INTRAOPERATIVE MONITORING AND POSTOPERATIVE IMAGING OF HEPATIC CRYOSURGERY

Because intraoperative sonography displays segmental anatomy, allows d iscovery of more lesions than previously suspected from preoperative i maging, surgical inspection, or palpation, and permits more certain di agnosis of problematic masses, it facilitates surgical decision-making when liver resection or cryoablation is anticipated. Intraoperative s onography provides a guidance modality to accurately place cryosurgery probes in liver masses. More precise treatment of metastatic and prim ary tumors of the liver is possible with cryoablation because intraope rative sonography provides a means of monitoring the growth of the enl arging freeze zone to insure adequate surgical margins. Postoperative detection of acute complications after cryosurgery is best done with c omputed tomography. Normally cryosurgery defects shrink with time and lose the peripheral contrast opacification seen after surgery. Gas col lections, seen as a result of tissue necrosis, must be discriminated f rom infection. Tumor recurrence can be detected well with computed tom ography or magnetic resonance imaging following hepatic cryosurgery. ( C) 1998 Wiley-Liss, Inc.