Captivating Cases

Issue 16 - February 2015

We are excited to announce the addition of Beth Biscoe, DVM, MS, DACVR to the Animal Imaging team!

Dr. Biscoe provides comprehensive imaging services alongside Rita Echandi, DVM, DACVR and Dana Neelis, DVM, MS, DACVR on a full time basis.

Dr. Biscoe is a valuable addition to our team. She has experience in cross sectional imaging (MRI and CT) as well as ultrasound, fluoroscopy and nuclear medicine studies (portal scans, thyroid scans, I-131 and bone scans). We are certain you will appreciate the knowledge and skill that Dr. Biscoe brings to the Animal Imaging team.

Equipped for Success

Animal Imaging offers virtually every outpatient veterinary diagnostic imaging option available for small animal and equine, all in one location:

CT Scan
Fluoroscopy
MRI (3-Tesla)
Nuclear Medicine
Teleradiology
Ultrasound/Mobile Ultrasound

Transplenic Portal Scintigraphy

Signalment and History:

Lucas, an 8 month old, male intact miniature poodle, presented for Transplenic Portal Scintigraphy (Portal Scan) which was followed by an abdominal ultrasound. Lucas was obtained from the breeder at 3 weeks of age and had frequent seizures for several months until it was suspected that he had a shunt. His blood work showed low normal BUN and Albumin, elevated ALP and postprandial bile acids were very elevated at 351.3. At that time he was placed on medical management for a liver shunt. He had no additional seizures and was sent for evaluation of the suspected shunt.

Portal Scan Findings:

2.0 mCi of pertechnetate was injected into the splenic parenchyma with ultrasound guidance. Dynamic scintigraphy was performed. The bolus of the activity traveled from the spleen, through the splenic vein into the portal vein and into the shunting vessel. The pattern of uptake within this vessel angled caudally from the spleen, and dorsally entering the caudal vena cava caudal to the level of the left kidney. Blood then circulated into the systemic circulation and into the liver.

The trans-splenic scintigraphy is most supportive of a single macroscopic shunt vessel. The caudally directed flow is suggestive/supportive of portal hypertension.

Abdominal Ultrasound Findings:

There is turbulent flow within the caudal vena cava especially caudally, immediately cranial to the urinary bladder. Blood flow within the portal vein at the level of the portal hepatis is hepatofugal. There is an abnormal shunting vessel arising from the portal vein and angling into the region of the main splenic vein. However, this vein continues caudally, medial to the spleen and terminates in the caudal vena cava cranial to the level of the urinary bladder. There are abnormal plexi of vessels that have venous flow caudal to the right kidney, and left kidney. An abnormal plexus of vessels is also seen adjacent to the large shunting vessel arising from the portal vein at the level of the splenic vein. The liver is subjectively diffusely small. The parenchyma is mildly coarse. No nodules or masses are seen. There are reduced portal markings within the liver. The margins of the liver remain sharp. A mild volume of anechoic peritoneal effusion is seen from the abdomen most evident around the liver and spleen. The kidneys are subjectively mildly enlarged. The renal cortices are mildly hyperechoic. No definitive areas of mineralization or renal pelvic dilation are seen associated with the right kidney. The urinary bladder is moderately distended. Its contents is anechoic. No definitive calculi or crystals are seen within the urinary bladder. The bladder wall is normal.

Conclusion:

1. There is evidence of a large macroscopic shunt likely splenocaval in origin. In addition, there is evidence of portal hypertension and changes that support acquired portosystemic shunting.

2. The liver is small with reduce portal markings, supporting the diagnosis of portosystemic shunting.

3. Peritoneal effusion; differentials include hypoalbuminemia or ascites secondary to portal hypertension.

It is difficult to completely determine the exact origin of the patient's current findings. It is possible that the patient had a congenital macroscopic shunt and now has developed hepatic/portal fibrosis, portal hypertension, and acquired shunting. An additional differential includes severe microvascular dysplasia or non-cirrhotic portal hypertension with development of portal hypertension and acquired shunting.

In light of the presence of changes that support multiple acquired shunting and portal hypertension, surgical ligation of the larger portosystemic shunt is in the radiologist's opinion discouraged. If further information is needed regarding the abdomen, a CT (computed tomography) could be considered.