1. Radiography of the GI System
Chapter 17
Radiography of the GI System

2. Anatomy Of Digestive System
Alimentary Canal
Mouth
Pharynx
Esophagus
Stomach
Small / Large Intestine

3. Anatomy Of Digestive System
Accessory glands
Liver
Gallbladder
Salivary glands
Pancreas

4. Esophagus
Long muscular tube carries food and saliva from laryngopharynx to stomach
Approximately 10 in. long in adult
Lies in midsagittal plane

5. Esophagus Originates around C-6
In thorax, it is anterior to spine, posterior to trachea and heart
Passes through diaphragm through esophageal hiatus

6. Esophagus Inferior to diaphragm curves sharply left
Increases in diameter
Joins stomach at esophagogastric junction
At level of xyphoid tip
4 layers of the esophagus
Outermost - fibrous
Muscular
Submucosal
Innermost - Mucosal

7. Stomach Dilated saclike portion of digestive tract
Composed of same 4 layers as esophagus
Outermost - fibrous
Muscular
Submucosal
Innermost - Mucosal

8. Stomach (cont’d) Divided into 4 parts
Cardia
Fundus
Body
Pyloric portion
Entrance to stomach is cardiac orifice
Controlled by cardiac sphincter
Exit is the pyloric orifice
Controlled by pyloric sphincter

9. Stomach (cont’d) Body Begins at cardiac notch Contains rugae
Terminates at angular notch
Pyloric portion
Consists of pyloric antrum and canal
(antrum: cavity or chamber)

10. Body Habitus - Effect On Positioning
Hypersthenic
Horizontal and superior
Dependent portion above umbilicus
Asthenic
Vertical and inferior
Sthenic
Generally found between xyphoid process and iliac crest

11. Functions Of Stomach Breaks down food chemically
Broken down material is called?
chyme
A storage area for further digestion

12. Small Intestine Extends from pyloric sphincter to ileocecal valve
Joins large intestine at right angle
Digestion and absorption of food occur in small intestine
Approximately __ feet in length in adult 22

13. Small Intestine Contains same four layers as stomach and esophagus
Mucosa contains projections called villi to facilitate digestion and absorption
Divided into 3 parts:
Duodenum
Jejunum
Ileum

14. Duodenum Contains 4 regions 8 - 10 inches in length
Widest portion of small intestine
Follows a C-shaped course
Contains 4 regions
Superior, descending, horizontal, ascending

15. Jejunum And Ileum Jejunum Ileum
Upper remaining 2/5 of small bowel
Ileum
Terminates at ileocecal valve
Both are gathered into freely movable loops (gyri)
Attached to posterior abdominal wall by mesentary
(the double layer of peritoneum)

16. Valvulae conniventes
Muscular bands encircling small bowel usually seen to traverse bowel wall at right angles to long axis of the bowel

17. Large Intestine What is the main purpose?
Reabsorbs fluids and eliminate waste products
About _____ feet in length in adult 5
Greater in diameter than small intestine
Contains same four layers as esophagus, small intestine, and stomach
Which are?

18. Portions Of Large Intestine
Cecum
Ascending
Joins transverse colon at right colic flexure
Transverse
Descending
Joins transverse colon at left colic flexure
Sigmoid
Rectum
Anal canal

19. Large Intestine
The muscular portion contains external bands of muscle known as taeniae coli
These bands create a series of pouches known as?
haustra

20. Compare
Valvulae conniventes
Small bowel
Haustra
Large bowel

21. Variations In Body Habitus
Hypersthenic
Colon lies in periphery of abdomen
May need double films!
Asthenic
Intestines are bunched together in lower abdomen

22. Radiographic Exams

23. Contrast Media Barium sulfate Water insoluble Iodinated contrast media
Water soluble
Horrible taste
Does not adhere to wall of alimentary tract
Indicated in case of perforation

24. Contrast Media Air Considered a negative contrast
Generally administered by carbon dioxide crystal ingestion
Barium and Air are often used as a double contrast agent

25. Preparing pt. for GI study
Have contrast agents mixed and ready to go
Explain exam to pt.
Ensure pt. has followed preparation instructions!

26. Preparation cont’d Ensure that footboard is securely on table!
Use short exposure times
Use high kVp to penetrate barium
Take exposures end of full expiration!

27. Radiography Of Esophagus
Can use double or single contrast
Barium should flow to sufficiently coat esophagus
Can be done upright or recumbent
Exam will usually be started with fluoroscopy

28. AP or PA Projection Pt. supine or prone
Center midsagittal plane to cassette
Bottom of cassette should be placed just below tip of xyphoid
Pt. drinks contrast before exposure and continues drinking during exposure
Shield!

29. RAO or LAO Positions Pt should be rotated 35 - 40 degrees
Center about 2 inches lateral to MSP
Bottom of cassette below xyphoid

30. RAO or LAO Positions Pt must drink before and during exposure
Use shielding!

31. Lateral Projection Place pt in lateral position
Center midcoronal plane to cassette
Bottom of cassette below xyphoid process
Pt must drink continuously before and during exposure
Use shielding!

32. Structures Shown/Film Evaluation
Entire barium filled esophagus from lower neck to stomach
Barium should be sufficiently penetrated
Surrounding structures should be visible, not overpenetrated
No rotation on AP, PA, or lateral projections
Esophagus should be displayed between heart and spine on oblique projections

33. What is the Valsalva Maneuver?
Useful in demonstrating esophageal varices
Have pt. first deeply inspire
Swallow contrast
Bear down
Recumbent position

34. Esophageal varices
Extremely dilated sub-mucosal veins in the lower esophagus
Most often a consequence of portal hypertension, commonly due to cirrhosis
Pts with esophageal varices have a strong tendency to develop bleeding

35. Radiography Of The Stomach
Upper GI Series
Generally consists of fluoroscopy and serial radiographs
Single or double contrast
Pt. should follow a low residue diet for 2 days prior to exam
Pt. must be NPO after midnight
AP scout generally obtained prior to exam

36. UGI Positioning - AP Projection
Supine CR
MSP at L1-L2
Between MSP and left side if using small film
At MSP if using 14 X 17
Structures
Barium filled fundic portion
Hiatal hernias, if present

37. Single v. Double Contrast
Single Contrast
Shows size, shape, and position of stomach
Examines changing contour of stomach during peristalsis
Observe filling and emptying of duodenal bulb

38. Double Contrast Mucosal lining is well visualized
Small lesions are less easily obscured

39. Compare Single and Double Contrast

40. Which is taken AP and which is taken PA?

41. UGI Study - PA Projection
Prone Position
Center at MSP if using 14 X 17 CR
Perpendicular to plane of film at level of L1-L2

42. UGI study - PA Projection
Structures shown?
Size, shape, and relative position of stomach
Evaluation:
All pertinent anatomy
No rotation
Exposure sufficient to penetrate barium
Surrounding structures visible

43. UGI Positioning - PA Oblique Projection
Recumbent
Body rotated degrees
Hypersthenic patients require more rotation CR
Perpendicular to L1-L2
Between vertebral column and elevated lateral border of the abdomen

44. UGI Positioning - PA Oblique Projection
Structures
Entire duodenal loop
Best image of pyloric canal and duodenal bulb
Evaluation
All pertinent anatomy
No superimposition of pylorus and duodenal bulb
Duodenal bulb and loop in profile

45. UGI Positioning - AP Oblique Projection
Supine
Right side elevated degrees
Average about 45 degrees CR
Between vertebral column and left lateral border at L1-L2
Structures
Fundic portion of stomach filled with barium
Evaluation
All pertinent anatomy
No superimposition of pylorus and duodenal bulb
Barium filled fundus

46. Lateral Projection Position Lateral recumbent - right side CR
Level of L1-L2
Between midcoronal and anterior of abdomen

47. Lateral Projection
Structures
Pyloric canal and duodenal bulb in hypersthenic patients
Evaluation
No rotation
All pertinent anatomy

48. Small Bowel Follow Through
Preparation
Low residue diet for 2 days prior when possible
NPO after midnight before exam
Examination Procedure
Scout film obtained
Patient drinks barium
Images obtained in prone or supine position
Images begin 15 minutes after barium ingested
Barium usually reaches ileocecal valve in about 2 -3 hours

49. Radiography Of Small Intestine
Contrast administration 3 Ways
Orally
Retrograde
Reflux filling via barium enema
Direct injection of contrast through NG tube
Enteroclysis (Radiocontrast is infused through tube inserted through nose to duodenum, and images are taken in real time as contrast moves through)

50. Small Bowel - AP/PA Projection
Patient supine or prone
CR centered to level of L2 for early films
Iliac crest for later films
Continue taking radiographs until barium reaches terminal ileum
Fluoroscopic spot films may be taken of terminal ileum

51. Small Intestine Follow Through
15 minutes
Immediate

52. Small Intestine Follow Through
1 hour
30 minutes

53. T.I.
Demonstrates Ileocecal Valve

54. Radiography Of Colon

55. Preparation of Colon Pt must take laxative on day prior to exam
Pt may have clear liquid day prior to exam
NPO after midnight
Cleansing enemas may also be indicated

56. Pt. Preparation Explain exam fully to pt.
Use care when inserting enema tip!
Retention-type balloon tips should only be inflated under fluoroscopic control
Barium should only be administered under fluoroscopic control by radiologist

57. Single or double contrast
Single demonstrates anatomy and tonus (contraction) of colon, along with most abnormalities
Feces

58. Double Contrast
Double allows visualization of lumen along with any polyps or lesions

59. AP Projection - Barium Enema
Supine
MSP centered to cassette
CR at iliac crest
Entire colon must be included
Two cassettes are sometimes necessary

60. PA Projection - Barium Enema
Pt. prone
MSP centered to film
CR at iliac crest
Entire colon must be visualized
Barium should be sufficiently penetrated with surrounding structures visible

61. PA Axial Projection - BE
Pt. prone
MSP centered to IR
CR directed degrees caudal to ASIS
Demonstrates rectosigmoid area of colon
Area must be centered to IR

62. PA Axial Projection - BE

63. AP Oblique Projection - BE
Pt. Supine
Body rotated degrees
CR in. lateral to midline at iliac crest

64. AP Oblique Projection - BE
LPO - Right colic flexure, ascending and sigmoid portions of colon
RPO - Left colic flexure, descending colon
Must demonstrate entire colon
Which oblique is this?

65. PA Oblique Projection (RAO)- Barium Enema
Pt. prone
Left side elevated degrees
CR at iliac crest, 1 -2 inches lateral to midline of body

66. PA Oblique Projection (RAO)- Barium Enema
Best demonstrates hepatic flexure
Ascending and sigmoid portion
Entire colon must be visualized
What projection is this similar to?

67. PA Oblique (LAO) - BE Pt. prone Right side elevated 35 - 45 degrees
CR to iliac crest, inches lateral to midline

68. PA Oblique (LAO) - BE Demonstrates descending portion of colon
Entire colon must be visualized
What flexture doe this best demonstrate?
(splenic)
What projection is it comparable to?

69. Lateral Projection - Barium Enema
Lt. or Rt. lateral recumbent position
Center midcoronal plane to film
CR enters midcoronal plane at level of ASIS

70. Lateral Projection - Barium Enema
Best demonstrates rectum and distal sigmoid portions of colon
Rectosigmoid area should be centered, no rotation

71. Lateral Decubitus Positions - BE
AP or PA projection

72. Left Lateral Decubitus Positions - BE
Up side is air-filled
Must include entire colon
Air-filled portion must not be overpenetrated

73. Upright Position - Barium Enema
Demonstrates air-filled flexures and transverse colon

74. Chassard Lapine’
Demonstrates rectum, rectosigmoid juntion and sigmoid

75. What is a Defecography? (evacuation proctography)
Radiographic exam of defecation process under fluoroscopy
Used to evaluate disorders of lower bowel not evident by tests such as colonoscopy or sigmoidoscopy

76. Defecation
(Having a bowel movement) is a complex action requiring coordination with relaxation and contraction of a large number of muscles
Controlled by nervous system, but is also under voluntary control.

77. Defecation cont’d Process is initiated by arrival of stool into rectum
This sensation leads to chain of events which ends in evacuation of stool from anus
Defecation is voluntarily controlled in healthy, normally functioning people.

78. Defecography is used to Evaluate:
Chronic Constipation
Rectal prolapse (walls of rectum protrude through anus and become visible outside body)
Rectocele (outpouching of rectum)
Fecal incontinence
Anismus (inappropriate spasm of anal sphincter)

79. Defecography A thickened barium contrast putty is injected into rectum
then excreted by patient while radiologist watches and videotapes