Equine Colic: Ultrasonographic and Radiographic Diagnosis

1. Equine Colic:Ultrasonographic and Radiographic Diagnosis Mattie McMaster and Friends

2. Introduction In the wild, there is no healthcare. • Colic • ABDOMINAL PAIN • Most commonly associated with gastrointestinal abnormalities • Outcome: • Resolve spontaneously • Medical treatment • Surgical treatment COLIC

3. Badness!!!

4. Diagnostic Tools • Patient history and signalment • Physical exam • CBC, biochemistry and blood-gas • Naso-gastric intubation • Rectal palpation • Abdominocentesis • ULTRASONOGRAPHY • RADIOGRAPHY • Exploratory surgery

5. Ultrasonography and Radiology

6. Indications This is a good day to save lives… • Obtain a more specific diagnosis • Decide if surgical intervention is necessary • Estimate prognosis

7. Ultrasonography: Equipment + + +/- =

8. Preparation

9. Transducer Game-face • Low frequency transducer • Sector transducer • Curvilinear transducer • Machine position

10. Scan Regions

11. Normal No surgery?

12. Equine Abdomen

13. Spleen Oh hey. Left

14. Stomach Left

15. Kidneys Left Right

16. Duodenum Right

17. Small Intestine Left

18. Large Intestine Left Right

19. That’s what she said. Cecum Right

20. Scan Patterns Mmmmm, scan patterns. • Three patterns • Mucous • Fluid • Gas • Evaluate • Wall thickness • Layering • Uniformity • Luminal Contents • Peristalsis

21. Abnormal Through concentration, I can raise and lower my cholesterol at will.

22. Medical Colic Brilliant diagnosis. • Enteritis/ duodenitis • Right dorsal colitis • Verminous arteritis • Gastric distension • Gastric ulceration • Gastric SCC • Intestinal neoplasia • Abdominal abscess • Peritonitis

23. Enteritis/ Duodenitis • Fluid distension of intestinal tract with increased peristalsis • Developing enteritis • Wall thickened, edematous and more hypoechoic • Shreds of intestinal mucosa in lumen • Marked fluid distension of stomach Figure 1

24. Duodenitis Figure 2

25. Right Dorsal Colitis • Non-steroidal anti-inflammatory drug toxicity • Thickened right dorsal colon • Ventral to liver in right 10th-14th intercostal spaces Figure 3

26. Gastric Distension • Stomach is enlarged and filled with fluid • Hyperechoic ventral layer representing ingesta • Hyperechoic dorsal layer casting dirty shadows consistent with gas Figure 4

27. Intestinal Neoplasia • Not routinely visualized on transcutaneous ultrasound • Lymphosarcoma • Within intestinal wall • Diffuse irregular filling • Marked enlargement of mesenteric lymph nodes Figure 5

28. Abdominal Abscess • Found: • Ventral abdomen • Root of mesentery • Cecum • Large colon • Fluid-filled or solid • Movement of adjacent bowel should be examined: • Adhesions between adjacent intestine and abscess Figure 6

29. Peritonitis • Ventral abdomen • 6.0 to 10.0 MHz transducer • Evaluate fluid: • Relative quantity • Character • Evaluate: • Abdomen, gastrointestinal and abdominal viscera should be scanned for source of peritonitis • Abdominal abscess or devitalized bowel

30. Surgical Colic Let’s have some fun…. • Herniation/ displacement • Nephrosplenic ligament entrapment • Sand colic/ enterolithiasis • Intussusceptions • Large colon torsion • Strangulating small intestinal and small colon lesions • Small intestine masses • Impaction

31. Herniation/ Displacement • Abnormal position of gastrointestinal viscera difficult to diagnose • Exceptions: • Scrotum • Thoracic cavity • Umbilical hernia Figure 9

32. Nephrosplenic Ligament Entrapment • Dorsal spleen and left kidney not visible in left caudal abdomen • Visualize ingesta or gas-filled large bowel • Spleen ventrally displaced • Bright hyperechoic reflection dorsal to the spleen from the bowel Figure 10

33. Sand Colic/ Enterolithiasis • RADIOGRAPHS • Not often used in adult horses • Exceptions: • Sand Colic • Enteroliths Figure 11

34. Enterolithiasis Figure 12

35. Sand Colic • Small, pinpoint granular hyperechoic echoes • Multiple acoustic shadows • Ventral most portion of the affected intestine • Limits peristaltic movement

36. Enterolithiasis • Enteroliths, bezoars, fecaliths, Hasselhoffs • Affected bowel in ventral abdomen • Hyperechoic mass casting strong acoustic shadow within intestine lumen • Distension of intestine proximal Oh hey.. Figure 13: Badness.

37. Intussusceptions • Ileum and large bowel • Right side of abdomen • “Target sign” • Fibrin tags between segments of intestine Figure 14

38. Intussusceptions Figure 15

39. Large Colon Torsion • Increased wall thickness of the large colon • Increased wall thickness is diffusely hypoechoic Badness! Figure 16

40. Strangulating Small Intestinal Lesions • Distended, fluid-filled small intestine proximal to strangulated portion of small intestine • Strangulated small intestine • Thickened, edematous, hypoechoic walls • Little or no peristaltic activity • Ventral portion of abdomen Figure 17

41. Small Intestinal Masses • Within intestinal wall • Thickened wall • Anechoic to echogenic • Carcinoids, leiomyomas, granulomas, hematomas, and fibrosis • Stricture secondary to chronic colic • Intestinal obstruction • Within lumen • Hemorrhage appears as echogenic clots or echoic swirling fluid Figure 18

42. Impaction • Round to oval distended viscus • Lack visible sacculations • Wall normal to increased thickness • Large acoustic shadows from impacted ingesta • Distension of intestine proximal • Little to no motility Figure 19

43. Conclusion • Early referral and surgical intervention is key to successful outcome • Ultrasonography and Radiology: • Obtain a more specific diagnosis • Decide if surgical intervention is necessary • Estimate prognosis

44. QUESTIONS?