Clinical experience with sector scan and linear array ultrasound probes in laparoscopic surgery

Laparoscopic ultrasonography combines the advantages of diagnostic laparoscopy and intraoperative contact ultrasonography. The early prototypes were based on the linear array intraoperative ultrasound transducer, which provided the hepatobiliary surgeon with detailed information on the hepatic and pancreatic tumour in addition to its relationship with the associated vasculature. The laparoscopic linear array probes provide similar information in patients submitted to diagnostic laparoscopy and provide the surgeon with rectilinear images that are easy to interpret. Laparoscopic sector scanning probes are now available and have the advantage of requiring only a small area of contact to produce a pie-shaped scan of the area of interest. Such images may be more difficult to orientate, but end viewing probes enable rapid changes in image direction when rotated and are probably the probe of choice in the detection of choledocholithiasis. At the present time, the laparoscopic ultrasonographer may have need of both probes to enable adequate evaluation of intraabdominal pathology. Technological advances will almost certainly provide more versatile ultrasound systems that will confirm the place of laparoscopic ultrasonography as a valuable investigative tool during laparoscopic procedures.