Histologic evaluation of a millisecond Nd:YAG laser for hair removal.
BACKGROUND
Hirsutism and hypertrichosis are common problems. Laser-assisted hair removal has recently become a popular method to remove unwanted hair. However, histologic changes of the hair follicle after exposure to laser continue to require further investigation.


OBJECTIVE
To determine the thermal effect of a millisecond Nd:YAG hair removal laser.


METHODS
Six patients with black hair were treated with 50 msec pulsed Nd:YAG laser at fluences 30, 50 or 100 J/cm(2). Histologic examinations were performed on each laser-treated site at 24-72 hours after laser exposure.


RESULTS
Fluence-dependent selective thermal injury to follicles was seen. The average depth of acute laser injury at fluences 30, 50 and 100 J/cm(2) were 1.06, 0.85 and 1.11 millimeters, respectively.


CONCLUSIONS
Long-pulsed millisecond Nd:YAG lasers produce selective thermal damage of hair follicles. Varied laser fluences used in this study did not statistically alter the degree of thermal injury.
Skin Laser & Surgery Specialists of New York & New Jersey, NJ Medical School, Newark, New Jersey, USA.
D J
DJ
Goldberg
S
S
Silapunt
D000328:Adult; D001707:Biopsy, Needle; D005260:Female; D005500:Follow-Up Studies; D006204:Hair Removal / Q000379:methods*; D006801:Humans; D053685:Laser Therapy; D007834:Lasers / Q000009:adverse effects; D008297:Male; D009354:Neodymium; D010784:Photomicrography; D012016:Reference Values; D018570:Risk Assessment; D012867:Skin / Q000473:pathology* / Q000528:radiation effects*; D013997:Time Factors
D009354:Neodymium