Experimental cryosurgery of the liver under magnetic resonance guidance.
The feasibility and the advantages of magnetic resonance (MR)-guided interstitial cryosurgery of the liver in an 0.5 Tesla open MR system have been evaluated. Cryosurgery was performed using an Erbocryo PS system with a nonmagnetic cryoprobe of 6 mm diameter. The probe was inserted into the liver parenchyma under real-time MR control. Using continuous MR imaging two freezing cycles of 12 min each were applied. After conventional and dynamic gadolinium-enhanced MR imaging, the animals were sacrificed after 30 min, 3 hr, 24 hr, 7 days, and 21 days. Each lesion was analyzed using light microscopy. A total of seven cryolesions were made in five animals without any complications from cryosurgery. During real-time imaging, cryolesions appeared as a hemispherical growing signal loss with a mean volume of 16.4 cm3. Macroscopic volumes of the lesions showed a good correlation with dynamic enhanced MR images during follow-up, whereas real-time images usually showed an underestimation of the lesion volumes. Cryosurgery of the liver in an open-configuration MR system is a feasible and safe method. MR imaging allows the guidance and the follow-up of cryolesions of the liver with good accuracy.
Klotz
H P
HP
Department of Surgery, University of Zurich Hospital, Switzerland. khp@chi.usz.ch
Flury
R
R
Schönenberger
A
A
Debatin
J F
JF
Uhlschmid
G
G
Largiadèr
F
F
D000818:Animals; D003452:Cryosurgery / Q000295:instrumentation*; D005240:Feasibility Studies; D005260:Female; D007091:Image Processing, Computer-Assisted / Q000295:instrumentation*; D008099:Liver / Q000473:pathology / Q000601:surgery*; D008279:Magnetic Resonance Imaging / Q000295:instrumentation*; D013552:Swine