title: Residual thermal damage resulting from pulsed and scanned resurfacing lasers.
abstract: BACKGROUND
  Laser resurfacing with rapidly scanned or pulsed carbon dioxide (CO2) lasers has evolved rapidly in recent years. These lasers vaporize small amounts of tissue, while leaving minimal residual thermal damage.
  
  
  OBJECTIVE
  To compare the depth of residual thermal damage of two of the most commonly used CO2 laser systems. A rapidly scanned laser was compared to a short-pulse laser system.
  
  
  METHODS
  Laser treatment was performed on abdominoplasty specimens prior to removal in four subjects. One, two, or three passes of the two most commonly used energies were administered using each laser system.
  
  
  RESULTS
  The depth of thermal damage increased with a greater number of passes with each laser system. Higher energies resulted in greater residual thermal damage with each system after the first pass up to three passes, which was the maximum number of passes administered. Combining the second and third passes, residual thermal damage was remarkably similar when comparing the pulsed and scanned lasers.
  
  
  CONCLUSIONS
  The most commonly used energy settings of two lasers with very different modes of action resulted in remarkably similar depths of thermal damage, suggesting that the zone of thermal damage may correlate with clinical outcome. In addition, the zone of thermal damage enlarges as the number of passes increases from one to three.
authors.affiliation: Laser Surgery and Cosmetic Dermatology Center, Marlton, New Jersey, USA. Bernstee@seas.upenn.edu
authors.forename: E F
authors.initials: EF
authors.lastname: Bernstein
authors.forename: D B
authors.initials: DB
authors.lastname: Brown
authors.forename: J
authors.initials: J
authors.lastname: Kenkel
authors.forename: A J
authors.initials: AJ
authors.lastname: Burns
mesh_terms: D000328:Adult; D062109:Dermatologic Surgical Procedures; D005260:Female; D006358:Hot Temperature; D006801:Humans; D053685:Laser Therapy / Q000009:adverse effects* / Q000295:instrumentation; D007834:Lasers; D008875:Middle Aged; D012867:Skin / Q000293:injuries / Q000473:pathology*