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 Determine further evaluations needed

3. Reading Chapter 38 –Pages 483-493

4. Abdominal Radiography Generally being replaced with ultrasound –Ultrasound does not give a global picture Radiographs are a snapshot of disease –1/120 th 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) –Moderate image contrast –Some of shades of grey –More than bone less than thorax Moderate 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. Some incidential findings Lucency on the ventral aspect of L3-4 Cholesterol granulomas Spondylosis deformans

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

26. Cholesterol granuloma Generally in cats

27. Smooth bridging bone

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

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

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

31. Peritoneal fluid Soft tissue and fluid are similar opacity Therefore lose detail in the abdomen Ultrasound superior for peritoneal fluid Emaciation and fluid cause similar appearance, except for overall size of abdomen

32. Peritoneal fluid Multiple causes –Increased hydrostatic pressure –Decreased plasma colloid oncotic pressure –Capillary permeability Radiographs very insensitive for detecting Cannot tell fluid type from radiographs

33. Mild Severe

34. Lack of fat cause loss of detail

35. Is there peritoneal fluid?

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

37. Don’t forget that other view

38. 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

39. Medial iliac lymph nodes

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

41. Pneumoretropertioneum Retroperitoneum communicates with the mediastinum Therefore usually associated with: –Subcutaneous emphysema –Pneumomediastinum

42. Need large volume of gas Ruptured trachea Ruptured esophagus –Need aerophagia

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

44. Even in the cow!

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

46. Several places to look

47. What about large animal?

48. Foals and calves Can image abdomen –Usually standing –See fluid layers Can do barium enemas –Strictures or atresia ani

49. Ileus

50. Traumatic reticuloperitonitis

52. All about the belly in 1 hour! Good general overview Over the next 3 weeks will be focused Radiographs are a good overview Helpful even if large animal

53. Questions?