Intraoperative use of subtraction angiography and an ultrasonic aspirator to improve identification and isolation of an intrahepatic portosystemic shunt in a dog.

Mesenteric portography, using a C-arm fluoroscope equipped with digital subtraction capability, was performed intraoperatively to locate a single, intrahepatic portocaval shunt. An ultrasonic aspirator was used to isolate the shunt, which was ligated completely. Typical portal venous arborization was seen on postligation intraoperative mesenteric portography. Subtraction angiography used intraoperatively and dissection with the ultrasonic aspirator improve the surgeon's ability to localize and isolate intrahepatic portocaval shunts and can reduce surgical time. Film development and patient repositioning and transport, before and after shunt ligation, are not necessary when mesenteric portography is performed intraoperatively, using a C-arm fluoroscope and digital subtraction. Dissection around intrahepatic portocaval shunts is facilitated by the ultrasonic aspirator, which selectively fractures and suctions tissue from around the shunt. Hemorrhage is decreased, because hepatic ductules and small blood vessels are left intact.