MR MONITORING DURING CRYOTHERAPY IN THE LIVER - PREDICTABILITY OF HISTOLOGIC OUTCOME

For well-controlled application of cryotherapy to focal liver lesions, real-time monitoring is necessary to limit the final necrotic effect in the treated area. In this study, near real-time magnetic resonance (MR) monitoring images of normal rabbit liver were obtained during the freezing procedure. The MR-monitored, freezing-induced lesions were f ollowed with MR images for up to 3 weeks. Corresponding histologic sam ples were also obtained over the same time period. Our results indicat e that MR images obtained during the freezing procedure can adequately depict the area of final necrosis. Furthermore, histologic changes at each stage of lesion development correlated well with MR signal inten sities on follow-up images. With the development of an MR-compatible c ryogen probe, MR imaging may prove to be a robust method for monitorin g, controlling, and following up cryotherapy in the liver.