7091 Easy and sure new technique to mark the resecting area of colon on laparoscopic surgery.

Purpose With spread of laparoscopic surgery for colon, more reliable way to find the lesion from the serosa side during the surgery became more important.We developed new technique to mark the lesion. Marking was usually done by injecting Indian ink with needle through the fiberscope from mucosal side of colon in Japan. But injection not a few failed to limit the ink within the wall of colon. We tried to apply the EMR technique to the marking. Methods The principle is first to inject 2-3ml of saline into submucosal layer with needle device, to make submucosal upheaval of about 1cm and continuously to change saline to ink and inject it. Then we could limit the ink firmly. We modified these methods to find the best way in respects of ink concentration, amount, location and period until the surgery. Baseline conditions were 11% Indian ink, 0.5ml in amount, every 2 points at both oral and anal side at a distance of 5cm from tumor margin and 2days before the surgery. Alternatives were 5%, 0.2ml, 3cm from the margin, respectively. The better conditions were examined. Subjects were 30cases in total, 5cases each in baseline and alternative of concentration, amount and distance. Injection was performed at 2days before surgery in 18cases, 3days before in 4cases and 7days before in 8cases. Results In 30cases, there were no leak of ink into peritoneal cavity, but 20%(4/20) on ordinary methods in the past. In our new technique, 5% in concentration was easier to inject smoothly. 0.2ml in amount was better on the points of size of staining on surgery. There was no difference in local spread of ink among periods from marking until the surgery. Conclusions The principle and details of our new technique for marking on laparoscopic surgery is easy and sure method.