The Pediatric Abdomen: Intussusception

1
The Pediatric AbdomenIntussusception

• Mark Y. Wahba
• X-ray rounds
• October 9th, 2003

2
Intussusception

• most common cause of intestinal obstruction
  between 3 mo and 6 yr of age
• 60 per cent of patients are younger than 1 yr
• 80 of the cases occur before 24 mo
• rare in neonates
• incidence 1-4/1,000 live births
• malefemale ratio is 41

3
Clinical Presentation

• sudden onset, in a previously well child, of
  severe paroxysmal colicky pain that recurs at
  frequent intervals and is accompanied by
  straining efforts with legs and knees flexed and
  loud cries
• Vomiting in most cases and is usually more
  frequent early
• In the later phase, the vomitus becomes bile
  stained
• Stools of normal appearance may occur during the
  first few hours of symptoms
• then fecal excretions are small or more often do
  not occur, and little or no flatus is passed

4
Clinical Presentation

• Blood generally is passed in the first 12 hr but
  at times not for 1-2 days and infrequently not at
  all
• 60 of infants pass a stool containing red blood
  and mucus, the currant jelly stool
• Some patients have only irritability and
  alternating or progressive lethargy
• Eventually a shock-like state may develop, with
  an elevation of body temperature to as high as
  41C (106F)

5
Clinical Presentation

• palpation usually reveals a slightly tender
  sausage-shaped mass
• often in the right upper quadrant
• about 30 of patients do not have a palpable mass
• presence of bloody mucus on the finger after DRE
  supports the diagnosis
• abdominal distention and tenderness develop as
  intestinal obstruction becomes more acute

6
Normal Abdomen

• 18 month old male

7
(No Transcript)
8
Case 1

• 2 month old female

9
(No Transcript)
10
Radiographic signs of Intussusception

• target sign
• crescent sign
• absent liver edge sign (also called absence of
  the subhepatic angle)
• bowel obstruction

11
Keep in mind

• plain abdominal films cannot be used to rule out
  intussusception

12
Target sign

• a mass in the right upper quadrant
• sometimes does not have a target appearance
• may just resemble a solid mass
• pseudokidney sign because it may have the shape
  of an oval mass in the RUQ

13
Crescent Sign

• caused by the intussuscepting lead point
  protruding into a gas filled pocket
• if the pocket is large, it may not be crescent
  shaped
• direction of the crescent always points in the
  direction of normal colon transit

14
Absent Liver Edge Sign

• Failure to see inferior edge of liver
• Caused by mass in RUQ
• Silhouetting of the liver edge

15
Bowel Obstruction

• gas distribution
• poor not much gas over most of the abdomen
• bowel dilation
• not a measured diameter of the bowel, but rather
  the loss of plications such that a smooth
  hose-like or sausage-like appearance results
• air-fluid levels
• classic candy cane (or upside down J) appearance
  where the level in one half of the loop is
  different from the level in the other half of the
  loop
• orderliness
• does view resembles a bag of sausages
  (obstruction) or a bag of popcorn (ileus)?

16
Back to Case 1

• 2 month old female

17
(No Transcript)
18
(No Transcript)
19
Case 2

• 3 year old female

20
(No Transcript)
21
(No Transcript)
22
Case 3

• 3 yr old male

23
(No Transcript)
24
(No Transcript)
25
Case 4

• 21 month old male

26
(No Transcript)
27
(No Transcript)
28
(No Transcript)
29
Case 5

• 8 month old male

30
(No Transcript)
31
(No Transcript)
32
(No Transcript)
33
Case 6

• 7 month old male

34
(No Transcript)
35
(No Transcript)
36
You think Intussusception, What next?

• Alert surgery that you are sending someone for
  imaging to rule out intussusception
• Get plain films
• If Hx, Phy and plain films convincing
• Air/Contrast Enema
• If Hx, Phy and plain films not completely
  convincing
• Ultrasound followed by Air/Contrast enema if
  necessary

37
Air/Contrast Enema

• diagnostic and therapeutic
• shows a filling defect in the head of contrast
  where its advance is obstructed by the
  intussusceptum
• contrast material between the intussusceptum and
  the intussuscipiens is responsible for the
  coil-spring appearance

38
Ultrasonography

• a sensitive diagnostic tool
• see a tubular mass in longitudinal views and a
  doughnut or target appearance in transverse images

39
Why Ultrasonography if Enema is diagnostic and
therapeutic?

• Fast (if operator available)
• No radiation
• Can rule in/out other pathology
• eg. appendicitis

40
Summary

• Radiographic signs of Intussusception
• target sign
• crescent sign
• absent liver edge sign (also called absence of
  the subhepatic angle)
• bowel obstruction
• May have a normal x-ray!

41
References

• Find the Intussusception Target and Crescent
  Signs Radiology Cases in Pediatric Emergency
  Medicine Volume 7, Case 18 Loren G. Yamamoto, MD,
  MPH University of Hawaii John A. Burns School of
  Medicine http//www.hawaii.edu/medicine/pediatrics
  /pemxray/v7c18.html
• Behrman Nelson Textbook of Pediatrics, 16th ed.,
  2000 W. B. Saunders Company
• Index of suspicion. Case 2. Diagnosis
  intussusception, Muhammad Waseem MD, Orlando
  Perales MD, Pediatrics in Review, Volume 22
  Number 4 April 2001
• James D'Agostino MD, COMMON ABDOMINAL EMERGENCIES
  IN CHILDREN Emergency Medicine Clinics of North
  America Volume 20 Number 1 February 2002 W.
  B. Saunders Company
• Dr. M. Hodsman
• Peter the radiiology resident and unknown
  Radiologist at Alberta Childrens Hospital

42
Extra slides

• From various sources

43
Intussusception

• cause of most intussusceptions is unknown
• seasonal incidence has peaks in spring and autumn
• correlation with adenovirus infections has been
  noted
• postulated that swollen Peyers patches in the
  ileum may stimulate intestinal peristalsis in an
  attempt to extrude the mass, thus causing an
  intussusception

44
Pathopysiology

• Intussusceptions are most often ileocolic and
  ileoileocolic, less commonly cecocolic, and
  rarely exclusively ileal
• Very rarely, the appendix forms the apex of an
  intussusception
• The upper portion of bowel, the intussusceptum,
  invaginates into the lower, the intussuscipiens,
  dragging its mesentery along with it into the
  enveloping loop.
• Constriction of the mesentery obstructs venous
  return engorgement of the intussusceptum
  follows, with edema, and bleeding from the mucosa
  leads to a bloody stool, sometimes containing
  mucus
• The apex of the intussusception may extend into
  the transverse, descending, or sigmoid
  colon--even to and through the anus in neglected
  cases. This presentation must be distinguished
  from rectal prolapse
• Most intussusceptions do not strangulate the
  bowel within the first 24 hr but may later
  eventuate in intestinal gangrene and shock

45
Clinical Presentation

• Intussusception should be considered strongly in
  the presence of a distinctive triad of factors
  vomiting without diarrhea colicky, intermittent
  abdominal pain and heme-positive stool. It is
  important to remember that only 20 of infants
  who have ileocolic intussusception have this
  typical triad.
• A definite anatomic lead point can be recognized
  in up to 10 of cases. Lead points are more
  common in neonates, older children, and adults
  than in infants between 5 and 24 months of age.
  The typical lead points include Meckel
  diverticulum, intestinal polyps, intestinal
  duplications, appendix, and neoplastic lesions.
  Lead points also occur more frequently in
  patients who have certain conditions, such as
  cystic fibrosis, Henoch-Schönlein purpura,
  Peutz-Jeghers syndrome, and hemolytic-uremic
  syndrome.
• Some children who have this condition become very
  still, listless, and pale and appear to be in
  shock due to the visceral pain. Lethargy may be
  the only presenting sign of intussusception in up
  to 10 of cases. The mechanism causing lethargy
  is unknown, although it is possible that
  endorphins or intestinal hormones resulting from
  the gastrointestinal insult are responsible.

46
Treatment

• Reduction of an acute intussusception is an
  emergency procedure and performed immediately
  after diagnosis in preparation for possible
  surgery
• In patients with prolonged intussusception with
  signs of shock, peritoneal irritation, intestinal
  perforation, or pneumatosis intestinalis,
  hydrostatic reduction should not be attempted
• success rate of hydrostatic reduction under
  fluoroscopic or ultrasonic guidance is
  approximately 50 if symptoms are present longer
  than 48 hr and 75-80 if reduction is done within
  the first 48 hr
• Bowel perforations occur in 0.5-2.5 of attempted
  barium reductions. The perforation rate with air
  reduction ranges from 0.1-0.2