1. General Abdominal Radiography
Tony Pease, DVM, MS
Assistant Professor of Radiology
North Carolina State University

2. Objectives Acquisition of radiographs Abdominal radiographic anatomy
Radiographic patterns of abdominal disease
Determine normal compared to abnormal
How ultrasound is helpful

3. Reading
Chapters 38-40
Pages

4. Abdominal Radiography
Generally being replaced with ultrasound
Ultrasound does not give a global picture
Radiographs are a snapshot of disease
1/120th of a second picture
Ultrasound is real time

5. Abdominal Anatomy
A lot of organs in a small space
Rely on location

6. Acquiring radiographs
Relatively high kVp (70 kVp)
Moderate image contrast
Some of shades of grey
More than bone less than thorax
Moderate mAs (8-12 mAs)
Minimizes motion artifact
Maximizes contrast
Enemas and fasting are helpful

7. Positioning Include caudal thorax
Try to include greater trochanter of femur
Center beam just caudal to the last rib

10. Large patients May need two films per view Four films per study
Make sure to overlap images

12. Ventrodorsal Liver Spleen Left Kidney Right Kidney
Stomach and duodenum

14. Left lateral Esophagus Pylorus Duodenum Liver Spleen Left kidney
Right kidney
Urinary bladder

16. Right lateral Fundus Liver Spleen Left kidney Right kidney Urinary
bladder

17. Normal cat abdomen

18. Deep circumflex iliac artery
Sometimes confused for medial iliac lymph nodes or ureteral calculi

19. Positional radiographs
Remember gas rises
Can manipulate the animal

20. Can you see the gas?

22. Lateral horizontal beam

23. Horizontal beam Place the animal in left lateral
Puts the fundus of the stomach down
Smaller pylorus is high
Gas accumulates near the diaphragm

24. Now time for the radiographs!
Positioning – done
Exposure – done
Interpretation!
Takes radiologists years to become experts
You have 9 hours!

25. Quick word on abdominal masses
Hard to tell what organ is involved
Best guess based on location
What organs are displaced
May need ultrasound to be more specific

27. Some incidental findings
Lucency on the ventral aspect of L3-4
Cholesterol granulomas
Spondylosis deformans

28. Lack of ventral aspect of L4
It is where the diaphragm attaches

29. Cholesterol granuloma
Generally in cats

30. Smooth bridging bone

31. Spaces of the abdomen Retroperitoneal Peritoneal Dorsal to the colon
Contains kidneys, adrenal glands, lymph nodes
Continuous with mediastinum
Peritoneal
Surrounds visceral organs
Generally a potential space

32. Can compare spaces Retroperitoneal space Good detail Peritoneal space
Poor detail

33. Loss of serosal detail Poor radiographic technique
Fat content of a puppy or kitten
Peritoneal fluid (many types)
Carcinomatosis
Lack of fat
Peritonitis

34. Peritoneal fluid Soft tissue and fluid are similar opacity
Ultrasound superior for peritoneal fluid
Emaciation versus fluid
Similar appearance
Lack of fat to provide contrast
Difference is overall size of abdomen

35. Peritoneal fluid Radiographs very insensitive for detecting
Cannot tell fluid type
Radiographs or ultrasound!
Multiple causes
Increased hydrostatic pressure
Decreased plasma colloid oncotic pressure
Capillary permeability

36. Mild
Severe
Severe

37. Lack of fat cause loss of detail

38. Is there peritoneal fluid?

39. Retroperitoneal space
Only thing that is dorsal to the colon

40. Don’t forget that other view

41. Abdominal lymph nodes Many lymph nodes in abdomen
Generally not seen radiographically
Even if large
Medial iliac lymph nodes are the exception
Ultrasound more useful for lymph nodes

42. Medial iliac lymph nodes

43. Don’t forget about goats
Can help diagnose caseous lymphadenitis

44. Pneumoretroperitoneum
Retroperitoneum communicates with the mediastinum
Therefore usually associated with:
Subcutaneous emphysema
Pneumomediastinum

45. Need large volume of gas
Ruptured trachea
Ruptured esophagus
Need aerophagia

46. Pneumoretroperitoneum
Not generally clinically important
Just a sign of another disease

47. Even in the cow!

48. Pneumoperitoneum Can persist 10-14 days after surgery
Rupture of a hollow viscus
Gastrointestinal perforation
Surgical emergency!!
External puncture wound

49. Several places to look

50. What about large animal?

51. Foals, calves and pigs Can image abdomen Can do barium enemas
Usually standing
See fluid layers
Can do barium enemas
Strictures or atresia ani

52. Barium enema

53. Ileus

54. Traumatic reticuloperitonitis

55. Traumatic reticuloperitonitis

56. All about the belly in 1 hour!
Radiographs helpful even if large animal
Hard to tell where mass comes from
Radiographs are a good overview

57. Questions?