title: Histological alterations after irradiation of cartilage using Ho:YAG laser.
abstract: OBJECTIVE
  The authors carried out an experimental study to evaluate the histological alterations after irradiation of cartilage using Holmium:YAG (Ho:YAG) laser VersaPulse Select 60 watts and Infra Tome Delivery Systems 30 degrees Handpiece (spot size at fiber tip 0.4 mm; Coherent Medical, Palo Alto, CA).
  
  
  BACKGROUND
  Recently, some authors reported cases with articular cartilage damage following arthroscopic laser surgery in the knee joint for the treatment of articular cartilage or meniscal pathology.
  
  
  METHODS
  The cartilage specimens immersed in saline were exposed to Ho:YAG laser irradiation. The laser wavelength was 2.1 microm, and pulse duration was 250 microsec. Power settings were 0.2-1 joules per pulse and 10-15 Hz. Total laser energy used in these procedures was 1.5 K joules. During the procedures, the handpiece was used at an angle of 30 degrees and at a distance of 1 mm.
  
  
  RESULTS
  Electron microscopic evaluation demonstrated that the ultrastructure of the cartilage is preserved in both experiment and control groups.
  
  
  CONCLUSIONS
  When Ho:YAG laser is used in optimal dosage (optimal joule and Hertz) with optimal technique (keeping the handpiece at an appropriate angle and distance) and avoiding overtreatment, it does not cause cartilage damage.
authors.affiliation: Department of Orthopaedic Surgery, Gazi University Medical Faculty, Bugday Sokak 6/27, Kavaklidere 06700 Ankara, Turkey. atik@tr.net
authors.forename: O Sahap
authors.initials: OS
authors.lastname: Atik
authors.forename: Deniz
authors.initials: D
authors.lastname: Erdogan
authors.forename: Suna
authors.initials: S
authors.lastname: Omeroglu
authors.forename: Feza
authors.initials: F
authors.lastname: Korkusuz
authors.forename: M Murad
authors.initials: MM
authors.lastname: Uslu
authors.forename: Fatih
authors.initials: F
authors.lastname: Eksioglu
mesh_terms: D001182:Arthroscopy; D002358:Cartilage, Articular / Q000473:pathology / Q000528:radiation effects*; D019902:Chondrocytes / Q000473:pathology / Q000528:radiation effects; D003094:Collagen / Q000528:radiation effects / Q000648:ultrastructure; D006695:Holmium; D006801:Humans; D066298:In Vitro Techniques; D007719:Knee Joint; D053685:Laser Therapy / Q000295:instrumentation
chemical_list: D003094:Collagen; D006695:Holmium