Laser keloid scar removal -A Cutting Edge Approach
Keloids are the result of an overgrowth of dense fibrous tissue that usually develops after healing of a skin injury. The tissue extends beyond the borders of the original wound, does not usually regress spontaneously, and tends to recur after excision. The first description of keloids (recorded on papyrus) concerned surgical techniques used in Egypt in 1700 BCE. Subsequently, in 1806, Alibert used the term cheloide, derived from the Greek chele, or crab's claw, to describe the lateral growth of tissue into unaffected skin.
Treatment:
Despite increasing knowledge of wound healing and collagen metabolism over the past decade, scars and striae have traditionally been difficult lesions to eradicate. The millions of individuals affected by them have had little in the way of viable treatment options from which to choose until the last few years. Prior to the discovery that pulsed dye lasers could be used to safely and effectively treat scars and striae, treatments ranging from invasive surgical excisions and grafting proceduresto dermabrasion, cryotherapy, corticosteroid injections, pressure therapy, and radiation therapy were used with varying degrees of success. Unfortunately, most of these treatments often were of little benefit or had side effects that were nearly as severe as the original scar. Even the use of vaporizing lasers such as the CO2, argon, and neodymium:yttrium-aluminum-garnet (Nd:YAG) led to almost uniform scar recurrences. The more recent introduction of topical treatments, including retinoic acidand silicone gel, has produced waves of enthusiasm, but overall scar or striae effect has been minimal and slow to achieve.Similar results have been reported with the use of other occlusive dressings as well.
Beginning in the late 1980s, experiments using a vascular-specific pulsed dye laser on hypertrophic scars present within port-wine stains were initiated. Early in its use, it became clear that the 585-nm pulsed dye laser could affect more than its intended microvascular target. The laser-treated scars became more pliable and less hypertrophic, erythematous, and pruritic. These clinical observations were later substantiated by skin surface textural analyses, erythema reflectance spectrometry readings, scar height measurements, and pliability scores, all showing significant improvement with one or two laser sessions. Histopathologic examination of laser-irradiated scars confirmed the suspected improvement in dermal collagen (more fine and fibrillar post-laser treatment), but also pointed to a possible etiologic explanation for the laser's effectiveness with the appearance of increased numbers of regional mast cells in the irradiated scars.As histamine has been shown to both positively and negatively affect collagen synthesis, its role in laser-induced scar improvement has yet to be determined. In addition, given the fact that mast cells also elaborate an intriguing variety of cytokines,their presence following laser irradiation and accompanying tissue revascularization may provide an explanation for the therapeutic outcome following microvasculature destruction in terms of stimulating collagen remodeling. Other etiologic mechanisms include the possibility of collagen stimulation by dermal heat conduction from the irradiated blood vessels or lack of tissue oxygenation leading to collagen catabolism and release of collagenase.
Similarly, and perhaps not surprisingly, striae have also shown improvement after 585-nm pulsed dye laser treatment. The fact that striae often demonstrate scar-like features with early erythema and late fibrosis could account for the significant improvement seen in some cases.
Treatment:
Despite increasing knowledge of wound healing and collagen metabolism over the past decade, scars and striae have traditionally been difficult lesions to eradicate. The millions of individuals affected by them have had little in the way of viable treatment options from which to choose until the last few years. Prior to the discovery that pulsed dye lasers could be used to safely and effectively treat scars and striae, treatments ranging from invasive surgical excisions and grafting proceduresto dermabrasion, cryotherapy, corticosteroid injections, pressure therapy, and radiation therapy were used with varying degrees of success. Unfortunately, most of these treatments often were of little benefit or had side effects that were nearly as severe as the original scar. Even the use of vaporizing lasers such as the CO2, argon, and neodymium:yttrium-aluminum-garnet (Nd:YAG) led to almost uniform scar recurrences. The more recent introduction of topical treatments, including retinoic acidand silicone gel, has produced waves of enthusiasm, but overall scar or striae effect has been minimal and slow to achieve.Similar results have been reported with the use of other occlusive dressings as well.
Beginning in the late 1980s, experiments using a vascular-specific pulsed dye laser on hypertrophic scars present within port-wine stains were initiated. Early in its use, it became clear that the 585-nm pulsed dye laser could affect more than its intended microvascular target. The laser-treated scars became more pliable and less hypertrophic, erythematous, and pruritic. These clinical observations were later substantiated by skin surface textural analyses, erythema reflectance spectrometry readings, scar height measurements, and pliability scores, all showing significant improvement with one or two laser sessions. Histopathologic examination of laser-irradiated scars confirmed the suspected improvement in dermal collagen (more fine and fibrillar post-laser treatment), but also pointed to a possible etiologic explanation for the laser's effectiveness with the appearance of increased numbers of regional mast cells in the irradiated scars.As histamine has been shown to both positively and negatively affect collagen synthesis, its role in laser-induced scar improvement has yet to be determined. In addition, given the fact that mast cells also elaborate an intriguing variety of cytokines,their presence following laser irradiation and accompanying tissue revascularization may provide an explanation for the therapeutic outcome following microvasculature destruction in terms of stimulating collagen remodeling. Other etiologic mechanisms include the possibility of collagen stimulation by dermal heat conduction from the irradiated blood vessels or lack of tissue oxygenation leading to collagen catabolism and release of collagenase.
Similarly, and perhaps not surprisingly, striae have also shown improvement after 585-nm pulsed dye laser treatment. The fact that striae often demonstrate scar-like features with early erythema and late fibrosis could account for the significant improvement seen in some cases.
