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 & b Ultrasonography may obscure the biliary system and CBD may be hidden behind multiple collaterals .The use of color Doppler ultrasound is able to detect large PCD and ECD collaterals and perforators which come to lie inside the CBD (video).
