Intraoperative US of the liver: techniques and clinical applications.

Intraoperative ultrasonography (US) of the liver provides the operating surgeon with useful real-time diagnostic and staging information that may result in an alteration in the planned surgical approach. Current applications for intraoperative US of the liver include tumor staging, metastatic survey, guidance for metastasectomy and various tumor ablation procedures, documentation of vessel patency, evaluation of intrahepatic biliary disease, and guidance for whole-organ or split-liver transplantation. To obtain the most useful information with intraoperative US, the sonographer should use a dedicated transducer and a scanning method appropriate for the purpose of the examination. In addition, the radiologist must be familiar with the relevant intraoperative and vascular anatomy and the spectrum of normal and abnormal findings and should be alert to the pitfalls that frequently occur in the interpretation of intraoperative US images of the liver.