title: Clinical response of psoriasis to low-energy irradiance with the Nd:YAG laser at 1320 nm report of an observation in three cases.
abstract: BACKGROUND
  Psoriasis is a perplexing disease for which we have no definitive therapy. many types of lesions and clinical forms exist, from the small, localized indolent papule, to the persistent intractable plaque, to the disabling palmo-plantar involvement to the erythrodermic form. This wide variety of clinical manifestations has made it difficult to apply therapies such as lasers, which can reportedly produce an improvement. Although they have been shown to work, the carbon dioxide laser needs local injection for anesthesia along with healing by second intention, lasting for 3 to 6 weeks, while the flashlamp-pumped dye laser needs to be delivered in individual pulses of 5 to 10 mm in diameter each and repetition rates of only 1 to 2 pulses per second (1-2 Hz). These factors have made both lasers impractical for widespread use given the extensive skin involvement, which is often present.
  
  
  OBJECTIVE
  To report on the beneficial effects of this new apparatus in some psoriatic lesions as observed in 3 out of 3 individuals tested.
  
  
  METHODS
  Three patients who had lesions ranging from the small indolent papule to the persistent plaque, resistant to conventional treatment, to plantar involvement, underwent focal treatment with low-energy continuous emission of laser light below the threshold of pain for a total of 4 treatments in a span of 2 weeks.
  
  
  RESULTS
  A clinical response was observed in all 3 cases. Improvement was noticed at a 4-week follow-up visit and continued for 3 months. Early recurrence in 1 case was noted at the end of this period. Partial response in a case of plantar involvement was seen.
  
  
  CONCLUSIONS
  These findings are not only encouraging to undertake a study in a larger number of patients, with several different fluences and treatment frequencies, but are also intriguing regarding the possible mechanism or mechanisms of action.
authors.affiliation: University of California, San Diego, California, USA.
authors.forename: J
authors.initials: J
authors.lastname: Ruiz-Esparza
mesh_terms: D000368:Aged; D005260:Female; D006801:Humans; D053685:Laser Therapy; D008297:Male; D008875:Middle Aged; D011565:Psoriasis / Q000532:radiotherapy*; D016896:Treatment Outcome