title: Temperature Distributions of the Lumbar Intervertebral Disc during Laser Annuloplasty : A Cadaveric Study.
abstract: OBJECTIVE
  Low back pain, caused intervertebral disc degeneration has been treated by thermal annuloplasty procedure, which is a non-surgical treatement. The theoretical backgrounds of the annuloplasty are thermal destruct of nociceptor and denaturization of collagen fiber to induce contraction, to shrink annulus and thus enhancing stability. This study is about temperature and its distribution during thermal annuloplasty using 1414 nm Nd : YAG laser.
  
  
  METHODS
  Thermal annuloplasty was performed on fresh human cadaveric lumbar spine with 20 intact intervertebral discs in a 37℃ circulating water bath using newly developed 1414 nm Nd : YAG laser. Five thermocouples were attached to different locations on the disc, and at the same time, temperature during annuloplasty was measured and analyzed.
  
  
  RESULTS
  Thermal probe's temperature was higher in locations closer to laser fiber tip and on lateral locations, rather than the in depth locations. In accordance with the laser fiber tip and the depth, temperatures above 45.0℃ was measured in 3.0 mm depth which trigger nociceptive ablation in 16 levels (80%), in accordance with the laser fiber end tip and laterality, every measurement had above 45.0℃, and also was measured temperature over 60.0℃, which can trigger collagen denaturation at 16 levels (80%).
  
  
  CONCLUSIONS
  When thermal annuloplasty is needed in a selective lesion, annuloplasty using a 1414 nm Nd : YAG laser can be one of the treatment options.
authors.affiliation: Department of Neurosurgery, St. Vincent's Hospital, The Catholic University of Korea, Suwon, Korea.
authors.forename: Min Hyung
authors.initials: MH
authors.lastname: Lee
authors.affiliation: Department of Neurosurgery, St. Vincent's Hospital, The Catholic University of Korea, Suwon, Korea.
authors.forename: Il Sup
authors.initials: IS
authors.lastname: Kim
authors.affiliation: Department of Neurosurgery, St. Vincent's Hospital, The Catholic University of Korea, Suwon, Korea.
authors.forename: Jae Taek
authors.initials: JT
authors.lastname: Hong
authors.affiliation: Department of Neurosurgery, St. Vincent's Hospital, The Catholic University of Korea, Suwon, Korea.
authors.forename: Jae Hoon
authors.initials: JH
authors.lastname: Sung
authors.affiliation: Department of Neurosurgery, St. Vincent's Hospital, The Catholic University of Korea, Suwon, Korea.
authors.forename: Sang Won
authors.initials: SW
authors.lastname: Lee
authors.affiliation: Department of Neurosurgery, Memorial Hermann Hospital, University of Texas Health Science Center at Houston, Houston, TX, USA.
authors.forename: Daniel H
authors.initials: DH
authors.lastname: Kim
keywords: Intervertebral disc degeneration; Low back pain; Nd : YAG laser; Temperature