title: Use of a new ICG-dye-enhanced diode laser for percutaneous laser disc decompression.
abstract: OBJECTIVE
  The lasers used today for Percutaneous Laser Disc Decompression (PLDD) can not selectively ablate the nucleus pulposus (NP). We hypothesized that if indocyanine green dye were injected into the NP, 805 nm diode laser irradiation would result in selective and safe removal of NP tissue without damaging nearby tissues.
  
  
  METHODS
  Twelve beagle dogs were used for three experiments, i.e., determination of attenuation coefficients of NP and AF, determination of weight of NP before and after laser irradiation, and histopathological study.
  
  
  RESULTS
  The attenuation coefficient at 805 nm of NP which had been homogenized in the presence of ICG was 2521.3/cm. Upon application of the diode laser at a power of 1, 3, or 5 W (the intensity of laser irradiation: 0.353, 1.061, or 1.768 x 10(3) W/cm(2)) to NPs into which ICG had been injected, the weight of the NPs decreased by a mean 20, 45, and 65%, respectively. Macroscopic and microscopic examination of the discs after PLDD showed that only the NP where the tissues were stained by ICG were removed.
  
  
  CONCLUSIONS
  These results indicated that the combined use of ICG and diode laser irradiation effectively and selectively ablates the NP with low laser power.
authors.affiliation: Department of Orthopaedic Surgery, National Defense Medical College, Tokorozawa, Saitama, Japan. ma-sato@md-phd.com
authors.forename: M
authors.initials: M
authors.lastname: Sato
authors.forename: M
authors.initials: M
authors.lastname: Ishihara
authors.forename: T
authors.initials: T
authors.lastname: Arai
authors.forename: T
authors.initials: T
authors.lastname: Asazuma
authors.forename: T
authors.initials: T
authors.lastname: Kikuchi
authors.forename: T
authors.initials: T
authors.lastname: Hayashi
authors.forename: T
authors.initials: T
authors.lastname: Yamada
authors.forename: M
authors.initials: M
authors.lastname: Kikuchi
authors.forename: K
authors.initials: K
authors.lastname: Fujikawa
mesh_terms: D000818:Animals; D004396:Coloring Agents; D019299:Decompression, Surgical / Q000295:instrumentation* / Q000379:methods*; D004285:Dogs; D007208:Indocyanine Green; D007403:Intervertebral Disc / Q000473:pathology / Q000528:radiation effects / Q000601:surgery*; D053685:Laser Therapy / Q000295:instrumentation* / Q000379:methods*; D008159:Lumbar Vertebrae / Q000473:pathology / Q000528:radiation effects / Q000601:surgery*
chemical_list: D004396:Coloring Agents; D007208:Indocyanine Green