MyPACS.net: Radiology Teaching Files > Case 40200015

Last visited 04-27-2010 INTUSSUSCEPTION
Contributed by: Faculty and residents Children's Hospital, Radiologist, Children's Health System, Birmingham, Alabama., USA.
Patient: 4 month old male
History: 4 month old male with hematochezia.
Images:[small]larger

Fig. 1: RUQ ultrasound

Fig. 2: RUQ ultrasound

Fig. 3: Barium Enema

Fig. 4: Barium Enema

Fig. 5: Barium Enema
Findings:

Ultrasound shows an elongate mass in the right upper quadrant.   Transverse images of the mass demonstrate a swirled appearance of alternating sonolucent and hyperechoic regions of presumed bowel wall typical of the loop-within-a-loop appearance of Intussusception.  Longitudinal images of the mass demonstrate linear areas alternating sonolucent and hyperechoic regions of presumed bowel wall typical of the loop-within-a-loop appearance of Intussusception. "submarine sandwich sign"

Barium enema demonstrates a mass in the ascending colon and cecum which reduces with insufflation of air.

 

 

Diagnosis: Intussusception
Discussion:

Demographics

In infants aged 6 months to 2 years, intussusception is not unusual and often follows an upper respiratory tract illness; however, inciting factors may be absent.  The male-to-female ratio of intussusception is 3:1-2.

Presentation

Most intussusceptions are acute. The clinical picture is of a well-nourished infant with the following signs and symptoms of bowel obstruction:

  • Cramping abdominal pain
  • Poor feeding
  • Vomiting

The infant usually has one or more episodes of diarrhea mixed with blood and mucus (ie, currant-jelly stool), which is related to venous congestion. A palpable, slightly tender, sausage-shaped mass in the abdomen is characteristic. Although usually acute, chronic or recurrent intussusception may occur, with typical symptoms. In some patients, intussusception is painless; the infant may appear pale, diaphoretic, or lethargic. The physician may not suspect intussusception if unusual symptoms are present or if symptoms mask an upper respiratory infection. 

Pathophysiology

Invagination of a bowel segment (usually, the small bowel) into the lumen of the more distal bowel (usually, the colon) occurs. The invaginated segment (intussusceptum) is carried distally by peristalsis. Mesentery and vessels become involved with the intraluminal loop and are squeezed within the engulfing segment (intussuscipiens). Almost all occurrences are acute. Venous congestion is a major factor both in symptomatology and in the characteristic presence of blood in the stool.

Recent illness may create a lead point for intussusception due to lymphoid hyperplasia.  Intussusception is known to occur with greater frequency in children who have undergone recent abdominal surgery, either intraperitoneal or retroperitoneal operations. It is thought that early adhesions or focal edema of the bowel wall create a lead point for the intussusception. Children with postoperative intussusception may present with unexplained bowel obstruction within a time frame that is unusual for the development of bowel obstruction in postoperative patients.  

Additional lead points in nonidiopathic intussusception may include the following:

  • Meckel diverticulum
  • Lymphoma of bowel
  • Leukemia involving bowel
  • Henoch-Schönlein purpura with intramural hemorrhage
  • Hemolytic uremic syndrome
  • Cystic fibrosis with inspissated bowel content
  • Postoperative complication following retroperitoneal surgery
  • Post abdominal trauma
  • Inflammatory bowel disease
  • Polyp
  • Peutz-Jeghers syndrome appendix (normal or appendicitis)
  • Recent rotavirus immunization

Preferred Examination

In some countries, history and physical findings are sufficient criteria for undertaking reduction procedures for intussusception.

  • Abdominal radiograph: A search should be made for dilated small bowel and an absence of gas in the region of the cecum.  In some cases, a mass impression within the colonic gas indicates an intraluminal mass created by the intussuscepting loop.
  • Ultrasound
    • Transverse: Ultrasound (US) shows a mass with a swirled appearance of alternating sonolucent and hyperechoic bowel wall of the loop-within-a-loop.
    • Longitudinal: On US, the intussuscipiens and the intussusceptum have the appearance of a submarine sandwich. There appear to be multiple layers, which represent the walls of the intussuscepted bowel loops. 
    • In some institutions, reduction of the intussusception takes place under US guidance with fluid or air.

Once the patient is stabilized, reduction procedures should be initiated immediately; radiographic examination and physical examination should be performed to ensure that neither free air nor peritonitis is present. It should be ascertained by physical examination that no peritonitis is present. Spontaneous reduction has been reported, but it is unusual.

Surgical consultation should be sought early when intussusception is suspected. Despite positive results from reduction through the use of imaging techniques, reduction or re-intussusception may be unsuccessful, necessitating surgery. Surgeons should be made aware of the possible need for surgery. Rarely, complications from reduction with imaging techniques (perforation) require emergency surgery. Thus, alerting the surgical consultant is a prudent measure. The use of air, gas, or water-soluble contrast to reduce the intussusception decreases potential complications.

Intervention

Unless perforation, peritonitis, or Henoch-Schönlein purpura is present, radiologic reduction should be attempted. The success rate is 50-85%, depending on factors such as the length of time of the intussusception and degree of edema of the loop and ileocecal valve. Reduction is still possible, although more difficult, in intussusceptions that have been in place for longer than 48 hours. In patients older than 2 years, it should be assumed that intussusception has a lead point etiology; in such cases, further investigation should be undertaken.

Air reduction

In the current method of air reduction, room air is introduced through a rectal catheter and is taped well in place. A manometer is attached to a Y-connector to monitor pressure in the colon. Pressure should never exceed 110 mm Hg. The air pressure on the intussusception usually forces the inverted bowel back through the ileocecal valve and into its proper position. When reduction occurs, the observed pressure falls precipitously.

Contrast reduction

Contrast reduction was widely used until the current decade. A large rectal tube is taped firmly in place, and dilute water-soluble contrast is introduced slowly by gravity drip into the rectum; hydrostatic pressure is used to reduce the intussusception. The fluid is placed a maximum of 3 feet above the level of the radiography table. No more than 3 attempts at reduction are undertaken, and the column is pressed against the intussusception mass no longer than 3 minutes at each attempt. Visualization of the small bowel usually indicates that intussusception has been reduced. The following rules need to be observed:

  • The fluid level should be maintained at no more than 3 feet above the patient.
  • Palpation of the abdomen should be avoided during reduction.
  • Pressure should be maintained no longer than 3 minutes against a nonmoving intussusception.

Recurrences

Intussusception recurs in approximately 10% of children.  Intussusception can recur at any time and is not a contraindication to repeat reduction. Sedation to assist reduction does not greatly affect the reduction rate. Glucagon has been advocated, but its efficacy has not been established.

Medicolegal Pitfalls

  • Failure to make the diagnosis in a timely manner is a pitfall. In subtle or unsuspected occurrences of intussusception, delay in the diagnosis may allow the condition to progress to bowel infarction and bowel perforation. Thus, awareness of the possible diagnosis is important in a young patient with any of the symptoms or signs of intussusception, even when they are not characteristic.

 

References: Emedicine
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Additional Details:

Case Number: 40200015Last Updated: 04-27-2010
Anatomy: Gastrointestinal (GI)   Pathology: Benign Mass, Cyst
Modality: GIAccess Level: Readable by all users
Keywords: intussusception

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