Table 1.

Comparisons of three routes for natural orifice transluminal endoscopic surgery procedure

Items	Trans-umbilical route	Trans-anal route	Trans-vaginal route
Access position	Visually inspected at para-umbilical region	Verified by finger pressing	Located by surrounding anatomic landmarks
Time to complete a trans-visceral incision	About 1 min
Time to reach peritoneum	About 2 min
Liver exposure	Antero-lateral segments could be easily detected, while posterosuperior segments were hard to be explored
Working platform	Unstable	Relatively stable
Time to hydro-dissection	Abandoned 1 h later	2 h	2 h and 40 min
Size of resected liver segment	No resected specimen was obtained due to failure in trans-umbilical hepatic resection	50 mm × 25 mm × 5 mm	45 mm × 30 mm × 7 mm
Bile leak	Not found
Blood loss	100 mL	200 mL	250 mL
Injury to surrounding organs	Not occurred