An in vivo trial comparing the use of different types of 532 nm Nd:YAG lasers in the treatment of facial lentigines in Oriental patients.
BACKGROUND
Versapulse is a system that consists of four laser modalities and was developed with the aim of increasing cost-effectiveness. However, as these lasers share a common power supply, for the Q-switched (QS) Nd:YAG 532 nm laser a large spot diameter is necessary to lower the fluence to a suitable level. This can increase the risk of hyperpigmentation when used for the treatment of lentigines in dark-skinned patients.


OBJECTIVE
The aim of our study was to access the clinical efficacy and the complication rate of the Versapulse QS Nd:YAG 532 nm laser, the Versapulse long-pulsed Nd:YAG 532 nm laser (without the chill tip), and a conventional QS Nd:YAG 532 nm laser in the treatment of lentigines in Chinese patients.


METHODS
Thirty-four Chinese patients with lentigines were randomized to receive laser surgery, with one side of the face treated by one laser and the other side treated by a different system. Patients were monitored for 6 weeks to assess the degree of clearing, hyperpigmentation, hypopigmentation, and erythema. Assessments involved patients interviewed using a visual analog questionnaire and two blinded observers who evaluated the pre- and posttreatment clinical photographs.


RESULTS
The Versapulse QS Nd:YAG 532 nm laser was associated with a statistically higher risk of complications. The Versapulse long-pulsed Nd:YAG 532 nm laser was compatible with the conventional QS Nd:YAG 532 nm laser in terms of clinical efficacy and complication rates.


CONCLUSIONS
The Versapulse long-pulsed 532 nm laser is more effective and should be used instead of the Versapulse QS Nd:YAG 532 nm laser for the treatment of lentigines in dark-skinned patients.
Division of Dermatology, Department of Medicine, University of Hong Kong. henrychan@cuhk.edu.hk
H H
HH
Chan
W K
WK
Fung
S Y
SY
Ying
T
T
Kono
D000328:Adult; D044466:Asian People; D004311:Double-Blind Method; D004890:Erythema / Q000209:etiology; D005148:Facial Dermatoses / Q000473:pathology / Q000601:surgery*; D005260:Female; D006723:Hong Kong; D006801:Humans; D017495:Hyperpigmentation / Q000209:etiology; D017496:Hypopigmentation / Q000209:etiology; D053685:Laser Therapy / Q000009:adverse effects; D007834:Lasers; D007911:Lentigo / Q000473:pathology / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D009354:Neodymium; D016896:Treatment Outcome
D009354:Neodymium