title: The use of variable pulse width frequency doubled Nd:YAG 532 nm laser in the treatment of port-wine stain in Chinese patients.
abstract: BACKGROUND
  Variable pulse width frequency doubled Nd:YAG 532 nm laser has previously been shown to be effective in the treatment of vascular lesions in Caucasians. For dark-skinned patients, such as Asians, its role has not been determined.
  
  
  OBJECTIVE
  To assess the clinical efficacy and complication rate of the 532 nm Nd:YAG laser in the treatment of port-wine stain in Chinese patients.
  
  
  METHODS
  Chinese patients with port-wine stain who had undergone Nd:YAG laser treatment were called for questionnaire assessment of their degree of clearing and clinical examination for complications by two independent observers. For 22 patients with pre- and posttreatment photographs, the two independent observers further assessed the degree of clearing.
  
  
  RESULTS
  Assessment of the questionnaire indicated that 62.9% of the patients subjectively considered that they had more than 25% clearing, with 33.3% having more than 50% clearing. For those with pre- and posttreatment photographs, the objective degree of improvement was less impressive with 18.1% of patients having at least 25% improvement and only 13.6% having more than 50% improvement. Pigmentary and texture changes were seen in both groups (33% in group I and 11% in group II). The number of treatment sessions rather than previous use of pulsed dye laser therapy was an important risk factor for complications.
  
  
  CONCLUSIONS
  Nd:YAG laser is only partially effective for the treatment of port-wine stain in Chinese patients. Although most patients recorded some degree of subjective improvement, many did not improve by objective assessment. High fluence is necessary to achieve the desirable clinical response, and while contact cooling reduces the risk of epidermal damage, texture changes can still occur. Further study is necessary to compare its use with other similar devices, such as a pulsed dye laser with cryogen spray cooling.
authors.affiliation: Division of Dermatology, Department of Medicine, University of Hong Kong, Hong Kong.
authors.forename: H H
authors.initials: HH
authors.lastname: Chan
authors.forename: E
authors.initials: E
authors.lastname: Chan
authors.forename: T
authors.initials: T
authors.lastname: Kono
authors.forename: S Y
authors.initials: SY
authors.lastname: Ying
authors.forename: H
authors.initials: H
authors.lastname: Wai-Sun
mesh_terms: D000328:Adult; D044466:Asian People; D002681:China / Q000208:ethnology; D005260:Female; D006723:Hong Kong; D006801:Humans; D053685:Laser Therapy / Q000009:adverse effects / Q000379:methods*; D008297:Male; D019339:Port-Wine Stain / Q000601:surgery*; D012307:Risk Factors; D011795:Surveys and Questionnaires; D016896:Treatment Outcome