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Objectives/hypothesis The wound healing characteristics of incisions made with the short pulsed CO2 laser tuned to 9.55 microm versus the traditional 10.6 microm were investigated. Previous studies have shown that at 9.55 microm, collagen is targeted more selectively than at 10.6 microm, which results in decreased acute thermal injury patterns. This study investigates the difference in wound healing over time between lasers and compares laser incisions with cold knife techniques. Study design Randomized controlled trial using a porcine model. Methods Tissue from 10.6-microm and 9.55-microm incisions of 10 piglets was evaluated with histological analysis and tensiometry at 3, 7, 14, and 21 days postoperatively. A Bonferroni-Dunn corrected analysis of variance analysis at a 95% significance level was used to compare the effect of wavelength. Results The results demonstrate that although knife incisions are consistently stronger than laser incisions, the 9.55-microm CO2 laser incisions are no stronger than incisions made with the conventional 10.6-microm laser. Furthermore, histological analysis shows no difference in lateral thermal damage between lasers at 3, 7, 14, and 21 days postoperatively. The progression of collagen formation and inflammation does not differ over time. Conclusion This study of wound healing using a porcine model demonstrates that the 9.55-microm CO2 laser does not demonstrate an improvement in wound healing over the traditional 10.6-microm CO2 laser. These results may be secondary to the common explosive vaporization mechanism produced by both lasers in the infrared spectrum.

Objectives To investigate the effects of thermally conductive, optically transparent media placed on skin during treatment with the flashlamp excited dye laser (FEDL). The use of higher energy densities to treat persistent cutaneous vascular lesions may result in a decrease in the number of treatment sessions. However, increased fluences can cause complications of scarring, hyperpigmentation, infection, skin texture changes, or hypopigmentation. The thermally conductive media should assist in dissipating surface thermal energy and thereby protect the skin from the complications. Study Design This was a prospective laboratory study using an animal model. The results were verified in a prospective, pilot, human-use trial. Methods The threshold for acute skin damage and measurements of the thermal transients were made using a rabbit model. The threshold for purpura was noted with and without the use of a sapphire as a thermal conductor. The thermal transients were measured with small thermocouples placed subcutaneously. On a human subject, purpura intensities were photographed and measured using computer morphometrics after treatment with the FEDL and skin surface protection with air, glass, sapphire, and diamond as conductive media. Results With the interposition of the sapphire thermal conductor during the FEDL treatment, excessive temperature increases of the epidermis were prevented during the laser pulse compared with glass and controls. Both sapphire and diamond resulted in decreased purpuric intensities with the applications of equivalent fluences. Wound recovery time for the purpura was decreased by approximately half a day when any of the surface conductors were used. Conclusions The decreased transient temperature and decrease in purpura seen with the use of sapphire and diamond protecting the epidermis during treatment with the FEDL should result in fewer untoward effects during treatment of vascular lesions and facilitate their management.

Yellow wavelength lasers have revolutionized the treatment of benign vascular cutaneous lesions. The flashlamp excited dye laser provides optimal clearing of most benign lesions. Patients of all ages may be treated safely with minimal risk of inducing scarring or skin texture changes. Our technique for using the flashlamp excited dye laser is described.

Background and Objective A number of lasers are available for cutaneous periorbital surgery, yet not all eye shields are appropriate for all applications. We tested a variety of commercially available eye shields to assess their safety features. Study Design/Materials and Methods Six commercially available eye protectors were studied. A focused laser was incident upon the shield, and the intensity and exposure duration required for visible damage to the shield were measured. We then measured the temperature on the underside of the eye shield during exposure from the laser. Time-dependent temperature measurements were made with a type-T thermocouple fixed to the eye shield with silicon grease. Results Thermal response curves and rates of warming for each of the six eye shields were generated. Plastic shields showed significant thermal damage with most of the lasers tested. The metallic shields warmed more slowly and to a lesser degree. Conclusion Overall, the metallic eye shields had the most acceptable safety profile. Many of the plastic shields exhibited significant thermal damage, and therefore we discourage their use in periorbital laser surgery. © 1996 Wiley-Liss, Inc.