Radiology3- Liver and Spleen

  1. What are anatomical characteristics of the liver? (4)
    • largest solid organ in the abdomen
    • located between the diaphragm and the stomach--> enlargement causes displacement of stomach
    • should be nearly all within the costal arches
    • caudal ventral border is the left lateral liver lobe, which has a sharp triangular-shaped margin
  2. What are radiographic characteristics of the gall bladder? (2)
    • not identifiable when normal
    • border effaces with surrounding liver; need a change in opacity to see on rads
  3. How can you assess the size of the liver?
    • gastric axis is USUALLY parallel to the ribs; in deep chested dogs gastric acid is cranial; in shallow bodied dogs, gastric acid is caudal
    • young animals will appear to have large livers
  4. Describe the orientation of the liver in cats.
    • majority of liver is right-side on VD image
    • abundant falciform fat may cause dorsal displacement of liver
  5. What are radiographic characteristics of a normal liver? (4)
    • soft tissue opaque
    • sharp margins
    • within costal arches
    • gastric axis parallel to ribs and perpendicular to spine
  6. What radiographic changes suggest generalized enlargement of the liver? (3)
    • blunting of caudoventral liver margin
    • extension beyond the costal arches
    • caudal +/- medial displacement of the gastric axis
  7. Why might older dogs have normal livers that APPEAR larger on radiographs?
    stretching/ elongation of triangular ligaments attached to the diaphragm
  8. What are causes of generalized hepatomegaly? (5)
    • congestion (right heart failure)
    • inflammation
    • neoplasia
    • vacuolar hepatopathy
    • endocrine hepatopathy
  9. What are common radiographic findings with focal hepatomegaly (mass)? (1)
    asymmetrical shift of gastric axis (pedunculated masses may not cause a gastric axis shift)
  10. What are differentials for focal hepatomegaly? (5)
    • neoplasia
    • abscess
    • cyst
    • hyperplastic nodule
    • granuloma
  11. How does microhepatia appear radiographically?
    cranial displacement of gastric axis
  12. What are causes of microhepatia? (2)
    • congenital portosystemic shunt
    • chronic┬áliver disease and cirrhosis
  13. What might cause a decrease in hepatic opacity (becomes more radiolucent)? (3)
    • abscess
    • biliary gas
    • portal vein gas
  14. What might cause an increase in liver opacity (becomes more radiopaque)? (4)
    • post-contrast
    • cholelithiasis
    • mineral within the intrahepatic bile ducts
    • mineralized mass (neoplasia, granuloma, hematoma)
  15. On ultrasound, the liver is _______ to spleen.
  16. How thick should the gallbladder wall be on ultrasound of dogs and cats?
    • dogs: 2-3mm thick
    • cats: <1mm thick
  17. What are causes of hepatic hyperechogenicity on ultrasound? (4)
    • vacuolar hepatopathy
    • infiltrative neoplasia
    • chronic active inflammation
    • cirrhosis (often with irregular nodules)
  18. What are differentials for hepatic nodules? (7)
    • nodular hyperplasia
    • metastatic neoplasia
    • granuloma
    • vacuolar change
    • hematoma
    • abscess
    • cysts
  19. How does a biliary mucocele appear on ultrasound?
    like cross-section of a kiwi
  20. What are anatomic characteristics of the spleen? (3)
    • only anchor is to the gastric fundusby the gastrosplenic ligament, otherwise location and size are variable
    • tail may extend along left body wall or across the body
    • splenic head is triangular (dorsally)
  21. How might generalized splenomegaly appear on radiographs? (2)
    • rounded or blunted margins of the spleen
    • dorsal +/- caudal displacement of jejunum
  22. What are causes for generalized splenomegaly? (5)
    • congestion
    • neoplastic infiltration
    • splenitis
    • extra-medullary hematopoiesis
    • lymphoid hyperplasia
  23. On ultrasound, the spleen is _________ to the liver and has __________.
    hyperechoic; fine echotexture
  24. How does splenic torsion appear on ultrasound?
    hypoechoic and "lacy" with no doppler signal
  25. What are differentials for splenic nodules? (7)
    • lymphoid hyperplasia
    • extramedullary hematopoiesis
    • hematoma
    • neoplasia
    • granuloma
    • myelolipoma
    • infarcts
Card Set
Radiology3- Liver and Spleen
vetmed radiology3