1. Er:YAG laser skin resurfacing using repetitive long‐pulse exposure and cryogen spray cooling: I. Histological study*
- Author
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Majaron, Boris, Kelly, Kristen M, Park, Hyle B, Verkruysse, Wim, and Nelson, J Stuart
- Subjects
Biomedical and Clinical Sciences ,Clinical Sciences ,Skin ,Animals ,Burns ,Combined Modality Therapy ,Cryotherapy ,Dermatologic Surgical Procedures ,Disease Models ,Animal ,Drug Delivery Systems ,Female ,Hot Temperature ,Injury Severity Score ,Laser Therapy ,Lasers ,Neodymium ,Rats ,Rats ,Sprague-Dawley ,Skin Temperature ,collagen denaturation ,dynamic cooling ,repetitive laser exposure ,skin remodeling ,thermal damage ,Dermatology & Venereal Diseases ,Clinical sciences ,Dentistry - Abstract
Background and objectiveTo evaluate histologically the characteristics of repetitive Er:YAG laser exposure of skin in combination with cryogen spray cooling (CSC), and its potential as a method of laser skin resurfacing.Study design/materials and methodsRat skin was irradiated in vivo with sequences of 10 Er:YAG laser pulses (repetition rate 20 Hz, pulse duration 150 or 550 micros, single-pulse fluence 1.3-5.2 J/cm(2)). In some examples, CSC was applied to reduce epidermal injury. Histologic evaluation was performed 1 hour, 1 day, 5 days, and 4 weeks post-irradiation.ResultsA sequence of ten 550-micros pulses with fluences around 2 J/cm(2) resulted in acute dermal collagen coagulation to a depth of approximately 250 microm, without complete epidermal ablation. CSC improved epidermal preservation, but also diminished the coagulation depth. Four weeks after irradiation, neo-collagen formation was observed to depths in excess of 100 microm.ConclusionsDermal collagen coagulation and neo-collagen formation to depths similar to those observed after CO(2) laser resurfacing can be achieved without complete ablation of the epidermis by rapidly stacking long Er:YAG laser pulses. Application of CSC does not offer significant epidermal protection for a given dermal coagulation depth.
- Published
- 2001