Official websites use .gov
A
.gov website belongs to an official
government organization in the United States.
Secure .gov websites use HTTPS
A lock (
) or https:// means you've safely
connected to the .gov website. Share sensitive
information only on official, secure websites.
a The serial dilators used to create the endoscopic portal. b The assembly of the serial dilators. c The setup of the working channel, which was mounted rigidly on the surgical table. d The endoscope and attached camera. Note the 20-degree offset of the light source
