SONOGRAPHICALLY GUIDED LAPAROSCOPY AND MEDIASTINOSCOPY USING MINIATURE CATHETER-BASED TRANSDUCERS

Miniature ultrasound transducers (12.5 MHz) housed in 9 Fr catheters w ere passed through a laparoscope or mediastinoscope to image a variety of normal and abnormal structures within the peritoneal cavity and me diastinum in 20 patients. These transducers made it possible to visual ize the gallbladder and bile ducts and evaluate for the presence of st ones, to detect masses and provide guidance for their aspiration or bi opsy, and to image the internal structures of the ovary and fallopian tube. In addition, these miniature transducers were used to locate suc h normal vital structures as blood vessels, thereby allowing the surge on to decide on the best approach for dissection during mediastinoscop y. During conventional surgery, the surgeon or gynecologist can palpat e an area of abnormality not directly visualized. However, during lapa roscopy and mediastinoscopy direct palpation is not possible. Therefor e, it is important to find another method to determine what structures lie beneath the visualized surface. These miniature ultrasound transd ucers appear to offer a means for making such determinations.