Xray in surgical practice

1. Welcome to Morning CME
Dr.Md.Saleh
MBBS
MS PHASE-B (General Surgery)
FCPS P-1 (Orthopaedics Surgery)
Medical Officer, Surgery Department
Central Police Hospital, Rajarbag ,Dhaka

2. Topic
Xray in surgical practice

3. Xray in surgical practice
Abdominal Xray
Xray KUB region

4. Approach to AXR
• Bowel gas pattern
• Extra luminal air
• Calcifications
• Ascites
• Organomegaly
• * Nowadays replace by USG

5. Normal AXR
11th rib
Hepatic flexure
Gas in
stomach
T12
Gas in caecum
Iliac crest
Femoral head
SI joint
Gas in sigmoid
Transverse colon
Splenic flexure
Psoas margin
Sacrum
Left kidney
Liver
Bladder

6. Gas pattern
What is normal?
• Stomach
– Almost always air in stomach
• Small bowel
– Usually small amount of air in
2 or 3 loops
• Large bowel
– Almost always air in rectum
and sigmoid
– Varying amount of gas in rest of large bowel

7. Normal fluid levels
• Stomach
– Always (upright, decub)
• Small bowel
– Two or three levels
acceptable (upright, decub)
• Large bowel
– None normally
(functions to remove fluid)

8. Large vs small bowel
• Large bowel
– Peripheral (except RUQ occupied by liver)
– Haustral markings don’t extend from wall to wall
• Small bowel
– Central
– Valvulae conniventes extend across lumen and are
spaced closer together

9. 3, 6, 9 RULE
Maximum Normal Diameter of bowel
Small bowel 3cm
Large bowel 6cm
Caecum 9cm

10. Large vs small bowel

11. Abnormal Gas Patterns
• Functional ileus/ Adynamic
– One or more bowel loops become aperistaltic usually
due to local irritation or inflammation
• Localised “sentinel loops” (one or two loops)
• Generalised (all loops of large and small bowel)
• Mechanical obstruction/ Dynamic
– Intraluminal or extraluminal
• Small bowel obstruction
• Large bowel obstruction

12. Localised ileus
•
•
•
•
•
Key features
One or two persistently dilated
loops of small or large bowel
(multiple views)
Often air-fluid levels in sentinel
loops
Local irritation, ileus in same
anatomical region as
pathology
Gas in rectum or sigmoid
May resemble early SBO

13. Causes of Localised Ileus
by location
SITE OF DILATED LOOPS CAUSE
Right upper quadrant
Left upper quadrant
Right lower quadrant
Left lower quadrant
Mid-abdomen
Cholecystitis
Pancreatitis
Appendicitis
Diverticulitis
Ulcer or kidney/ureteric calculi

14. Colon cut off sign
Abrupt cutoff of colonic gas column at the splenic flexure (arrow). The colon is
usually decompressed beyond this point.
Explanation:
Inflammatory exudate in acute
pancreatitis extends into the
phrenicocolic ligament via lateral
attachment of the transverse
mesocolon
Infiltration of the phrenicocolic
ligament results in functional
spasm and/or mechanical
narrowing of the splenic flexure at
the level where the colon returns
to the retroperitoneum.

15. Generalised ileus
Key features
• Entire bowel aperistaltic/hypoperistaltic
• Dilated small bowel and large bowel to rectum
(with LBO no gas in rectum/sigmoid)
• Long air-fluid levels
CAUSE REMARK
*Postoperative Usually abdominal surgery
Electrolyte imbalance Diabetic ketoacidosis
* almost always

16. Generalised adynamic ileus
The large and
small bowel are
extensively airfilled
but not dilated.
The large and
small bowel "look
the same".

17. Mechanical SBO
• Dilated small bowel
• Fighting loops (visible loops, lying
transversely, with air-fluid levels at different
levels)
• Little gas in colon, especially rectum

18. SBO Erect SBO Supine
Air fluid levels

19. Radiological findings

20. Causes of Mechanical SBO
* May be visible on AXR
Adhesions
Hernia*
Malignancy
Gallstone ileus*
Intussesception
Inflammatory bowel disease

21. Step ladder appearance
• Loops arrange
themselves from
left upper to
right lower
quadrant in
distal SBO

22. Double Bubble Sign
Duodenal Atresia

23. Causes of Mechanical LBO
TUMOUR
VOLVULUS
HERNIA
DIVERTICULITIS
INTUSSUSCEPTION

24. Mechanical LBO
• Colon dilates from point
of obstruction
backwards
• Little/no air fluid levels
(colon reabsorbs water)
• Little or no air in
rectum/sigmoid

25. Large bowel obstruction
Bowel loops tend not to
overlap therefore
possible to identify site
of obstruction
Little or no gas in small
bowel if ileocaecal valve
remains competent*
* If incompetent, large bowel
decompresses into small bowel, may
look like SBO

26. Volvulus
A volvulus always extends away from the area of twist.
Sigmoid volvulus can only move upwards and usually
goes to the right upper quadrant. Caecal volvulus
can go almost anywhere.

27. Note on volvulus
• Sigmoid colon has its own mesentry therefore
prone to twisting
• Caecum usually retroperitoneal and not prone
to twisting; 20% people have defect in
peritoneum that covers the caecum resulting
in a mobile caecum

28. Radiological findings

29. Coffee Bean Sign
Sigmoid volvulus
Massively
dilated
sigmoid loop

30. Hernia
Lateral decubitus of value
The advantage is that there may be a greater chance of air entering the
herniated bowel because it is the least dependent part of the bowel in the
supine position.

31. Extraluminal air
• TYPES
– Pneumoperitoneum/free air/intraperitoneal air
– Retroperintoneal air
– Air in the bowel wall (pneumatosis intestinalis)
– Air in the biliary system (pneumobilia)

32. Upright film best
• The patient should be positioned sitting
upright for 10-20 minutes prior to acquiring
the erect chest X-ray image.
• This allows any free intra-abdominal gas to
rise up, forming a crescent beneath the
diaphragm. It is said that as little as 1ml of gas
can be detected in this way.

33. Free Air
Causes
• Rupture of a hollow viscus
– Perforated peptic ulcer
– Trauma
– Perforated diverticulitis (usually seals off)
– Perforated carcinoma
• Post-op 5-7 days normal, should get less with successive
studies.

34. Crescent Sign
Free air under the diaphragm
Best demonstrated on
upright chest x rays or
left lat decub
Easier to see under
right diaphragm

35. Chilaiditis sign
•
•
•
May mimic air under
the diaphragm
Look for haustral folds
Get left lat decub to
confirm
In patients who have cirrhosis
or flattened diaphragms due to
lung hyperinflation, a void is
created within the upper
abdomen above the liver. This
space may be filled by bowel. If
this bowel is air filled then it
may mimic free gas.

36. Rigler’s Sign
Bowel wall visualised on both sides due to intra and extraluminal air
Usually large amounts of free air
May be confused with overlapping loops of bowel, confirm with upright view

37. Continuous diaphragm sign
Sufficient
free air, left
and right
hemi-
diaphragms
appear
continous

38. Air in the bowel wall
• Signs
– Best seen in profile producing a linear lucency that
parallels the bowel
– Air en face has a mottled appearance resembling
gas mixed with faeculent material

39. Pneumatosis intestinalis
• Intramural air,
best
appreciated in
profile

40. Air in the biliary tree
• One or two tube-like branching lucencies in
the RUQ, conform to location of major bile
ducts

41. Riglers Triad

42. Location Pattern
Abdominal Calcifications

43. Location
•
•
•
•
•
•
•
•
•
•
•
Vascular
Liver
Gallbladder
Spleen
Pancreas
Lymph nodes
Adrenals
Kidneys
Ureters
Bladder
Prostate

44. Rim-like
• Calcification that has occurred in the wall of a
hollow viscus
– Cysts
• renal, splenic, hepatic
– Aneurysms
• aortic, splenic, renal artery
– Saccular organs
• Gallbladder
• Urinary bladder Calcified hydatid cysts

45. Linear/Track
• Calcification in walls of tubular structures
Aortoiliac calcification
– Arteries
– Fallopian tubes
– Vas deferens
– Ureter

46. Calcified vas deferens

47. Calcified enteric
lymph nodes
Calcified fibroids
Calcified pancreas
Floccular

48. Pancreatic calculi

49. Xray abdomen vs Xray KUB
Xray Abdomen
1.Both dome of diaphragm visible
2.Upper limit of symphysis pubis
3.Both lateral wall of abdomen included
Xray KUB
To reduce xray radiation exposure
1.Upper limit of kidney
2.lower border of symphysis pubis
3.Not including lateral wall of abdomen

51. Renal –ureter-bladder calculi

52. Renal calculi
Pelvicalyceal calcifications

53. Nephrocalcinosis
Uncommonly the renal
parenchyma can become
calcified.
This is known as
nephrocalcinosis, a condition
found in disease entities such
as medullary sponge kidney
or hyperparathyroidism.
Renal calculi
Parenchymal calcification
Flocculent

54. Staghorn Calcification
Renal stones are often small, but if large
can fill the renal pelvis or a calyx, taking on
its shape which is likened to a staghorn.
Tubular

55. Bladder calculi
Lamellar

56. Radiological findings

57. References
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•
•
•
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Herring, W. Learning Radiology 2nd Ed, 2012
Begg, J. Abdominal X-rays Made Easy, 1999
http://www.wikiradiography.com
http://www.radiopaedia.org
http://www.imagingconsult.com
Roche, C et al. Radiographics: Selections from the buffet of food signs in Radiology. Nov 2002, RG,
22, 1369-1384
Young, L. Radiology Cases in Paediatric Emergency Medicine. Vol 1 Ca 2. The Target, Crescent and
Absent Liver Edge Signs.
• Raymond, B et al. Radiographics: Classic signs in uroradiology. RSN 2004
• http://www.swansea-radiology.co.uk Radiology Teaching Site. Introduction to abdominal
radiography
• Mussin, R. Postgrad Med J 2011: 87:274-287. Gas patterns on plain abdominal radiographs
• http://www.radiologymasterclass.co.uk/tutorials/abdo/abdo_x-ray_abnormalities
• Mettler: Essentials of Radiology, 2nd Ed, 2005
• http://www.learningradiology.com/radsigns
• Muharram Food signs in radiology. International Journal of Health Sciences Vol 1 No 1. Jan 2007.

58. THANK YOU