Abstract
A 14 month-old Yorkshire terrier was presented with hyperammonemia and neurological disorder. Helical computed tomographic portography showed a single extrahepatic portosystemic shunt between left colic vein and caudal vena cava. Mesenteric portography after laparotomy revealed the other shunt inconsistently visualized around left gastric vein. The both shunts were safely ligated and hyperammonemia was disappeared. This case report shows a rare case of extrahepatic CPSS in a dog and the importance of mesenteric portography especially after shunt ligation, not for missing other shunts.
