Share Email Print
cover

Journal of Biomedical Optics

Laser-induced transepidermal elimination of dermal content by fractional photothermolysis
Author(s): Basil M. Hantash; Vikramaditya P. Bedi; Vasanthi Sudireddy; Steven K. Struck; G. Scott Herron; Kin Foong Chan
Format Member Price Non-Member Price
PDF $20.00 $25.00

Paper Abstract

The wound healing process in skin is studied in human subjects treated with fractional photothermolysis. In-vivo histological evaluation of vacuoles formed over microthermal zones (MTZs) and their content is undertaken. A 30-W, 1550-nm single-mode fiber laser system delivers an array of 60 µm or 140 µm 1/e2 incidence microbeam spot size at variable pulse energy and density. Treatments span from 6 to 20 mJ with skin excisions performed 1-day post-treatment. Staining with hematoxylin and eosin demonstrates an intact stratum corneum with vacuolar formation within the epidermis. The re-epithelialization process with repopulation of melanocytes and keratinocytes at the basal layer is apparent by 1-day post-treatment. The dermal-epidermal (DE) junction is weakened and separated just above zones of dermal coagulation. Complete loss of dermal cell viability is noted within the confines of the MTZs 1-day post-treatment, as assessed by lactate dehydrogenase. All cells falling outside the irradiation field remain viable. Content within the epidermal vacuoles stain positively with Gomori trichrome, suggesting a dermal origin. However, the positive staining could be due to loss of specificity after thermal alteration. Nevertheless, this dermal extrusion hypothesis is supported by very specific positive staining with an antihuman elastin antibody. Fractional photothermolysis creates microthermal lesions that allow transport and extrusion of dermal content through a compromised DE junction. Some dermal material is incorporated into the microepidermal necrotic debris and shuttled up the epidermis to eventually be exfoliated through the stratum corneum. This is the first report of a nonablative laser-induced transport mechanism by which dermal content can be predictably extruded biologically through the epidermis. Thus, treatment with the 1550-nm fiber laser may provide the first therapeutic option for clinical indications, including pigmentary disorders such as medically recalcitrant melasma, solar elastosis, as well as depositional diseases such as mucinosis and amyloidosis.

Paper Details

Date Published: 1 July 2006
PDF: 9 pages
J. Biomed. Opt. 11(4) 041115 doi: 10.1117/1.2241745
Published in: Journal of Biomedical Optics Volume 11, Issue 4
Show Author Affiliations
Basil M. Hantash, Reliant Technologies Inc. (United States)
Vikramaditya P. Bedi, Reliant Technologies, Inc. (United States)
Vasanthi Sudireddy, Reliant Technologies Inc. (United States)
Steven K. Struck, Struck Plastic Surgery (United States)
G. Scott Herron, Palo Alto Medical Foundation (United States)
Kin Foong Chan, Reliant Technologies Inc. (United States)


© SPIE. Terms of Use
Back to Top