Use of magnetic resonance angiography for diagnosis of portosystemic shunts in dogs

A prospective study was conducted to determine the sensitivity and specific ity of diagnosis of portosystemic shunts (PSS) and the accuracy of anatomic ally locating single congenital PSS in dogs using magnetic resonance angiog raphy (MRA). MRA was performed on 10 normal dogs and 23 dogs with PSS. Sens itivity and specificity of MRA to diagnose any shunt among all dogs were 80 % and 100%, respectively. Among dogs identified with PSS, sensitivity and s pecificity of MRA for diagnosis of multiple extrahepatic shunts were 63% an d 97%, respectively, and for diagnosis of single congenital shunts were 79% and 100%, respectively. Using MRA, radiologists correctly identified shunt s as extrahepatic or intrahepatic in 83% of patients and correctly identifi ed the origin and insertion of the shunts in 57% and 97% of patients, respe ctively. Use of MRA is specific for diagnosis of PSS and is a sensitive ind icator of anatomic location of single congenital portosystemic shunts.