Faculty Bibliography

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

The Q-switched ruby and the Q-switched neodymium YAG lasers are both widely used in the treatment of amateur and professional tattoos. Comparative evaluation of these two laser systems has not previously been performed; thus, the advantages of each laser have not been delineated. Forty-eight amateur and professional tattoos were treated with both the Q-switched ruby and Q-switched Nd:YAG lasers. The tattoos were divided in half and one side of the tattoo was treated with each laser. After one treatment, the patients returned for evaluation to assess the degree of lightening achieved by each laser. The Q-switched ruby laser was found to be superior in lightening black dye in both professional and amateur tattoos. A significant advantage was noted for the ruby laser in the removal of green tattoo pigment. The differences with the Q-switched ruby laser and the 1064 nm option of the Q-switched YAG laser were not clinically significant in the lightening or removal of other colors. The 532 nm option of the Q-switched YAG laser was superior to the Q-switched ruby and the 1064 nm option of the YAG laser in the removal of red tattoo colors in professional tattoos. Hypopigmentation was found more commonly with the Q-switched ruby laser, while textural change was noted more commonly with the Q-switched Nd:YAG laser. One of the patients treated with the Nd:YAG laser at 1064 nm showed a hypertrophic scar

OBJECTIVE: To determine the safety and efficacy of the flashlamp-pumped pulsed dye laser for the treatment of uncomplicated and recalcitrant warts. DESIGN: Observational study. PATIENTS: A total of 142 patients with 703 recalcitrant and 25 previously untreated warts consecutively referred to two tertiary care laser centers from July 1993 through January 1994. INTERVENTION: Photocoagulation with the flashlamp-pumped pulsed dye laser. MAIN OUTCOME MEASURES: Complete resolution of treated warts after a follow-up ranging from 3 to 9 months. RESULTS: The overall response rates were 99% for body, limb, and anogenital warts; 95% for hand warts; 84% for plantar warts; and 83% for periungual warts. Side effects were limited and infrequent. CONCLUSION: Pulsed dye laser therapy is a highly effective and safe method used to selectively destroy warts without damaging the surrounding skin

BACKGROUND. Recent advances in carbon dioxide (CO2) laser technology have resulted in the development of lasers that can precisely remove thin layers of skin with minimal thermal damage to the surrounding tissue. These lasers rely on rapid pulsing or scanning of the laser beam. The effects of these lasers are predictable and reproducible, making them ideal for skin resurfacing. Clinical results have been promising, however, to date, no published series exist. OBJECTIVE. To evaluate the effectiveness and side effect profile of laser resurfacing utilizing a CO2 laser with a scanning device, and make recommendations for patient selection and treatment protocol. METHODS. Patients with perioral, periorbital, and glabellar rhytides were treated with a CO2 laser with a scanning device. Utilizing chart review and photographic evaluation, patients treated between November 1994 and April 1995 were retrospectively evaluated for effectiveness of therapy, healing time, and complication rates. RESULTS. A total of 47 patients were evaluated. Photographic evaluation or chart review revealed good to excellent cosmetic results in all anatomic areas studied. All patients experienced posttreatment erythema lasting 1-6 months. Other minor complications were limited to contact dermatitis to topical preparations, transient postinflammatory hyperpigmentation, and milia formation. One patient experienced a primary herpes simplex virus infection during reepithelialization and required intravenous therapy. Minor focal atrophy was seen in one patient. No hypertrophic scarring or permanent pigmentation changes were seen. CONCLUSIONS. A CO2 laser system with a scanning beam can effectively and safely improve or remove glabellar, perioral, and periorbital rhytides

BACKGROUND. Approximately 50-75% lightening of port-wine stains is achieved within two to three treatments with pulsed dye laser therapy, but the incidence of complete clearing is variable. OBJECTIVE. This study was designed to: 1) assess the ability of continued repetitive pulsed dye laser treatments to further lighten persistent port-wine stains; 2) evaluate the factors contributing to the resistance of port-wine stains to laser therapy; and 3) determine the relative risk of adverse effects following repetitive treatments to the same area. METHODS. A retrospective photographic analysis was performed of 69 patients that failed to achieve greater than 75% lesional lightening within nine treatment sessions. The percentage improvement was assessed by comparing the degree of lightening at the last treatment to that of the midway point of treatment. RESULTS. Significant improvement in port-wine stain lightening, from the midway to last treatment, was seen in patients who had 10-25 repetitive treatments. CONCLUSION. Repetitive treatments with the pulsed dye laser can lead to improvement in the overall lightening of persistent port-wine stains without an increased risk of adverse effects