At VCA Animal Referral and Emergency Center we use a CT scan with contrast (angiogram) for identification of liver shunts. CT scan is more sensitive and specific than ultrasound for diagnosis. This test is typically performed under sedation.
Abdominal ultrasound is considered the least invasive. However, it only has approximately 70% sensitivity (ability to diagnose a portosystemic shunt when present). Abdominal CT scan and cranial mesenteric arteriograms require sedation and are costly, but they provide the anatomy of the shunting vessel. Surgical correction of liver shunts is recommended if possible. Medical management is done via controlling clinical signs. This is best attained by using a combination of diet, lactulose, and sometimes the use of antibiotics. Treatment is tailored to each individual patient and monitored with follow up exams and blood testing.