A tactile sensor for laparoscopic cholecystectomy

During laparoscopic surgery, surgeons observe the three-dimeasional abdominal cavity on a two-dimensional TV monitor, which is a limitation. Another limitation is that surgeons are unable to estimate the softness of organs or tissues during laparoscopic surgery as they are only allowed to use instruments which touch objects and direct palpation is not permitted during the procedure. The tactile sensor which we used displays the object softness immediately as a digital score, which can then be superimposed on a TV monitor as a graph. With the tactile sensor, we were able to ascertain the presence of a gallstone in the gallbladder or cholecystic duct during laparoscopic cholecystectomy and also able to discriminate between a stone and an air bubble during intraoperative cholangiography. We were convinced that the tactile sensor would be useful in laparoscopic surgery, which does not permit surgeons to palpate objects with human fingers.