(1) The document provides guidance on interpreting abdominal x-rays. It describes the proper positioning and views needed, and outlines the anatomy and structures that should be evaluated. This includes the lungs, liver, gallbladder, stomach, spleen, kidneys, bones and other organs. (2) Examples of significant abdominal conditions that can be identified on x-ray are provided. This includes free air under the diaphragm indicating a perforation, small or large bowel obstructions seen as dilated loops of bowel, and volvulus appearing as a U-shaped dilated loop of bowel. Toxic megacolon from colitis is described as transverse colon dilation of 6cm or more. (3

1. Abdominal X-Ray
2021
Dr Pramisesh Premadish
MBBS – Fiji National University

2. General
• X-rays of the abdomen are usually taken with the patient lying
down; erect views are taken only when the clinical diagnosis is
“Acute Abdomen”. (1)
Note: The diaphragm must be visible above and the pubic
symphysis below. (1)

3. Anatomy (2)

4. Approach
• Identification
• Technically correct
• Position
• View
• Exposure : The bones of the spine should be discernible (3)

5. Air
• Within the lumen? Vs. Free gas?

6. Air/gasunderthediaphragm(4)

7. Rigler sign ( Normal )

8. FootballSign(4)

9. Bowels
• Any part of the bowel may be visible if it contains gas/air within
the lumen
• 3/6/9 rule
• Bowel wall inflammation

10. OtherStructuresand Organs
• Lungs – Don’t miss a consolidation or effusion !
• Liver – Hepatomegaly - is inferred when there is
extension of the right lobe inferior to the lower
pole of the right kidney. Liver silhouette is
enlarged, displacing bowel loops medially.
• Gallbladder – Rarely seen. Stones? Clips?
• Stomach - may be visible if it contains gas/air.
• Spleen

11. OtherStructuresand Organs(Cont.’)
• Kidneys – The sensitivity and specificity of plain
abdominal films in detecting a stone is low.
• “Sensitivity is reduced for stones <3 mm, which might not
produce a shadow, and stones can be missed in a decompressed
system owing to the difficulty in distinguishing echogenic stones
from echogenic central sinus fat in the kidney. Sensitivity can be
improved by combining ultrasonography with KUB radiography.”
(Brisbane, Bailey and Sorensen, 2016)
• Psoas muscles
• Bladder

12. Bones
• Ribs
• Pelvis
• Proximal femurs
• Thoracic and Lumbar vertebrae
• Sacrum / coccyx

13. Calcificationand Artefacts
(Abdominal X-ray Interpretation (AXR) |
Radiology | OSCE | Geeky Medics, 2021)

14. Remember

15. Significant Abdominal
Conditions

16. (1)
• 34 year old male, presented to Emergency department
with abdominal pain ,multiple episodes of non bilious
vomiting and fever for 1 day duration, not passed flatus and
stool since 2 days. No trauma.
• BP:106/60 HR:110/min, RR: 20/min ,afebrile.
• On examination, abdo. distended , diffuse abdominal
tenderness, guarding and rigidity present , bowel sounds were
absent.

18. ∆ intraperitoneal free air

19. (2) Bowel Obstruction

20. ∆ Large bowel obstruction

21. • As a general rule, the more visible the small bowel is,
the more likely it is to be pathological.
• Small bowel can be identified by its central location
within the abdomen and the characteristic valvulae
conniventes that traverse the small bowel lumen.
• This is in contradistinction to the haustral folds that
do not span the entire diameter of the colonic wall.
• The normal small bowel should not exceed 3cm.
• Large bowel obstruction is recognised by dilatation of
the colon to more than 6cm or more than 9cm for
the caecum.

22. Volvulus
U-shape loop of dilated bowels. The
walls of the affected loops forms the
classic ‘coffee bean sign’, which can
be extremely large and occupy most
of the abdominal radiograph.

23. Toxic Megacolon

24. • Toxic megacolon can develop in patients with
colitis.
• The classic radiographic finding in toxic
megacolon is dilatation of the transverse colon
to 6cm or more but it can also be indicated by
progressive colonic distension on serial
radiographs.

25. References
• 1) Sandström, S. and Ostensen, H., 2003. The WHO manual of diagnostic imaging.
Geneva: WHO.
• 2) Pinterest. 2021. Abdominal Radiographic Anatomy - wikiRadiography | Medical
radiography, Radiology humor, Radiology imaging. [online] Available at:
<https://www.pinterest.com/pin/476185360582554159/> [Accessed 7 April 2021].
• 3) Burbridge, B., 2021. Approach to the Abdominal X-ray (AXR). [online]
Undergradimaging.pressbooks.com. Available at:
<https://undergradimaging.pressbooks.com/chapter/approach-to-the-abdominal-x-ray-
axr/> [Accessed 7 April 2021].
• 4) -, D., 2021. Abdominal X-ray - Abnormal bowel gas pattern - Free
gas/pneumoperitoneum. [online] Radiologymasterclass.co.uk. Available at:
<https://www.radiologymasterclass.co.uk/tutorials/abdo/abdomen_x-
ray_abnormalities/pathology_bowel_gas_perforation> [Accessed 7 April 2021].
• 5) ResearchGate. 2021. Fig. 4 Supine abdominal radiograph demonstrates Rigler's
sign.... [online] Available at: <https://www.researchgate.net/figure/Supine-abdominal-
radiograph-demonstrates-Riglers-sign-arrowheads-of-
pneumoperitoneum_fig2_232247508> [Accessed 7 April 2021].
• 6) Jones, J., 2021. Normal abdominal x-ray (large bowel gas) | Radiology Case |
Radiopaedia.org. [online] Radiopaedia.org. Available at:
<https://radiopaedia.org/cases/normal-abdominal-x-ray-large-bowel-gas> [Accessed 7
April 2021].

26. References (Cont.’)
• 7) Shah, V., 2021. Abdominal x-ray organs (summary) | Radiology Reference
Article | Radiopaedia.org. [online] Radiopaedia.org. Available at:
<https://radiopaedia.org/articles/abdominal-x-ray-organs-summary>
[Accessed 8 April 2021].
• 8) Jones, J., 2021. Hepatomegaly (abdominal x-ray) | Radiology Case |
Radiopaedia.org. [online] Radiopaedia.org. Available at:
<https://radiopaedia.org/cases/hepatomegaly-abdominal-x-ray> [Accessed 8
April 2021].
• 9) -, D., 2021. Abdominal X-ray - System and anatomy - Bowel gas pattern.
[online] Radiologymasterclass.co.uk. Available at:
<https://www.radiologymasterclass.co.uk/tutorials/abdo/abdomen_x-
ray/anatomy_system_bowel_gas> [Accessed 8 April 2021].
• 10) Brisbane, W., Bailey, M. and Sorensen, M., 2016. An overview of kidney
stone imaging techniques. Nature Reviews Urology, 13(11), pp.654-662.
• 11) cleveland. 2021. Bobcat spotted in Summit Metro Park in Richfield.
[online] Available at: <https://www.cleveland.com/news/2021/02/bobcat-
spotted-in-summit-metro-park-in-richfield.html> [Accessed 8 April 2021].
• 12) Geeky Medics. 2021. Abdominal X-ray Interpretation (AXR) | Radiology |
OSCE | Geeky Medics. [online] Available at:
<https://geekymedics.com/abdominal-x-ray-interpretation/> [Accessed 8 April
2021].

27. References (Cont.’)
• 13) Med.unc.edu. n.d. Abdominal xrays made easy: normal radiographs.
[online] Available at: <https://www.med.unc.edu/medclerk/wp-
content/uploads/sites/877/2018/10/AXReasy1.pdf> [Accessed 8 April 2021].
• 14) Barry James, B., 2021. The Abdominal Radiograph. [online] PubMed
Central (PMC). Available at:
<https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3913410/> [Accessed 8
April 2021].
• 15) Medcraveonline.com. 2019. Idiopathic pneumoperitoneum presenting
as acute abdomen. [online] Available at:
<https://medcraveonline.com/MOJCR/MOJCR-09-00317.pdf> [Accessed 8
April 2021].
• 16) Cadogan, M., n.d. AXR Interpretation • LITFL • CCC Investigations.
[online] Life in the Fast Lane • LITFL. Available at: <https://litfl.com/axr-
interpretation/> [Accessed 8 April 2021].
• 17) Babu, V., 2021. Large bowel obstruction | Radiology Case |
Radiopaedia.org. [online] Radiopaedia.org. Available at:
<https://radiopaedia.org/cases/large-bowel-obstruction> [Accessed 8 April
2021].
• 18) En.wikipedia.org. n.d. Sigmoid colon volvulus - Wikipedia. [online]
Available at: <https://en.wikipedia.org/wiki/Sigmoid_colon_volvulus>
[Accessed 8 April 2021].

28. References (Cont.’)
• 19) PhotoDune. n.d. Coffee bean macro isolated. [online] Available at:
<https://photodune.net/item/coffee-bean-macro-isolated/24889884>
[Accessed 8 April 2021].
• 20) Quizlet. n.d. Toxic megacolon. [online] Available at:
<https://quizlet.com/518023177/toxic-megacolon-flash-cards/> [Accessed 8
April 2021].

29. Thank You.