EUS-guided portal vein carbon dioxide angiography: a pilot study in a porcine model.
BACKGROUND
Direct portal vein (PV) angiography can provide valuable clinical information but is not performed due to the high risk of complications.


OBJECTIVE
To assess the feasibility of EUS-guided PV angiography with a small-caliber FNA needle by using carbon dioxide (CO(2)) as a contrast agent in a porcine model.


METHODS
Acute experiments with 50-kg pigs under general anesthesia.


METHODS
Under linear array EUS guidance, the intrahepatic PV branch was punctured with a 25-gauge FNA needle. Portal venography was performed with iodinated contrast (Hypaque) and then with medical grade CO(2). After portography, the needle was removed from the PV and the animals were observed for 30 minutes, then euthanized for necropsy.


METHODS
Ability to visualize portal anatomy.


RESULTS
Six animal experiments were performed without complications. EUS-guided PV puncture with 25-gauge FNA needle was technically straightforward. Injection of ionic iodinated contrast through the 25-gauge FNA needle was arduous (mean [+/-SD] pressure 76.7 +/- 5.2 pounds per square inch [psi]), resulting in short (6.02 +/- 1.15 seconds) and poor opacification of the PV (visualization score 1.33 +/- 0.52). CO(2) injection through a 25-gauge needle was simple and easy (pressure 20.8 +/- 2.0 psi), producing prolonged (19.83 +/- 1.68 seconds) opacification of the entire portal system (visualization score 4.33 +/- 0.52). There was a statistically significant difference in all compared parameters (P < .0001) favoring injection of CO(2) over viscous iodinated contrast during portal angiography through a 25-gauge FNA needle. Postmortem examination revealed no active bleeding and no damage to the liver, other intra-abdominal organs, or blood vessels.


CONCLUSIONS
Acute animal experiments.


CONCLUSIONS
EUS-guided portal venography with CO(2) using a small (25 gauge) FNA needle appears feasible, technically simple, and safe.
Giday
Samuel A
SA
Department of Medicine, Division of Gastroenterology, Johns Hopkins Hospital, Baltimore, Maryland 21205, USA.
Ko
Chung-Wang
CW
Clarke
John O
JO
Shin
Eun Ji
EJ
Magno
Priscilla
P
Jagannath
Sanjay B
SB
Buscaglia
Jonathan M
JM
Kantsevoy
Sergey V
SV
D000818:Animals; D002245:Carbon Dioxide / Q000008:administration & dosage; D003287:Contrast Media / Q000008:administration & dosage*; D004195:Disease Models, Animal; D019160:Endosonography / Q000379:methods*; D005240:Feasibility Studies; D005260:Female; D006975:Hypertension, Portal / Q000000981:diagnostic imaging; D007275:Injections, Intravenous; D010690:Phlebography / Q000379:methods*; D010865:Pilot Projects; D011169:Portal Vein / Q000000981:diagnostic imaging*; D013552:Swine
D003287:Contrast Media; D002245:Carbon Dioxide