GI, Free air, Lymph Nodes

1. GI, Free air, Lymph Nodes Dr. LeeAnn Pack Dipl. AVCR

2. Esophagus - Anatomy • UES & LES • Dorsal to the larynx • Left of the trachea • Dorsal to the heart • Enters abdomen via esophageal hiatus

3. Esophagus - Function • 3 Stages • oropharyngeal • esophageal • gastroesophageal • Goal = to transport ingesta

4. The Normal Esophagus - Survey Radiographs • Normally not seen • May be seen with: • Gas and or metal/mineral in lumen • In patients with pneumomediastinum • Aerophagia - commonly see esophagus

5. The Esophagram! • Indications • Technique • What’s normal? • Common radiographic esophageal abnormalities

6. Esophagram - Indications • Radiographic &/or C/S of esophageal disease • Regurgitation • Dysphagia • Anorexia / Weight loss • Recurrent secondary pneumonia • To ID location, size and shape of the esophagus

7. Esophagram - Technique • Lateral recumbency • Administer contrast media • Barium paste (mucosal detail) • Barium liquid ( luminal / motility evaluation) • Organic Iodine (if suspect a perforation) • Be Careful with this --> pulmonary edema • Make exposure when patient swallows

8. Contrast Agents

9. Esophagram – What’s Normal? • Peristalsis • Dogs - longitudinal folds (skeletal) • Cats - longitudinal folds – cranial (2/3) (skeletal) and oblique folds caudal (1/3) (smooth) = herringbone pattern

10. Radiographic Abnormalities • Pooling of contrast / Dilation • Hypo-motility • Adherence of the contrast to the mucosa • Constriction / Narrowed lumen • Filling defects

11. Megaesophagus • Focal or diffuse esophageal dilation with hypo-motility • Congenital / Acquired • Numerous causes • Aspiration pneumonia - secondary

12. Generalized Megaesophagus

13. Generalized Megaesophagus

15. Vascular Ring Anomaly • Congenital malformation of great vessels • PRAA - young dogs • Radiographic appearance • esophageal dilation cranial to heart base • ventral displacement of trachea • pooling of contrast cranial to constriction • normal or hypo-motile caudal esophagus

16. Survey Films

17. With Barium

18. PRAA – Segmental Megaesophagus

19. More Examples of PRAA

20. Esophageal Foreign Bodies • Soft Tissue, Mineral or Metal density • Common sites: • thoracic inlet, heart base, LES • Radiographic appearance • focal distention of the esophagus • pneumomediastinum, pleural effusion, mediastinal fluid, strictures

21. Fish Hook with String

22. Esophageal Neoplasia • Primary - ACA, LMS, SCC, FS, OSA • Metastatic - more common • Spirocerca lupi • May see obstruction, stricture, mass

23. Esophageal Hernias • Hiatal • most common - congenital or traumatic • Paraesophageal • Gastroesophageal intussusception • All appear as increase ST opacity - caudal mediastinum/esophagus • esophagram to confirm

24. Hiatal Hernia Esophagus Stomach

25. Gastroesophageal Intussusception

26. Esophagus - Other • Esophageal strictures • Esophageal diverticula • brachycephalic breeds - normal at thoracic inlet • out-pouching of the esophagus • 2° to obstruction, stricture, or vascular ring anomaly

27. Stomach - Anatomy • Cardia, fundus, body, pyloric antrum, pyloric canal • Where are they located??? • Air and fluid are our friends! • Left lateral - air in pylorus, fluid in fundus • Right lateral - air in fundus, fluid in pylorus • VD – Gas in body and pyloric antrum • DV – Gas in the fundus

28. Gastric Displacement • Cranial • Microhepatia • Diaphragmatic hernia • Caudal • Hepatomegaly • Hepatic mass

29. The Normal Stomach

30. FB in pylorus? Um no

31. See how you can move things around?

32. The Gastrogram! • Patient must be fasted! • Contrast Media • Barium suspension (5-8ml/lb) • Organic Iodine (if suspect perforation) • Room Air • All are administered by orogastric tube

33. The Gastrogram! • Double contrast study - 1-2ml/lb Barium suspension followed by 5-10ml/lb of room air • All 4 views are made (VD, DV, both laterals) usually

34. Gastric Dilation/Volvulus • Emergency • Must take both lateral views • stomach distended with gas and fluid • pylorus displaced dorsally and to left • compartmentalization • +/- splenomegaly, +/- hypovolemic changes • Gastric distention without torsion has normal location

35. Popeye Arm = GDV

36. GDV

37. GDV with paralytic ileus

38. GDV – note air in esophagus

39. Gastric Distension (Bloat) • Stomach remains in the normal position but is significantly distended • Often seen after eating abnormal amounts of food • Usually just time to treat – frequent walks - monitor progression of ingesta

40. Gastric Distension

41. Gastric Ulcers • NSAIDS, 2° to other disease processes • Survey films usually normal • Gastrogram • ulcer crater appears as Barium filled plateau projecting away from the lumen • adjacent rugae may be thick • lesser curvature & pyloric region

42. Gastric Neoplasia • ACA, LSA, MCT, LMS • Survey films often normal - may have thick wall or see mass in lumen if surrounded by air • See ulcers, filling defects, static / non-distensible wall • Pythium (fungal disease seen mostly in southern US – similar appearance to neoplasia)

43. Gastric Foreign Body • May see on survey films • Bones, fish hooks, needles • FB’s not in the pylorus appear as filling defects • Porous FB (cloth) retain contrast • Room air can be used • Don’t be afraid to repeat rads • in few hours

44. Gastric FB

45. Dummy

46. Rock FB

47. Sock FB

48. Delayed Gastric Emptying • Pyloric disease • Iatrogenic - Drugs • Stress • Insufficient gastric distention with contrast

49. Pyloric Outflow Obstruction • Survey films show a distended gas and fluid filled stomach • There is delayed gastric emptying of contrast and the pylorus is narrowed • gastric FB’s, plyoric spasms, pyloric hypertrophy, pyloric neoplasia • Ultrasound good to visualize this

50. Chronic Pyloric Obstruction