Mithilesh Kumar Medical College kolkata

1. IMAGING MODALITIES
IN INTESTINAL
OBSTRUCTION
By – MITHLESH KUMAR
Third Professional MBBS Part – II
Medical College Kolkata

2. OVERVIEW
• Radiography
• Computed Tomography
• Magnetic Resonance Imaging
• Ultrasonography
• Nuclear Imaging
• Angiography

3. Radiography
• Plain upright abdominal X – Ray
• Conventional barium follow – through
examination and enteroclysis
• Barium enema study

4. Radiological features of plain X - Ray
• Small bowel – straight segments generally central
and lie transversely
• Jejunum – valvulae conniventes, spaced
regularly, concertina or ladder effect
• Ileum – featureless
• Caecum – rounded gas shadow in right iliac fossa
• Large bowel except caecum – haustral folds, spaced
irregularly

5. Some special points
• In intestinal obstruction fluid level appear later than gas shadow as it takes
time for gas and fluid to separate
• In adults, two inconstant fluid levels – one at the duodenal cap and the
other in the terminal ileum may be regarded as normal
• In infants fluid levels in small bowel may be physiological, in this age group
it is difficult to distinguish large from small bowel in the presence of
obstruction because the characteristic features seen in adults are not
present or are unreliable
• In small bowel the number of fluid levels is directly proportional to the
degree of obstruction and to its site, the number increasing the more
distal the lesion
• Limited water soluble enema differentiates large bowel obstruction from
pseudo-obstruction

6. Supine view of the abdomen in a patient with intestinal obstruction.
Dilated loops of small bowel are visible(arrows)

7. Upright view of abdomen in a patient with intestinal obstruction,
Showing multiple air fluid levels

8. Lateral decubitus view of abdomen, showing air fluid levels consistent
with intestinal obstruction (arrows)

9. Plain abdominal radiograph shows dilated loops of small bowel
associated with thickened edematous valvulae conniventes

10. Barium follow - through
Following features may assist in diagnosis
• Delay in the transit time
• Snakehead appearance
• Beak sign
• Fixation and kinking

11. The contrast enhanced study shows dilated loops of small bowel with
stretching of the mucosal folds and a narrowed segment ending in a beak
(arrow)

12. Enteroclysis
Divide small bowel obstruction into 3 groups
• Low – grade or incomplete obstruction
• High – grade obstruction
• Complete small – bowel obtruction

13. Barium enema study
• Useful in large bowel obstruction
• In children with intussusception it is
diagnostic as well as therapeutic

14. Postevacuation image from part of a barium enema study, shows a coiled
spring appearance at the hepatic flexure of the colon typical of an
intussusception

15. Computed Tomography
• Recommended when initial clinical findings
and plain radiographs are inconclusive
• When strangulation is suspected
• Clearly demonstrate abnormalities of bowel
wall, mesentery, mesenteric
vessels, peritoneum
• Should be performed with intravenous
contrast enhancement

16. Axial computed tomography scan showing dilated, contrast filled loops of
the bowel on the patient’s left( yellow arrows), with decompressed distal
small bowel on the patient’s right(red arrows)

17. Magnetic Resonance Imaging
• Assessment of small – bowel obstruction with
strangulation

18. Ultrasonography
• It is of particular value in looking at the
dynamics of the small bowel
• Used to assess peristalsis

19. A sonogram of right iliac fossa shows a bowel mass

20. Nuclear Imaging
• White blood scanning for detection and
localization of intra abdominal inflammatory
disease

21. 99mTc HMPAO labeled white blood cell scan shows active uptake of the
radionuclide in the terminal ileum and caecum/ascending colon
indicative of an active inflammatory process

22. Angiography
• Superior mesenteric angiography used in
diagnosis of internal
herniation, intussusception, volvulus, malrotat
ion, and adhesions.

23. Imaging in Intussusception
• Plain abdominal X – Ray shows features of
small and large bowel obstruction
• Barium follow through of ileocolic
intussusception shows claw sign
• Abdominal ultrasonography demonstrate
doughnut appearance

24. ‘Claw ‘sign of iliac intussusception , the barium in the intussusception is
seen as a claw around a negative shadow of the intussusception

25. Postevacuation image from part of a barium enema study shows a coiled
spring appearance in the region of caecum suggestive intussusception

26. Imaging in Volvulus
Caecal volvulus – bird beak deformity in
barium enema
Sigmoid volvulus – dilated loop

27. Grossly dilated loop of bowel in the central abdomen with the ends of
the loop pointing towards the right half of the pelvis

28. Shows a medially pointed end column of the barium (beak sign) in the
mid ascending colon