Intraoperative magnetic resonance imaging ablation of hepatic tumors

BACKGROUND: The use of hepatic ablation of tumors for both primary and secondary cancers has continued to increase at a significant rate. The most significant increase in the use of hepatic ablation has come from image-guided techniques with computed axial tomography and ultrasound. Limitations to targeting hepatic lesions by these techniques remain morbid obesity, abnormal hepatic parenchyma, and inability to visualize lesions without the use of intravenous contrast. In contrast, magnetic resonance imaging (MRI) has continued to provide a high contrast of soft tissue-to-lesion conspicuity without the need for intravenous dye. The recent development of open-configuration magnetic resonance scanners--which have allowed improved patient access, near real-time imaging, and more available MRI-compatible equipment--has opened up an entire new area of image-guided surgical and interventional procedures. METHODS: The principles and indications for all types of image-guided hepatic ablations are described. RESULTS: The success and limitations of image-guided ablation techniques. CONCLUSIONS: Image-guided hepatic ablation represents a useful technique in managing hepatic tumors. Intraoperative MRI represents a new technique with initial success that has been limited to European centers. Further evaluation in United States centers has demonstrated intraoperative MRI to be useful for certain hepatic tumors that cannot be adequately visualized by ultrasound or computed axial tomography. A multidisciplinary approach involving a surgical oncologist and interventional radiologist remains integral to the short- and long-term success of image-guided ablation.