- Veterinary View Box
- Posts
- Spot the Pattern: Parenchymal vs. Portal Gas Changes Prognosis in Hepatic Emphysema
Spot the Pattern: Parenchymal vs. Portal Gas Changes Prognosis in Hepatic Emphysema
Veterinary Radiology & Ultrasound, 2019
Obi Veterinary Education
December 02, 2025
Sabrina Manfredi, Martina Fabbi, Mattia Bonazzi, Fabio Leonardi, Francesca Miduri, Ilaria Parroccini, Eleonora Daga, Giacomo Gnudi, Antonella Volta
Background
Hepatic emphysema in dogs and cats is a rare ultrasonographic finding that can involve gas in the liver parenchyma, portal veins, or biliary tract. Its clinical significance remains unclear, and differentiation between patterns may provide prognostic insights. This study aimed to categorize ultrasonographic patterns of hepatic gas and evaluate their correlation with clinical outcomes and underlying diseases.
Methods
This retrospective cross-sectional study evaluated 37 animals (33 dogs, 4 cats) with hepatic emphysema diagnosed by ultrasound between 2010 and 2018. Cases were classified as portal venous gas, parenchymal emphysema, or biliary emphysema based on imaging characteristics. Clinical, laboratory, imaging, and outcome data were collected and statistically analyzed for associations with outcome (favorable or poor).
Results
Twenty-three cases showed hepatic portal venous gas, 10 had parenchymal emphysema, and four had biliary emphysema. Portal venous gas was associated with more benign conditions (e.g., iatrogenic, gastrointestinal disease), and had a significantly lower mortality rate (21.7%) compared to parenchymal emphysema (90%). Increased liver enzymes and older age were also significantly associated with parenchymal emphysema. Portal gas was transient and resolved within 3 days in most cases. Parenchymal gas was often linked to severe liver pathology (neoplasia, suppurative hepatitis) and was persistent or recurrent in several cases. Biliary emphysema occurred post-surgery or with biliary infection and resolved in most cases.
Limitations
The retrospective nature, small sample size (especially for biliary emphysema), and lack of standardized diagnostics (e.g., CT or histopathology in all cases) limited interpretation. Prognostic conclusions may be influenced by variability in underlying diseases rather than gas patterns alone.
Conclusions
Ultrasonographic differentiation of hepatic gas patterns is clinically valuable. Portal venous gas typically indicates a more favorable prognosis, often resolving spontaneously, while parenchymal gas is associated with more severe liver disease and higher mortality. These findings can guide prognosis and help tailor diagnostic and therapeutic strategies in dogs and cats with hepatic emphysema.
Right lateral (A) and ventro-dorsal (B) radiographic views of the abdomen of a 12-year-old spayed female mixed breed dog with suppurative hepatitis (96 kVp, 10.00 mAs): gas lucencies are seen superimposed to the right and central hepatic silhouette (arrows) and in the pertioneal space (small arrows). Ultrasonographic image of the liver (C) in the same dog (longitudinal plane, 7.5 MHz linear array probe): hypoechoic lesion (arrows) and multiple hypoechoic foci with reverberation artifacts (arrowheads) within liver parenchyma indicating parenchymal emphysema. Pneumoperitoneum is seen on ultrasound (D) as thickening of the peritoneal stripe with reverberation artifacts (arrows)
How did we do? |
Disclaimer: The summary generated in this email was created by an AI large language model. Therefore errors may occur. Reading the article is the best way to understand the scholarly work. The figure presented here remains the property of the publisher or author and subject to the applicable copyright agreement. It is reproduced here as an educational work. If you have any questions or concerns about the work presented here, reply to this email.