Thermal fixation of swine liver tissue after magnetic resonance-guided high-intensity focused ultrasound ablation.
The aim of this study was to investigate experimental conditions for efficient and controlled in vivo liver tissue ablation by magnetic resonance (MR)-guided high-intensity focused ultrasound (HIFU) in a swine model, with the ultimate goal of improving clinical treatment outcome. Histological changes were examined both acutely (four animals) and 1 wk after treatment (five animals). Effects of acoustic power and multiple sonication cycles were investigated. There was good correlation between target size and observed ablation size by thermal dose calculation, post-procedural MR imaging and histopathology, when temperature at the focal point was kept below 90°C. Structural histopathology investigations revealed tissue thermal fixation in ablated regions. In the presence of cavitation, mechanical tissue destruction occurred, resulting in an ablation larger than the target. Complete extra-corporeal MR-guided HIFU ablation in the liver is feasible using high acoustic power. Nearby large vessels were preserved, which makes MR-guided HIFU promising for the ablation of liver tumors adjacent to large veins.
The Intervention Centre, Oslo University Hospital, Oslo, Norway. Electronic address: Frederic.courivaud@rr-research.no.
Frédéric
F
Courivaud
The Intervention Centre, Oslo University Hospital, Oslo, Norway; Institute of Clinical Medicine, Medical Faculty, University of Oslo, Oslo, Norway.
Airazat M
AM
Kazaryan
Department of Pathology, Oslo University Hospital, University of Oslo, Oslo, Norway; Department of Pathology, Vestre Viken Hospital Trust, Drammen, Norway.
Alice
A
Lund
Department of Pathology, Akershus University Hospital, Lørenskog, Norway.
Vivian C
VC
Orszagh
Department of Pathology, Oslo University Hospital, University of Oslo, Oslo, Norway; Institute of Clinical Medicine, Medical Faculty, University of Oslo, Oslo, Norway.
Aud
A
Svindland
The Intervention Centre, Oslo University Hospital, Oslo, Norway; Institute of Clinical Medicine, Medical Faculty, University of Oslo, Oslo, Norway.
Irina Pavlik
IP
Marangos
The Intervention Centre, Oslo University Hospital, Oslo, Norway.
Per Steinar
PS
Halvorsen
Department of Pathology, Oslo University Hospital, University of Oslo, Oslo, Norway.
Peter
P
Jebsen
The Intervention Centre, Oslo University Hospital, Oslo, Norway; Institute of Clinical Medicine, Medical Faculty, University of Oslo, Oslo, Norway.
Erik
E
Fosse
The Intervention Centre, Oslo University Hospital, Oslo, Norway.
Per Kristian
PK
Hol
The Intervention Centre, Oslo University Hospital, Oslo, Norway; Institute of Clinical Medicine, Medical Faculty, University of Oslo, Oslo, Norway; Department of Gastrointestinal and Hepatobiliary Surgery, Oslo University Hospital, Oslo, Norway.
Bjørn
B
Edwin
D000818:Animals; D006498:Hepatectomy / Q000379:methods*; D019220:High-Energy Shock Waves; D057086:High-Intensity Focused Ultrasound Ablation / Q000379:methods*; D008099:Liver / Q000166:cytology* / Q000601:surgery*; D053783:Magnetic Resonance Imaging, Interventional / Q000379:methods*; D008297:Male; D011829:Radiation Dosage; D013552:Swine
Hyperthermia; Liver ablation; Magnetic resonance-guided high-intensity focused ultrasound; Swine model; Thermal fixation