Equine Colic: Ultrasonographic and Radiographic Diagnosis Mattie McMaster and Friends Introduction In the wild, there is no healthcare. Colic ABDOMINAL PAIN Most commonly associated with gastrointestinal abnormalities Outcome: Resolve spontaneously Medical treatment Surgical treatment Diagnostic Tools Patient history and signalment Physical exam CBC, biochemistry and blood-gas Naso-gastric intubation Rectal palpation Abdominocentesis ULTRASONOGRAPHY RADIOGRAPHY Exploratory surgery Indications This is a good day to save lives… Obtain a more specific diagnosis Decide if surgical intervention is necessary Estimate prognosis Ultrasonography: Equipment + + +/- = Preparation Transducer Game-face Low frequency transducer Sector transducer Curvilinear transducer Machine position Scan Regions Normal No surgery? Equine Abdomen Spleen Oh hey. Left Stomach Left Kidneys Left Right Duodenum Right Small Intestine Left Large Intestine Left Right That’s what she said. Cecum Right Scan Patterns Three patterns Mucous Fluid Gas Evaluate Wall thickness Layering Uniformity Luminal Contents Peristalsis Mmmmm, scan patterns. Abnormal Through concentration, I can raise and lower my cholesterol at will. Medical Colic Brilliant diagnosis. Enteritis/ duodenitis Right dorsal colitis Verminous arteritis Gastric distension Gastric ulceration Gastric SCC Intestinal neoplasia Abdominal abscess Peritonitis Enteritis/ Duodenitis Fluid distension of intestinal tract with increased peristalsis Developing enteritis Wall thickened, edematous and more hypoechoic Shreds of intestinal mucosa in lumen Figure 1 Marked fluid distension of stomach Duodenitis Figure 2 Right Dorsal Colitis Non-steroidal antiinflammatory drug toxicity Thickened right dorsal colon Ventral to liver in right 10th-14th intercostal spaces Figure 3 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 Intestinal Neoplasia Not routinely visualized on transcutaneous ultrasound Lymphosarcoma Within intestinal wall Diffuse irregular filling Marked enlargement of mesenteric lymph nodes Figure 5 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 Peritonitis Ventral abdomen Evaluate fluid: 6.0 to 10.0 MHz transducer Relative quantity Character Evaluate: Abdomen, gastrointestinal and abdominal viscera should be scanned for source of peritonitis Abdominal abscess or devitalized bowel Surgical Colic Herniation/ displacement Nephrosplenic ligament entrapment Sand colic/ enterolithiasis Intussusceptions Large colon torsion Strangulating small intestinal and small colon lesions Small intestine masses Impaction Let’s have some fun…. Herniation/ Displacement Abnormal position of gastrointestinal viscera difficult to diagnose Exceptions: Scrotum Thoracic cavity Umbilical hernia Figure 9 Nephrosplenic Ligament Entrapment Dorsal spleen and left kidney not visible in left caudal abdomen Visualize ingesta or gasfilled large bowel Spleen ventrally displaced Bright hyperechoic reflection dorsal to the spleen from the bowel Figure 10 Sand Colic/ Enterolithiasis RADIOGRAPHS Not often used in adult horses Exceptions: Sand Colic Enteroliths Figure 11 Enterolithiasis Figure 12 Sand Colic Small, pinpoint granular hyperechoic echoes Multiple acoustic shadows Ventral most portion of the affected intestine Limits peristaltic movement Enterolithiasis Enteroliths, bezoars, fecaliths, Hasselhoffs Oh hey.. Affected bowel in ventral abdomen Hyperechoic mass casting strong acoustic shadow within intestine lumen Distension of intestine Figure 13: Badness. proximal Intussusceptions Ileum and large bowel Right side of abdomen “Target sign” Fibrin tags between segments of intestine Figure 14 Intussusceptions Figure 15 Large Colon Torsion Increased wall thickness of the large colon Increased wall thickness is diffusely hypoechoic Badness! Figure 16 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 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 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 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 QUESTIONS?