Yet again, thin film banding of portosystemic shunts is getting a bad wrap (pun intended) for failing to attenuate portosystemic shunts in dogs. Two recent publications in Veterinary Surgery by Dr. Or et al (here and here) described the use of CT angiography to better define portoazygous shunts and the transdiaphragmatic approach required to attenuate them at their insertion within the thoracic cavity. In their study, 9 dogs had transdiaphragmatic attenuation of their portoazygous shunts using either "Marlborough cigarette" wrapping or an ameroid.
The authors contended that the dogs that had their shunts banded using cigarette packaging failed to attenuate due 'potential differences in the ability of the thoracic cavity to mount a fibrous reaction.' This reasoning is fair, but flawed for the following reasons: