Faculty Bibliography

BACKGROUND: Scars have a significant effect on a person's physical and social being. Many treatment modalities for scar improvement such as surgical scar revision, electrosurgical planing, chemical peeling, filler substance implantation, and dermabrasion have been developed. Recently, the resurfacing carbon dioxide (CO2) laser systems have proven to be a useful and safe treatment in the treatment of facial rhytides and acne scarring. OBJECTIVE: The purpose of this study was to evaluate the resurfacing CO2 lasers in the treatment of various surgical, traumatic, acne, and varicella scars. METHODS: Thirty subjects, aging between 14 and 84 years, with surgical, traumatic, acne, or varicella scars were evaluated. Two types of resurfacing laser systems were utilized in this study, a high-energy, short-pulsed CO2 laser and a continuous wave CO2 laser with an optico-mechanical computer flash-scanner. Post-surgical scars were treated with laser resurfacing between 4 and 6 weeks after scar formation. Traumatic, acne, and varicella scars were treated after scar maturation (range, 1-10 years). Scar improvement was evaluated by photographic analysis of before and after images by four independent health care workers using a quartile scale of improvement (< 25%, 25-49%, 50-74%, > 75%) as well as optical profilometry using silicone surface impressions in 12 scars. RESULTS: Twenty of 24 surgical scars had greater than 75% improvement, and 24 of 24 had greater than 50% improvement by photographic analysis. All six traumatic, acne and varicella scars had greater than 50% improvement. Optical profilometry and surface topography maps reveal a significant flattening of related and depressed scars. CONCLUSION: The high-energy, short-pulsed CO2 laser and the continuous wave CO2 laser with flash-scanning attachment are safe and effective as a treatment modality for scar revision. In general, elevated scars improve more dramatically than depressed scars

BACKGROUND AND OBJECTIVE: The objective of this study was to determine the effectiveness of a dynamic cooling device (DCD), spraying the skin with a brief spurt of cryogen prior to the laser pulse, in reducing transient pain associated with 585-nm pulsed dye laser (PDL) treatment of port-wine stains (PWS), and reducing epidermal damage (hypo/hyperpigmentation) caused by this laser during PWS treatment. MATERIALS AND METHODS: Matched treatment sites were compared with and without the use of the cryogen spray in 47 patients at two investigational sites. Pain ratings, clearance of the PWS, and pigmentation changes were assessed. The results were analyzed by skin type and patient age. RESULTS: A statistically significant reduction in pain ratings was found in all patient groups using the DCD without changing the efficacy of PWS clearance. Pain reduction was most remarkable in patients with darker skin types. Dynamic cooling prevented the occurrence of epidermal damage or pigmentation change in most cases. CONCLUSIONS: This study suggests that dynamic cooling can dramatically diminish pain during PWS treatment with the 585-nm PDL without reducing treatment efficacy. The absence of epidermal damage in most patients suggests that precooling with the DCD may allow the use of higher laser fluences to expedite clearance without inducing epidermal change. Dynamic cooling has potential use with other lasers and different lesions where discomfort and epidermal effects limit therapy

BACKGROUND: Carbon dioxide (CO2) laser resurfacing has become a very popular method of rhytide and scar removal in the recent past. Preliminary studies have been published describing the method, histology, and clinical results of CO2 laser resurfacing. However, none of these studies has dealt with long-term follow-up results. OBJECTIVE: To review all side effects resulting from CO2 laser resurfacing with regard to both short- and long-term effects. METHOD: Retrospective analysis of 104 patients who have undergone CO2 laser resurfacing for either facial rhytides and/or scarring with follow-up periods of 4-23 months (average, 8.2 months). RESULTS: The incidence of side effects are generally very low for CO2 laser resurfacing, including scarring, postinflammatory hyperpigmentation, and infection. However, there is a significant and previously unreported risk of hypopigmentation in an area of the population who often seek improvement in the appearance. CONCLUSIONS: CO2 laser resurfacing of facial rhytides and acne scars can be a very safe procedure by an experienced laser operator. However, careful patient selection, thorough patient instruction, and proper aesthetic analysis of treatment sites must be followed to insure the most favorable outcomes with CO2 laser resurfacing

The development of high-peak power or scanned CO2 lasers that precisely remove layers of photodamaged skin has provided a novel method of skin rejuvenation. Clinical data suggest that laser resurfacing provides comparable or better results than conventional methods of chemical peeling and mechanical dermabrasion, with a lower risk-to-benefit ratio. Histologic studies of the effects of these lasers on tissue have been helpful in establishing guidelines for appropriate clinical use of these lasers and insights into the mechanisms whereby facial skin rejuvenation is achieved

Cutaneous laser resurfacing is already proving to be a highly effective tool for improving photodamaged or scarred skin. The clinical and histological effects of the new high-energy, pulsed carbon dioxide (CO2) systems compare favorably with other treatments such as dermabrasion and chemical peels. The tissue-tightening effect noted after laser treatment may account for the claims of superior clinical improvement and needs further investigation

BACKGROUND. New 'char-free' carbon dioxide lasers are capable of precise tissue vaporization with minimal residual thermal damage. These lasers operate either by producing high energy, rapid pulses or by scanning a highly focused continuous mode beam. OBJECTIVE. To determine the depth of ablation and the depth of residual thermal injury produced with one to three passes of the pulsed and scanned systems. METHODS. The distal ends of preauricular donor skin from 12 patients requiring full-thickness skin grafts following Mohs micrographic surgery were treated with zero to three passes of each of the lasers, and fixed for histopathological analysis. RESULTS. The three lasers tested produced vaporization of thin (20-50 microns) layers of tissue and narrow (20-150 microns) zones of thermal injury following one, two, or three passes on intact skin. CONCLUSION. The pulsed and scanned technologies are capable of producing 'char-free' tissue ablation with minimal residual thermal damage

BACKGROUND: The Q-switched ruby laser has been used successfully to treat a variety of benign pigmented lesions. In this study, congenital nevi (diameter, < or = 5 cm) in 18 prepubertal children were treated with the Q-switched ruby laser. OBSERVATIONS: Photographic evaluation revealed an average of 57% clearance of pigmentation in all treated nevi by the fourth treatment session and an average maximum clearance of 76% after approximately eight sessions. Greater than 90% clearance of pigment was attained in five patients. Partial repigmentation was seen in all patients who were followed up after discontinuation of therapy. Findings from histopathologic studies, obtained from one patient, revealed reduction of nevus cells in papillary dermis and upper reticular dermis that correlated with clinical lightening. There was no such reduction in the lower reticular dermis. side effects were limited to transient erythema and hypopigmentation. CONCLUSIONS: The Q-switched ruby laser effectively lightens and may clear pigmentation and eliminate superficial nevus cells from small and medium congenital nevi safely without scarring. However, these results are not permanent. The Q-switched ruby laser may be a viable alternative for providing cosmetic improvement for unresectable lesions, but it should not be considered definitive treatment. Additional studies are needed to address the long-term results of this therapy