Gadopentetate dimeglumine as an oral negative gastrointestinal contrast agent for MRCP.
BACKGROUND
We investigated the feasibility of using intravenous magnetic resonance (MR) contrast agent as a gastrointestinal oral negative contrast agent to null the bowel signal during MR cholangiopancreatography (MRCP).


METHODS
In the first part of the study, a phantom study was performed to select the optimal concentration of MR contrast agent to be used as an oral negative contrast agent in MRCP. In the second part of the study, 23 consecutive patients suffering from different pancreaticobiliary diseases were imaged with a single-shot fast spin-echo pulse sequence. The data acquisition was started without oral contrast agent and then repeated with oral contrast agent. From the MR images taken with and without oral contrast agent, the gallbladder, cystic duct, common bile duct, and pancreatic duct were assessed and graded by two radiologists.


RESULTS
The oral contrast agent was tolerated well by all patients. In all patients the high signal intensity from the intestinal fluid was completely suppressed. The depictions of the gallbladder and cystic duct were slightly and moderately improved, respectively, whereas the depictions of the common bile duct and pancreatic duct were markedly improved by the oral contrast agent administration.


CONCLUSIONS
Diluted intravenous MR contrast agent can be an effective and safe oral negative contrast agent in eliminating signal intensity of the gastrointestinal tract, thus improving the depiction of the biliary system in MRCP.
Department of Diagnostic Radiology, Tuen Mun Hospital, Tuen Mun, NT, Hong Kong, Republic of China.
J H
JH
Chan
E Y
EY
Tsui
M K
MK
Yuen
M L
ML
Szeto
S H
SH
Luk
K P
KP
Wong
N O
NO
Wong
D001660:Biliary Tract Diseases / Q000175:diagnosis; D003135:Common Bile Duct / Q000473:pathology; D003287:Contrast Media; D003549:Cystic Duct / Q000473:pathology; D005240:Feasibility Studies; D005260:Female; D019786:Gadolinium DTPA; D005704:Gallbladder / Q000473:pathology; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D008875:Middle Aged; D010182:Pancreatic Diseases / Q000175:diagnosis; D010183:Pancreatic Ducts / Q000473:pathology; D019047:Phantoms, Imaging
D003287:Contrast Media; D019786:Gadolinium DTPA