One Duct, Two Oriﬁces, No Names! The Anatomy
of the Biliary Cystic Duct
RADHIKA MERH ,* MICHAEL SAUNDERS,
Department of General Surgery, Conquest Hospital, St. Leonards-on-Sea, East Sussex,
TN37 7RD, United Kingdom
The biliary cystic duct (CD) connects the gallbladder to the extra-hepatic bile
duct, and the point at which it does this delineates the division between the
common hepatic duct and the common bile duct. Its clinical relevance in dis-
ease, and importance during interventions relating to the gallbladder mean
that its normal and variant anatomy has been described extensively in litera-
ture. However, an aspect not yet fully described includes naming of its two ori-
ﬁces on either end. This is highly relevant for surgical, endoscopic, and
percutaneous procedures. We describe these as encountered in normal CD and
biliary tree anatomy. We believe this is crucial for interventions relating to the
gallbladder and the biliary tree, including prevention of iatrogenic injury. Clin.
Anat. 31:422–423, 2018.
2018 Wiley Periodicals, Inc.
Key words: gallbladder; cystic duct; biliary tree; anatomy
The biliary cystic duct (CD) connects the gallbladder
to the extra-hepatic bile duct, and the point at which it
does this delineates the division between the common
hepatic duct and the common bile duct (CBD) (Turner
and Fulcher, 2001; Standring, 2016). Its clinical rele-
vance in pathology, and importance during interven-
tions relating to the gallbladder means that its normal
and variant anatomy has been described extensively in
the literature (Turner and Fulcher, 2001).
Although the CD’s two oriﬁces on either end have
been previously discussed (Dasgupta and Stringer,
2005), perhaps due to a lack of clear functional contri-
bution, they have not yet been named. This is highly
relevant for radiology and surgical, endoscopic, and
percutaneous procedures. We describe these as
encountered in normal CD and biliary tree anatomy.
There is “oriﬁce A,” an oriﬁce of the CD that opens
into the gallbladder (Fig. 1). This oriﬁce may be
directly encountered in a sub-total cholecystectomy
when part of the gallbladder is excised in a challeng-
ing case of cholecystectomy. Visualization of this ori-
ﬁce is key in orientating the surgeon during such
In normal anatomy, “oriﬁce B,” the other oriﬁce of
the CD opens into the extra-hepatic bile duct (Fig. 1).
This is the oriﬁce that the endoscopist recognizes ﬁrst
when they inject contrast material into the biliary duc-
tal system during endoscopic retrograde cholangio-
pancreatography; contrast is seen passing through
the CBD from the duodenum in a retrograde fashion
to enter the CD through this oriﬁce.
In previously published literature, “oriﬁce B” has
been described as a junction and an entry point but
these are misleading as both oriﬁces can be viewed as
entry and exit points (Turner and Fulcher, 2001). Bile
ﬂows from the liver into the gallbladder, and from the
gallbladder into the CBD to enter the duodenum. Using
words such as proximal and distal oriﬁces can be poten-
tially confusing as what is proximal to the endoscopist
focusing on the biliary tree could be distal in the techni-
cal sense to the surgeon operating on the gallbladder.
*Correspondence to: Radhika Merh, Department of General
Surgery, Conquest Hospital, The Ridge, St. Leonards-on-Sea,
East Sussex TN37 7RD, UK. E-mail: email@example.com
Conﬂict of interest: There are no conﬂicts of interest to declare.
Received 14 September 2017; Revised 12 December 2017;
Accepted 18 December 2017
Published online 25 January 2018 in Wiley Online Library
(wileyonlinelibrary.com). DOI: 10.1002/ca.23039
2018 Wiley Periodicals, Inc.
Clinical Anatomy 31:422–423 (2018)