Totally transumbilical endoscopic cholecystectomy without visible abdominal scar using improved instruments. 
The major barrier to transumbilical endoscopic surgery is external interference between the instrument handles around the umbilicus.  We describe technique of totally transumbilical endoscopic cholecystectomy using improved instruments.  New trocars (5 and 3 mm in diameter, respectively) without proximal seal system on the sleeves were designed for this procedure.  The maximum diameters of the trocars were reduced to 8 and 5 mm, respectively.  The instruments used in this study were 5 cm longer than commercially available instruments.  Ten cases of totally transumbilical cholecystectomy were performed successfully.  All the gallbladders were removed successfully without severe bleeding during dissection, except one case of gallbladder wall perforation by cautery.  Mean operating time was 62 +/- 25 min (range 45-110 min).  All patients were satisfied with abdominal cosmetic results, discharged 48 h after the operation, and returned to work within seven postoperative days.  External interference between trocars and instruments can be partially avoided by using the improved instruments.  Totally transumbilical endoscopic cholecystectomy becomes feasible with this technique.