1. Radiological Interpretation Gastrointestinal System
Reference notes: Radiology and Images for students – British medical Journal

2. Different Modalities of abdominal radiograph
Plain abdominal radiograph (AXR)
Contrast abdominal x ray films
Ultrasound abdomen
Computed Tomography of abdomen (CT)
MRI
Other interventional methods - ERCP

3. Today’s Session Plain abdominal radiograph (AXR)
Contrast abdominal x ray films
Computed Tomography of abdomen (CT)

4. Systematic approach of reading a plain AXR
Technical details (preliminary information)
Type or View of the x – ray film
Look for abnormal Intra and Extra luminal gas
Calcification
Soft tissue (Solid organs) abnormalities
Bony abnormalities

5. Technical details Name , Age and Sex of the patient
Date on which the film was taken
Purpose:
To ensure that you interpret the results of the correct patient

6. Type of the AXR Three types:
Supine films: Taken when patient is supine position
Most commonly requested film
Erect films: Only during some situations
Visualization of air-fluid level
Decubitus: Taken when patient is lying on his side (right or left)

7. Key to densities in AXRs
Black – gas
White – calcified structures
Grey – soft tissues
Darker grey – Fat
Intense white – Metallic objects

9. Characteristics of Bowel loops
Small bowel
Size : < 3 cm
Location: central
Presence of Valvulae conniventes
(Seen well when dilated)
Large bowel
Size : < 5 cm (Except caecum <9 cm)
Location: Periphery
Presence of Haustrations
(Seen well when dilated)

10. Intra luminal Gas (Gas within the lumen of bowel)
Normal
Visibility depends on the amount of air
Places to look for normal bowel gas are
Stomach (Gastric air bubble)
Intestine ( mc - caecum and rectum)
Abnormal
Should satisfy the criteria
Due to Intestinal obstruction

11. Comparison of large and small bowel obstruction radiological features
Bowel diameter: > 3 cm and < 5 cm
Position: Central
No. of loops: many loops
Fluid level on erect film: many, short
Bowel markings: Valvulae conniventes (all the way across)
Large bowel
> 5 cm (Except caecum > 9 cm)
Peripheral
Few
Few, long
Haustrations (partially across)

12. Small bowel
Bowel diameter: > 3 cm and < 5 cm
Position: Central
No. of loops: many loops
Fluid level on erect film: many, short
Bowel markings: Valvulae conniventes (all the way across)

13. Volvulae Conniventes
Volvulae Conniventes

14. Small bowel obstruction
Adhesions (60%)
Hernias (10%)
Crohn’s disease
Neoplasms (20%)
Intussusception
Volvulus
Intestinal atresia
Foreign body

15. Comparison of large and small bowel obstruction radiological features
Large bowel
> 5 cm (Except caecum > 9 cm)
Peripheral
Few
Few, long
Haustrations (partially across)

17. Common Causes of LBO Colon cancer Diverticulitis Volvulus Hernia
Unlike SBO, adhesions very unlikely to
produce LBO
frequency

18. Multiple air
fluid levels

19. Extra luminal gas (Gas outside the bowel)
Called as Pneumoperitoneum
Site to look for pneumoperitoneum under the right diaphragm (“air under diaphragm”)
Most important and potentially devastating finding
Indicates perforated viscus (most common)
Emergency surgical intervention is necessary and life saving

22. Conditions causing extra luminal air
Perforated abdominal viscus
Abscesses (Subphrenic – most common)
Biliary fistula
Necrotizing enterocolitis

23. Calcifications Normal structures that calcify
Abnormal structures that contain calcium

24. Normal structures that calcify
Costal cartilage
Mesenteric lymph nodes
Pelvic vein clots (Phlebolith)
Prostate gland

25. Abnormal structures that contain calcium
Calcium indicates pathology:
Pancreas
Renal parenchyma
Blood vessels and vascular aneurysms
Gall bladder fibroids
Calcium is pathology
Biliary calculi
Renal calculi
Appendicolith
Bladder calculi

26. Vascular calcification
Renal calcifications-nephrocalcinosis
Calcified uterine fibroid

27. Systematic approach to a contrast radiograph
Special radiographs taken after ingestion of contrast material called barium
To make the gut show up very well in some situations
Part of the intestine to be examined decides the type of barium test

28. Barium sulfate
Barium sulfate is a white crystalline powder with molecular weight of 233 and specific gravity of 4.5
Four ranges of barium sulfate concentrations are in common use
Dilute 20-25%w/v barium for single contrast enemas
Dense % barium for air contrast enemas
Medium density 65-70%w/v for BMFT
High density %w/v for UGI

29. Fluoroscopy machine

30. Types of the Barium tests
Barium Swallow
Barium Meal
Barium follow through
Small intestines enema
Single contrast enema

31. Indications – most important
Suspected obstruction
Suspected calculus in any viscus
Palpable abdominal mass (malignancy)

32. Subject preparation
Subject takes clear fluids the day before the examination
At 5.00 pm administer magnesium citrate
At pm ask the subject to take 4 tablets of dulcolax with one full glass of water

33. On the day of the procedure
Nil per oral until the procedure is completed
Administration of a dulcolux suppository

34. Barium swallow A fruit flavoured barium liquid is taken to the subject
An AP or PA view of x – ray pictures are taken during swallowing
The whole procedure takes 10 mins
Purpose:
Clinical conditions related to oesophagus and stomach can be visualized

35. Barium swallow indications
Dysphagia
Food or liquid getting stuck while swallowing
Sensation of lump in the throat
Pain during swallowing

36. Barium swallow

37. Normal impressions on the esophagus

39. Carcinoma esophagus Irregular narrowing mid esophagus
‘Apple core’ appearance
Shouldering
Soft tissue mass

40. Barium Meal Steps of the procedure are similar to barium swallow
Purpose:
Clinical conditions related to stomach and duodenum can be visualized better

41. Barium meal

44. Barium follow through Preliminary steps are similar to barium swallow
Films are taken after 10 to 15 mins
Purpose:
Clinical conditions related to small intestines like ulcers, polyps and tumours can be visualized

45. Barium meal follow through

46. Barium enema indications
Change in bowel habit
Melena or blood in the stools
Change in the shape of stools, pencil stools
Anemia
Previous h/o bowel cancer or polyps
Family h/o bowel cancer or polyps
Unexplained weight loss

48. Double contrast barium enema

49. CT abdomen
Students expected to identify the normal abdominal viscera, vascular and bony structures

50. Indication To assess equivocal imaging findings
Staging of hepatic neoplasm
Diagnosis of abdominal masses
Assessment of bliliary problems
Diagnosis vascular lesions
Assessment of suspected post traumatic complications

51. Computed tomography

53. stomach
spleen

54. Left lobe
Right lobe
spleen

55. GB
pancreas DC
adr
adr
spleen
Adr= adrenal gland
DC= descending colon

56. adrenal

57. Case 1:
This 67 year-old women presented to the surgical ward with a distended abdomen and vomiting.
Present this x-ray
Give a diagnosis and potential causes