Thermal fixation of swine liver tissue after magnetic resonance-guided high-intensity focused ultrasound ablation

Frédéric Courivaud; Airazat M Kazaryan; Alice Lund; Vivian C Orszagh; Aud Svindland; Irina Pavlik Marangos; Per Steinar Halvorsen; Peter Jebsen; Erik Fosse; Per Kristian Hol; Bjørn Edwin

doi:10.1016/j.ultrasmedbio.2014.02.007

Thermal fixation of swine liver tissue after magnetic resonance-guided high-intensity focused ultrasound ablation

Ultrasound Med Biol. 2014 Jul;40(7):1564-77. doi: 10.1016/j.ultrasmedbio.2014.02.007. Epub 2014 Apr 24.

Authors

Affiliations

¹ The Intervention Centre, Oslo University Hospital, Oslo, Norway. Electronic address: Frederic.courivaud@rr-research.no.
² The Intervention Centre, Oslo University Hospital, Oslo, Norway; Institute of Clinical Medicine, Medical Faculty, University of Oslo, Oslo, Norway.
³ Department of Pathology, Oslo University Hospital, University of Oslo, Oslo, Norway; Department of Pathology, Vestre Viken Hospital Trust, Drammen, Norway.
⁴ Department of Pathology, Akershus University Hospital, Lørenskog, Norway.
⁵ Department of Pathology, Oslo University Hospital, University of Oslo, Oslo, Norway; Institute of Clinical Medicine, Medical Faculty, University of Oslo, Oslo, Norway.
⁶ The Intervention Centre, Oslo University Hospital, Oslo, Norway.
⁷ Department of Pathology, Oslo University Hospital, University of Oslo, Oslo, Norway.
⁸ 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.

PMID: 24768489
DOI: 10.1016/j.ultrasmedbio.2014.02.007

Abstract

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.

Keywords: Hyperthermia; Liver ablation; Magnetic resonance-guided high-intensity focused ultrasound; Swine model; Thermal fixation.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Animals
Hepatectomy / methods*
High-Energy Shock Waves
High-Intensity Focused Ultrasound Ablation / methods*
Liver / cytology*
Liver / surgery*
Magnetic Resonance Imaging, Interventional / methods*
Male
Radiation Dosage
Swine