[The role of intraoperative ultrasonography].

Intraoperative ultrasonography (US) is able to visualize the inside of the viscera in real time, and is also both noninvasive and simple to perform without influence of the bone or alimentary canal gas disturbing the propagation of the ultrasound. US has recently been widely used for neurosurgery or abdominal surgery, 1) to check the position and size of the tumor, which can not be directly visualized, and to evaluate the relationship between the tumor and blood vessel or tissue, 2) to search for lesions not detected before surgery, 3) to search for residual tumor, 4) to carry out ultrasound-guided biopsy or puncture. For effective intraoperative US, thorough knowledge of the US instrument and the local anatomy is necessary. The medical technologists who routinely perform US are qualified to assist with intraoperative US.