are under active investigation now, which we ourselves are looking at and trying to figure out what's best to treat these areas with as an adjunct because now that we've essentially started this wound-healing response, we really want a fertile ground here for this area to remodel and do everything it needs to do, to the best of its capacity, and part of that is providing the right substrate to the wound. The bleeding that you see here and some of that, fluid associated with it, also has, factors in it, and is actually believed to have an effect as well. And so, we just sort of let that stay on there until we do the dressing change, which she's going to leave the operating room with.

And now what we're going to do is now that we've treated her face, we're going to work our way down the torso. As you can see on the torso here, she's had areas of scarring that we've treated here with traditional surgery. She's also been treated elsewhere obviously, when she had her initial injury. She was skin-grafted, and you can see evidence of that. When she arrived here, she had a significant amount of tightness as the arm and the upper arm transitions into her axilla, or armpit region, and then to the upper chest wall. And so one way that we were able to relieve that, you can probably see some of these scars that look like Z's here. We did Z-plasty lengthening, so that essentially, we could take the scar band that she had here and lengthen and narrow it, so that she wasn't restricted and now can have essentially full range of motion of her shoulder. So, a lot of these patients that we take care of from the burn standpoint essentially, are treated with multiple things, including traditional surgery as well as laser surgery. So, it's not uncommon that at any one time we'll do a laser treatment at the end of some of the traditional surgery that we've done, and in fact, that's what we've done for her in the past, we- in the past performed Z-plasty lengthening here to essentially get rid of this constriction band, which is now essentially very soft. And at the end of this procedure, we went ahead and treated her with our laser to essentially get a multi- again, a multi-modal effect for her scarring. And what's important is that, you know, we're treating these patients not just from the standpoint of the appearance of the scar, but also the functional- consequences that these, that these areas of scarring can have on these patients. And so, even though you know, the appearance may be very important, what many of these patients are actually after is an improvement in terms of their functional status, which we've been able to improve quite a bit, and she's very happy with the amount of range of motion she has of her shoulder now. So what we're going to do now is- because we've treated her with our laser, we're going to use the same hand-piece, the same fractional CO2 laser, we're going to change the software a little bit, so we can go a little bit higher on the setting, and essentially we're going to treat it a little bit deeper than her face. Same pattern, same shape, and we're basically going to adjust the density a little bit to a little less dense, which I'll show you on the tongue blade, because we're going with a higher energy, so we want to have some of that dissipation of the heat-sync effect, be a little bit more, in this scenario, again, so we don't get that concern for hypertrophic scarring that's going to- going to respond with a hyperpigmentation response. It's also important too that we are careful with that because we don't want to induce any burns with the laser, and while it's theoretically possible, we've never really had that ever happened to us, but that's because we are very cognizant about some of those things that I mentioned, but that is all tech- also technically possible, so we're gonna make some adjustments to our laser settings, and then we're going to go ahead and treat her arm, forearm, the rest of her torso, and then we're going to work our way down into the thighs where she's had scarring from not only her burn injury, but also some of the donor sites where her skin grafts were taken. What we've done is we've changed the settings a little bit, this is the same hand-piece, known as the DeepFX hand-piece, and we've changed the software to a different software called SCARR FX, which all that means is essentially it allows us to increase the, fluence of energy delivered, so that we can go deeper into the scar, and it's a special software package so that we can get down as far as 4 mm deep in terms of thickness. So what I've done for her is I've increased her fluence from 30 mJ to 60 mJ. I've decreased her density from 5% to 1% and the Hertz rate is maximized on this setting, at 250 Hz. So, essentially I'm going to show you now what that looks like. And just to reorient you, this first square here was the initial setting that I did at 30 mJ. I then went up to 50 mJ just to show the difference and sort of show you how it's a little bit darker and more obvious in this area, with the higher fluence, and right next to the last one, I'm gonna do this current setting, so that you can see what that looks like. Okay. 1, 2, 3. And so, what you should be able to see here is some very, very far away spaced dots. And what that basically allows us to do is go quite deep, but essentially preserve a lot of the skin where the dots are not. You can see that it's unaffected, so that's why these wounds heal so quickly, because there is a fractional delivery of energy as we leave little areas in between where the holes are of normal skin, normal adnexal structures, so that the healing response is much, much faster than a traditional, ablative CO2 laser, which was very popular, in the 80's and 90's, which is much less often used today because of this technology. And just to show you the difference, I'm going to go up on our maximal setting to 150 mJ here, just so you can see how much of a difference that is. This is our highest setting, and what you'll be able to see here- go right next to it. 1, 2, 3. You should be able to see very clearly the difference in terms of the dots. They're much more clear. It's a deeper injury, and it just shows you the way that you can dial in that energy, so it's a similar response to here, where you can see this is darker because of the increase in energy. This is also darker because of the increase in energy because the ablative effect is greater, and it goes deeper into the tongue blade, so, we're going to go back to our 60 setting because that's what we use last time, and she responded well, and we're going to keep our density at 1%. And of note, just as it relates to these settings, this is for this particular laser that we're using here today, which is made by the Lumenis corporation, but these settings are not, to be used across the board. There are many lasers that are out in the market, and so, you have to essentially look at your literature as well as speak with your laser representative, so, that you understand what the different settings on the different lasers are going to mean because they are not uniform across. And so, it's a little bit of a different language, depending on the laser that you're using. But the principles that we're using, the targeted end points that we're looking at is really how we decide what settings ultimately we're going to use.

Okay. I'm going to do a test shot here. 1, 2, 3. All right, and so, what we're going to do now is- because we have a bigger surface area, we're going to basically put the laser on a repeat mode, and I'm going to go very quickly and treat this surface area in a, in a pretty expeditious manner. And what you can see here is, you can see all of the dots that have been laid down, which show the area of injury. And we can basically treat very large surface areas quite quickly when we do this type of setting. As these patients are under general anesthesia, we do want to minimize the amount of time that they are asleep. And so, all of these different laser products that are on the market have the ability to dial in and do things like this so that we can expedite treatment and take care of large surface areas that we see in a lot of our patients. The other thing that's important, you can see this plastic- piece here that essentially allows me to identify the exact focal distance that the beam needs to have. And so, as I go along different parts of the body, I supinate and pronate my wrist to make sure that it stays perpendicular at all times, so that there's no tangential effect, and this essentially goes in at a right angle as it's been designed to do so. And you can see, we've already treated almost all of her torso now. We're going to continue and finish this up. Now, you may ask yourself, why is this area not bleeding like it was on the face? And the reason for that is this has a much less denser network of those blood vessels that are more superficial in this skin, our capillary refill test that we did gives us that inkling, but you'll also notice in some of these areas, you'll see a little bit of bleeding. I probably predict that these areas will bleed a little bit in a response to the laser, so we'll, we'll check on those right now and we'll see if I'm right. 1, 2, 3. And there you go. So, the reason I know that is because you can already see that there's some redness here, and if we do our little test there, you can basically see there is capillary refill, And so this is also going to have a secondary effect of helping these areas that are red essentially become less so as a result of the treatment. And this is also nice because we basically can treat over the scars that we treated surgically. So, any scars that we've induced can be modified really to improve as fast as possible. And the other nice thing is that we're limiting our treatment of the scar to the scar. We're not going outside the borders of the scar, we're not giving the patient additional scarring. And I can also modify the beam too, by just stepping on and off the pedal on my own accord manually, if I want to slow things down, or if I want to do areas that are a little bit more sensitive. And so you should be able to see here that we've been able to essentially treat this entire area in probably just a few minutes. And so, we're going to do the same thing here that we did on the face, we're going to place, at the conclusion of the treatment, we're gonna place our topical steroid, use our laser for our drug delivery method. And we're going to basically treat a few areas here on her arm that are still a little tight. And then we're gonna work our way down onto her thighs.

And so, for a patient like this, this whole surface area can really be treated quite fast, we could many times keep these anesthetics down to well under 30 minutes and treat very large surface areas. Her estimated total body surface area involvement from this injury is about 30% when we add up all the areas that were involved, and so, from our standpoint it's important that we basically try to maximize the results that we can get for them, and I also feel these scars, you can tell where they're a little bit more firm, even though they look a little less red, you still want to treat that, particularly as we go over this joint space here, these areas are always a little bit more prone to being more contracted and firm because of the tension. So, we want to make sure that's not as big of a problem for her as she continues to grow and has long bone growth. And the other thing I will note is that- you can turn our suction off for a second- you can basically see where she's had laser treatment before and you can see some of these areas now where, ultimately, the scarring is so good that she's essentially just got some change in her pigment. There's a little bit of hypopigmentation here, which is not uncommon, but you can essentially appreciate that if we could get the rest of these areas of scar that we treated to look like this, not only will she be functionally in a superb situation, but also from the stigmata of having had a burn, it's not going to be very obvious to people that she had such a significant injury, and that's where the laser I think really helps us in terms of delivering a state of the art option for these patients that wasn't really available to us before. So, we're going to basically work our way down onto the thighs and then we're going to finish up her case.

So as you can see here, this patient has stigmata not of- not only of just some residual burn scar, but you can see where she's had meshed skin graft as well before. And so, we've treated her thighs because of, of those 2 different issues, and she's had a really nice response, so we're going to treat these areas as well. The other thing that you probably can notice is you see some of these strips here of hypo- or dyspigmentation, and this is where she's had previous skin grafts taken from, so you can see what taking a skin graft looks like, it's not a benign thing, although for her, obviously, it was necessary, but you know, taking a skin graft is not without any donor-site, what we call donor-site morbidity. And so, the nice thing about some of the techniques that we use here, particularly, in the Shriners Hospitals for- Hospitals for Children's system is that we can essentially do a lot of treatment of these scars without having to do further releases and grafts, and we can save these very young, otherwise unaffected areas on these young children, the donor-site morbidity of these scars. Now, we can also treat over these scars as well, so that even though they've been essentially used as donor sites, we can actually modify and improve these. One of the harder things to take care of- some of the hypopigmentation, but there are things that are being developed in the lab, particularly here, within the campus that we reside, on ways to manage that as well. So the future looks very bright for taking care of these areas, even if they've been, taken as skin grafts. So we're going to go ahead and treat the thigh real quick. So we're going to basically treat the thighs here and then finish up our case. And as you can see, I have my foot on the pedal here at a repetitive setting, so that we can essentially treat all of these areas quite quickly. And I know that she's tolerated these settings in the past, so I have to do a lot less investigation and test settings, and so forth on her because I know how she's tolerated this, and I followed her in the clinic to see how she does with this. Now, there's a third setting that we can use on these patients that's a more superficial setting, that we're not going to use today for her, but it's a- it's another hand-piece and software setting that allows us to do a more superficial treatment, so that these areas are not penetrating as deep. And that's more for smoothing areas out and blending in certain areas of contour, as well as color variation. And that's a little bit more on a sophisticated level of treatment, but it's another option that we have available to us. And one is she continues to go down the road of her rehabilitation with laser therapy, can be instituted at any time and probably instituted, you know, within the next year or 2 as we get a lot of these hypertrophic areas to essentially go- almost go away. The other thing that's important for her is because she is growing, obviously, we want to keep an eye on these areas of long bone growth, and we want to make sure that we can keep these scars soft and supple as much as possible, so that they will respond to her linear growth, and that she won't have essentially an area of scar contractor that's going to develop as a result of that. So, it's difficult for these scars to keep up with the rapid growth in children, particularly as they get to their prepubertal and pubertal years. And so we want to be very cognizant of that, and it's great that we have this opportunity to treat her in Vietnam, where she can have a very experienced laser clinicians take over her care, and so we can prevent these secondary deformities, as I mentioned, in terms of skin graft need and the traditional releases and grafts that we typically were doing very frequently in the past, to a bare minimum. The other thing that you may see is, you may see me overlap a little bit with this, because the density is at 1%, I have a little bit more ability to, to do that in areas if I've gone by a site that I haven't treated fully, and they tolerate that just fine. And so you can basically see this is- how these areas turn out to look once we've treated them. And it's a- it's a pretty consistent response, they have a little bit of a wheel response, they become red, almost black-and-blue in certain areas where they're- the vessels may be a little bit more superficial in the scar. And essentially, this is what the majority of these patients are going to look like once we've treated them to completion, and a very typical result for this type of a treatment.