A new extraction bag to facilitate stone extraction in laparoscopic cholecystectomy: in vitro experiments.

In order to avoid extension of the parietal wound when the stone load is too large to be simply extracted in laparoscopic cholecystectomy, we developed a new extraction bag. The new extraction bag has a characteristic shape to arrange the stones or fragments in a linear order. To evaluate the efficacy of the new bag we conducted in vitro stone extraction experiments and compared the new bag technique with conventional stone removal techniques. Mean experiment time to extract 60 small stones in a conventional technique group was 710 seconds, whereas it was 316 seconds with the new bag technique (p < 0.001). With this technique larger stones are also extracted without extending the parietal incision once they are fragmented in the bag. The results of our experiments suggest the new extraction bag as a simple and safe technique in minimally invasive stone extraction in laparoscopic cholecystectomy.