In vivo laser-induced interstitial thermotherapy of pig liver with a temperature-controlled diode laser and MRI correlation.
OBJECTIVE
To evaluate the efficacy of a new temperature-controlled Diode laser to generate in vivo tissue coagulations with laser-induced interstitial thermotherapy (LITT) in pig liver and MRI-correlation of these necroses.


METHODS
Each of four animal subjects received eight treatments at four different constant temperatures (70, 80, 90, and 100 degrees C) and at two out of three different intervals (3, 6, 9 minutes), resulting in a total of 32 lesions. After sacrificing, the liver was examined in an open MRI (0.35T). Tissue necrosis was measured macroscopically and compared with the size measured by MRI.


RESULTS
The size of the necrosis was energy dependent with the largest extent at 100 degrees C at 9 minutes (2.1 cm). The correlation between macroscopic lesion size and MRI findings was significant (P > 0.036). Histological workup excluded carbonization in every case.


CONCLUSIONS
LITT carried out with the Diode laser provides reproducible necroses of pig liver in vivo. MR-imaging results compared favorably with those obtained by pathologic specimens.
Wohlgemuth
W A
WA
Department of Radiology, Klinikum Augsburg, Stenglinstrasse 2, D-86156 Augsburg, Germany. w.wohlgemuth@online.de
Wamser
G
G
Reiss
T
T
Wagner
T
T
Bohndorf
K
K
D000818:Animals; D001918:Brachytherapy / Q000295:instrumentation*; D004195:Disease Models, Animal; D005240:Feasibility Studies; D006979:Hyperthermia, Induced / Q000295:instrumentation*; D017075:Laser Coagulation / Q000295:instrumentation*; D053685:Laser Therapy; D008099:Liver / Q000473:pathology* / Q000528:radiation effects*; D008113:Liver Neoplasms / Q000473:pathology* / Q000532:radiotherapy*; D008279:Magnetic Resonance Imaging; D009336:Necrosis; D013552:Swine