Radiology of the Vomiting Child

1. Radiology of the Vomiting Child Steven T Welch, MD Children’s Mercy Hospital April 30, 2011

2. Vomiting/ Regurgitation in young children • Most common cause of vomiting and regurgitation in infants is gastroesophageal reflux. • These patients typically maintain normal weight and developmental milestones.

3. Natural history of infant regurgitation • 47% of 1 month old infants had 1 or more daily episodes of vomiting/regurgitation, decreased to 29% at 4 mos, and 6% at 7 mos. • Miyazawa et al, “International Pediatrics”, 2002. • Spilling of feeds reached peak prevalence of 41% between 3 and 4 mosand decreased to less than 5% by 13 mos. • Martin et al, “Pediatrics”, 2002.

4. Reflux in esophagus Stomach Upper GI study

5. Vomiting/ Regurgitation in young children • Most patients do NOT require imaging with an upper GI exam as this study defines anatomy, and reflux may or may not be seen. • In cases of persistent or severe regurgitation, pH probe monitoring may be helpful. • Imaging should be considered if there are airway symptoms or bloody or bilious emesis.

6. pH probe in esophagus

8. What test should be ordered for a child with bilious emesis? • Esophagram • Upper GI/small bowel follow-through • OPM (oropharyngeal motility) • Upper GI study

9. Vomiting/ Regurgitation in young children • It is NOT necessary to order a small bowel follow-through examination to exclude malrotation because the pediatric upper GI examination includes imaging of the ligament of Treitz.

10. Newborn Bilious Emesis • Bilious emesis in a newborn is an emergency which should be promptly evaluated with an upper GI examination to exclude malrotation and volvulus. • Patients should have an NG or OG tube placed to confirm the presence of bilious material as well as facilitating the UGI exam.

11. Supine abdomen Left lateral decubitus view stomach

12. Upper GI study Left pedicle line Duodenojejunal junction

13. Upper GI study Volvulus

14. Normal duodenojejunal junction (ligament of Treitz)

15. Pyloric Stenosis • Common cause of early infantile intestinal obstruction. • Also known as Hypertrophic Pyloric Stenosis (HPS). • Multifactorial causes suggested including: • Hereditary • Exposure to macrolide antibiotics (erythromycin) • Abnormal myenteric plexus innervation • Infantile hypergastrinemia

16. Pyloric Stenosis • 2-4 cases/ 1000 live births in U.S., male:female ratio 4:1 • 95% diagnosed between 3 and 12 weeks of age. • Nonbilious emesis which becomes projectile. • May have a palpable “olive” on exam.

17. In cases of suspected pyloric stenosis, the best radiology study to order is: • Upper GI study • KUB (abdXray) • Ultrasound • Computed tomography (CT)

18. Pyloric Stenosis • A limited abdominal ultrasound is the diagnostic study of choice. • Highly sensitive and specific • No radiation • No sedation

19. Pyloric Ultrasound Elongated pyloric channel Thickened pyloric muscular wall

20. Pyloric Stenosis • Individual wall thickness > 3mm • Elongated pyloric channel >18mm • Mucosal hypertrophy • Absence of fluid or gas in the pyloric channel during the US study.

21. Upper GI study Elongated, narrow pyloric channel Contrast filled stomach

22. Intussusception • Most common cause of intestinal obstruction in children aged 3 to 36 mos., 60% < 1 y.o., 80% < 2 y.o. • Majority are idiopathic. • Seasonal patterns associated with gastroenteritis, possibly due to hypertrophy of lymphoid tissue in the terminal ileum. • Increased incidence after some forms of rotavirus vaccine.

23. Intussusception • Pathologic lead point in some cases: • Meckel’sdiverticulum • Enteric duplication cyst • Lymphoma • Polyps • Henoch-Schonleinpurpura (intramural hemorrhage)

24. Intussusception • Present with sudden onset of crampy, intermittent abdominal pain with drawing-up of legs and inconsolable crying. • May develop vomiting and currant-jelly stools. • Diagnostic work-up includes abdominal radiographs and ultrasound. • Treated with air enema reduction.

25. Why order plain x-rays in suspected cases of intussusception? • Look for obstruction. • Exclude free air. • May suggest an alternative diagnosis. • All of the above.

26. Supine abdomen X-ray Left decubitus X-ray

27. Abdominal Ultrasound Ileocolicintussusception

28. Air enema reduction

29. Intussusception • Contraindications to enema reduction: • Pneumoperitoneum • Clinical peritonitis or unstable patient • Surgery required for incomplete reduction, free air, multiple recurrent episodes (possible lead point). • Incidental small bowel-small bowel intussusception which may be seen on US or CT is typically transient and asymptomatic.

30. Less common causes of obstruction Newborn presentation: • Meconiumileus • Small bowel atresia • Meconium plug (small left colon) syndrome • Hirschprung’s disease

31. Stomach Multiple dilated bowel loops

32. Filling defects in terminal ileum on contrast enema

33. Meconiumileus

34. Upright Abdomen X-Ray Supine Abdomen X-Ray

35. Delayed image from Upper GI study Dilated distal small bowel loops

36. Ilealatresia

37. Multiple dilated bowel loops suggesting distal bowel pathology

38. Contrast Enema Small left colon Meconium plugs

39. Meconium Plug Syndrome

40. Multiple dilated bowel loops suggesting distal obstruction.

41. Lateral view from a contrast enema Dilated sigmoid colon Narrowed, irregular rectum

42. Hirschprung’s disease

43. Additional causes of obstruction • Older infants and children: • Appendicitis • Adhesions • Incarcerated hernia • Meckel’sdiverticulum

44. Appendicolith

45. Appendix Ultrasound Shadowing stone in dilated appendix

46. Appendix Ultrasound • Ordered as a limited abdominal US. • Linear transducer with graded compression. • Non-compressible, blind-ending tubular structure, >6mm • Often surrounded by edema/inflammation.

47. Appendicitis CT Stone within an inflamed appendix

48. Inguinal hernia noted on physical exam; Gas-filled bowel loops seen on X-Ray performed for vomiting.

49. Incarcerated Hernia

50. Abnormal fluid filled structure on Pelvis CT