Image distortion in US-guided liver tumor puncture with curved linear array.

Our objective was to systematically examine the influence of probe geometry, puncture route, and composition of the abdominal wall on the deviation error with needle display. We made a simplified simulation model of the puncture needle passing to the liver tumor, using a microcomputer system, and visualized the degree of distortion of the puncture needle, changing the thickness and component of the abdominal wall as well as the radius of the probe, site, and angle of puncture. The puncture needle exhibited a displacement error of -10.9 to 3.8 mm (center hole) and -11.3 to 3.8 mm (side attachment). The shift was less accentuated when the radius of the probe was large. The displacement error was less accentuated in the center and accentuated in the left side of the field of view. It is recommended that liver puncture under US guidance be generally performed using a probe with a larger radius through the center hole with the most obtuse puncture angle possible, but when the tumor is localized in the hepatic dome, a more tightly curved probe should be used with an acute angle. We must consider a possible large error in display of the puncture needle during liver puncture and try to prevent hazardous complications.