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

Case Overview

Burn injuries are often devastating accidents that result in long-term physical and psychosocial consequences. Burn-related injuries frequently lead to the formation of hypertrophic scars.¹ These scars not only lack aesthetic appeal, but can also cause pruritus, restricted range of motion, and have a negative overall impact on mental health.² Surgical scar removal and contracture release are crucial corrective treatments that require postoperative adjuvant therapies to minimize the risk of recurrence of scar formation.^3, 4 Laser treatment is a low risk minimally invasive approach. Research has shown that laser therapy effectively decreases the thickness of burn scars and alleviates neuropathic pain. Furthermore, it improves pigmentation, texture, height, and itchiness of the scars.⁵

This video discusses the implementation of a laser-based procedure designed for scar remodeling.⁶ The use of a pulsed dye laser (PDL) and fractional ablative CO₂ laser are demonstrated in a pediatric patient who had suffered from burn injuries 7 years ago in Vietnam. 

Starting the treatment session with PDL, the video demonstrates how the specific settings are employed for a patient, emphasizing the importance of fluence (energy delivered per cm²), pulse duration, and cooling settings, along with laser safety measures, including protective eye-wear for both the patient and the healthcare providers. Moist surgical towels are employed around the area of exposure to minimize potential thermal effects on surrounding elements like surgical drapes or hair by the laser and to prevent thermal injuries. Depending on the wavelength, laser waves are selectively absorbed by hemoglobin, oxyhemoglobin, melanin, water, or collagen in the skin.^7, 8 The unique choice of wavelength for the PDL, 595 nm in this case, allows for precise targeting of hemoglobin, a key component in the fine vessels associated with scar formation.

The initial phase involves a test shot with the PDL and a demonstration of immediate response by scarred tissue characterized by a purpuric pattern, which mimics the laser spot in size and shape. Following PDL treatment of skin lesions, in vivo measurements revealed an immediate increase in the optical absorption of blood. This effect, induced by thermal stress, is a consequence of an elevated dermal blood volume fraction and the thermal denaturation of hemoglobin, which leads to the oxidation of its iron atom and the formation of methemoglobin. Methemoglobin is a light-absorbing dark pigment. As a result, the weakened walls of the blood vessels become permeable, leading to the development of petechial hemorrhages, which manifest as dark red-purple discolorations.^9, 10 Appearance of a purpuric pattern confirms the laser's efficacy in targeting hemoglobin within the scar's vasculature. A dynamic cooling device associated with the laser device is utilized synchronously to protect the epidermis throughout the whole procedure by delivering a puff of cool air with every shot.

Upon completion of the PDL treatment on the facial burn scars, the video transitions to the next phase, introducing the fractional ablative CO₂ laser, which is applied to the face and then to the remaining scarred areas on the patient's torso and extremities. The CO₂ laser is used to target tissue water. Owing to skin’s relatively high water content, the CO₂ laser provides ideal precision, achieving a safe ablation with good hemostasis.¹¹ This process aims to create zones of thermal damage, resulting in targeted tissue necrosis, which in turn triggers a rapid response from the body's wound-healing mechanisms. This approach gradually transforms scars, reducing their firmness and height. The approach has been found to be particularly useful for the management of hypertrophic burn scars.¹² Given the sensitivity of facial skin, the fractional CO₂ laser settings must be navigated with caution. Records are maintained for previous treatments, and the device settings are adjusted accordingly. Maintaining a balance between efficacy and safety, the treatment settings are not uniformly applied across all regions. Due to their lower sensitivity, the torso and extremities can be exposed to a higher fluence of energy, along with an increased density and frequency of the laser.

Next, topical Triamcinolone ointment is applied as part of laser-assisted drug delivery to improve the wound-healing process, reduce scar thickness, and alleviate unfavorable responses to laser-induced thermal skin injury.^13,14 The laser-assisted drug delivery may facilitate topical absorption via skin, aiding in optimal scar remodeling.

The residual burn scars on the patient’s torso and the areas previously treated with meshed skin grafts are addressed next. A comparative demonstration using a wooden tongue blade illustrates the impact of varying energy levels on the depth of penetration. A key consideration during the fractional CO₂ laser application is to avoid the overlap between treatment areas. Overlapping edges could lead to micro-areas of over-treatment, potentially resulting in scarring. In order to reduce this risk, small gaps are intentionally kept between treatment sites. This strategy minimizes the likelihood of adverse effects and supports the overall goal of controlled and effective scar remodeling.

The patient's history includes both traditional surgical interventions, such as Z-plasty lengthening, and previous laser treatments. Specific attention is given to cases where functional improvement, such as increased range of motion, is a primary objective. As the treatment progresses to larger surface areas on the torso, the advantages of repeat laser treatments are highlighted, as it shortens general anesthesia time. The increased occurrence of facial bleeding in comparison to the torso areas is attributed to higher density of superficial blood vessels. The demonstration of laser treatment over surgically induced scars showcases the precision and efficacy of the approach. 

The importance of monitoring the patient's growth and adjusting scar treatment accordingly is highlighted, particularly as children approach prepubertal and pubertal years. The difficulty of scars in keeping pace with rapid growth is emphasized by the practitioner, and measures taken to prevent secondary deformities are discussed. The patient's treatment in Vietnam, under the care of experienced laser clinicians, is emphasized to ensure ongoing scar management.

This video provides a detailed exploration of advanced laser therapy in scar management. From targeted treatments for specific scar characteristics to the integration of laser therapy with surgical interventions, the video presents a holistic, patient-centered approach. This approach not only aims for aesthetic improvements but also prioritizes functional outcomes, contributing to overall patient well-being.

Statement of Consent

The parents of the patient referred to in this video have given their informed consent for surgery to be filmed and were aware that information and images will be published online.