title: Laser-induced thermotherapy for the treatment of liver metastasis. Correlation of gadolinium-DTPA-enhanced MRI with histomorphologic findings to determine criteria for follow-up monitoring.
abstract: OBJECTIVE
  To evaluate gadolinium (Gd)-diethylenetriamine-pentaacetic-acid (DTPA)-enhanced magnetic resonance imaging (MRI) for follow-up monitoring of laser-induced thermotherapy (LITT) and to determine a useful examination schedule.
  
  
  METHODS
  LITT of the liver was performed in 55 rabbits using a neodymium: yttrium-aluminum-garnet (Nd:YAG) laser (4-W power output, 840-s exposure time). Gd-DTPA MRI and histologic examinations were performed at different times (0-168 days).
  
  
  RESULTS
  Laser-induced lesions underwent regeneration and volume size reduction (69% after 168 days). The correlation coefficient (MR vs. macroscopic analysis) for the mean lesion diameter was r = 0.96. Histology of lesions comprised the four zones that correlated best with MRI findings. Coagulation necroses immediately after LITT was seen as an area of no enhancement on Gd-DTPA MRI. Circular enhancement was first seen 72-96 h after LITT, which was due to early mesenchymal proliferation.
  
  
  CONCLUSIONS
  Gd-DTPA MRI is a good monitoring procedure for LITT. MRI should be performed 24 and 96 h after LITT.
authors.affiliation: Department of General, Vascular, and Thoracic Surgery, University Hospital, Benjamin Franklin Freie Universität Berlin, Hindenburgdamm 30, 12200 Germany.
authors.forename: C
authors.initials: C
authors.lastname: Germer
authors.forename: C M
authors.initials: CM
authors.lastname: Isbert
authors.forename: D
authors.initials: D
authors.lastname: Albrecht
authors.forename: J P
authors.initials: JP
authors.lastname: Ritz
authors.forename: A
authors.initials: A
authors.lastname: Schilling
authors.forename: A
authors.initials: A
authors.lastname: Roggan
authors.forename: K J
authors.initials: KJ
authors.lastname: Wolf
authors.forename: G
authors.initials: G
authors.lastname: Müller
authors.forename: H
authors.initials: H
authors.lastname: Buhr
mesh_terms: D000818:Animals; D003287:Contrast Media; D005260:Female; D019786:Gadolinium DTPA; D006979:Hyperthermia, Induced / Q000379:methods*; D007089:Image Enhancement; D007834:Lasers; D008099:Liver / Q000473:pathology; D008113:Liver Neoplasms / Q000473:pathology / Q000628:therapy*; D008279:Magnetic Resonance Imaging; D008991:Monitoring, Physiologic; D011817:Rabbits
chemical_list: D003287:Contrast Media; D019786:Gadolinium DTPA