intussusception: a guide to diagnosis and intervention in children
TRANSCRIPT
Intussusception: A Guide to Diagnosis and Intervention in Children
Genevieve Daftary, Harvard Medical School,
Year IIIGillian Lieberman, MD
Genevieve Daftary, MS3Gillian Lieberman, MD
November 2005
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The Anatomy of Intussusception
Intussusception occurs when a segment of bowel, the intussusceptum, telescopes into a more distant segment of bowel, the intussuscipiens
The most common type is ileocolic (pictured here), followed by ileoileocolic, ileoileas, and colocolic
Radiologic Clinics of North America 1997
www.yoursurgery/Intussusception.jpg
Intussuscipiens
Genevieve Daftary, MS3Gillian Lieberman, MD
November 2005
Radiologic Clinics of North America 1997; Pediatrics 20003
Demographics
Most common acute abdominal disorder of early childhood (56 children/ 100,000/ year in US)
Boys 4x’s more frequently than girls
Majority of patients between 3 mon and 3 yr– Peak incidence between 5 and 9 months– 75% under 2 years
Seasonal peaks in spring and autumn
95% no pathologic lead point
5-10% recognizable lead point
Some evidence of significant attributable risk with rotavirus vaccine administration
Genevieve Daftary, MS3Gillian Lieberman, MD
November 2005
Radiologic Clinics of North America 1996,19974
Etiologies of Intussusception
Idiopathic: no defined lead point– Association with viral illness (adenovirus)– Hypertrophy of lymphoid tissue
Recognizable cause for lead point– Meckel’s diverticulum– Intestinal polyp– Enteric duplication– Lymphoma– Intramural hematoma– Ameboma– Henoch-Schönlein purpura
Genevieve Daftary, MS3Gillian Lieberman, MD
November 2005
Radiologic Clinics of North America 1996, 19975
Clinical Presentation: VARIABLE
Intermittent, colicky cramping, pain
Later development of lethargy and somnolence
Vomiting (may be bile-stained)
Current jelly stool (blood and mucus)
Sausage shaped mass
Distention and tendernessClassic Triad: abdominal pain, currant jelly stool,
palpable abdominal mass (<50%)
Genevieve Daftary, MS3Gillian Lieberman, MD
November 2005
Radiologic Clinics of North America 19976
Complications
Typically do not occur within the first 24 hrs…
Bowel obstruction
Intestinal ischemia
Perforation
Shock
Sepsis
Dehydration…thus we have a window of opportunity in which
to treat and avoid surgery.
Genevieve Daftary, MS3Gillian Lieberman, MD
November 2005
AJR 2005; Rad Clinics of N Amer 19967
Overview of Screening Tools
Abdominal Radiograph– Screen for other Dx’s and free air– Can be safely omitted in the presence of US– 45% sensitivity
Abdominal Sonography– Diagnostic accuracy near 100%, eval of reducibility, +/- lead
point, post reduction, ischemia
Abdominal CT scan– Accuracy approaching 100%; especially good for lead points– High cost, risk of radiation, and risk of sedation in children
make it unpractical
Genevieve Daftary, MS3Gillian Lieberman, MD
November 2005
Children's Hospital Boston8
Patient One: Presentation
6 year old female
3 weeks ago: URI w/ fever, vomiting, diarrhea (greenish, non-bloody), abdominal pain; seemed to resolve after 3 days
1 week ago: increasingly lethargic and irritable, w/vomiting and fever
Genevieve Daftary, MS3Gillian Lieberman, MD
November 2005
Children's Hospital Boston9
Patient One: Supine KUB
Genevieve Daftary, MS3Gillian Lieberman, MD
November 2005
Children's Hospital Boston10
Patient One: Supine KUB
Paucity of Gas on Right Side of Abdomen
Genevieve Daftary, MS3Gillian Lieberman, MD
November 2005
Radilogic Clinics of North America 1996; Amer J Rad 200511
Abdominal Radiograph
Signs of Intussusception– Soft tissue mass– Target sign: created by mesenteric fat– Absence of cecal gas and stool– Meniscus sign: crescent of gas outlining intussusceptum– Loss of visualization of the tip of the liver– Paucity of bowel gas
Poor sensitivity for dx of intussusception: 45%
May be useful to exclude other Dx
Determine presence of free air (contraindication to non- surgical reduction with contrast)
May be safely omitted if ultrasound is available
Genevieve Daftary, MS3Gillian Lieberman, MD
November 2005
RadioGraphics 199912
Target & Meniscus Signs
Genevieve Daftary, MS3Gillian Lieberman, MD
November 2005
RadioGraphics 199913
Target & Meniscus Signs
Genevieve Daftary, MS3Gillian Lieberman, MD
November 2005
Children's Hospital Boston14
Patient One: Longitudinal Ultrasound
Genevieve Daftary, MS3Gillian Lieberman, MD
November 2005
Children's Hospital Boston15
Patient One: Longitudinal Ultrasound
•Telescoping Bowel
•Sandwich Sign/ Pseudokidney
Genevieve Daftary, MS3Gillian Lieberman, MD
November 2005
Children's Hospital Boston16
Patient One: Axial Ultrasound
Genevieve Daftary, MS3Gillian Lieberman, MD
November 2005
Children's Hospital Boston17
Patient One: Axial Ultrasound
Doughnut/ Target Sign
Genevieve Daftary, MS3Gillian Lieberman, MD
November 2005
Children's Hospital Boston18
Patient One: Doppler Ultrasound
Genevieve Daftary, MS3Gillian Lieberman, MD
November 2005
Children's Hospital Boston19
Patient One: Doppler Ultrasound
•Blood flow maintained
•Rule out ischemia of involved bowel
Genevieve Daftary, MS3Gillian Lieberman, MD
November 2005
Rad Clinics of N Amer 199720
Abdominal Ultrasound
Replaced abdominal radiograph as primary screening modality
Sensitivity 98 -100%; specificity 88 -100%
Appearance: outer hypoechoic region surrounding an echogenic center or multiple concentric rings
Use Doppler to determine bowel ischemia; guides reduction decisions
Guide hydrostatic and pneumatic reduction
Genevieve Daftary, MS3Gillian Lieberman, MD
November 2005
RadioGraphics 199921
Ultrasound Cross-Sections
• A = intussuscipiens
• B = everted intussusceptum
• C = central intussusceptum
• M = mesentery
• L = lymph nodes
• MS = contacting mucosal surfaces
• S = contacting serosal surfaces
Genevieve Daftary, MS3Gillian Lieberman, MD
November 2005
Children's Hospital Boston22
Patient One: Air Enema
Normal bowel gas pattern: Spontaneous Reduction
Genevieve Daftary, MS3Gillian Lieberman, MD
November 2005
RadioGraphics 199923
Enemas
Air, Liquid (saline, soluble contrast), Barium
At one time used for Dx– Coiled spring: edematous mucosal folds of returning
intussusceptum outlined by contrast in colon– Meniscus sign
Now used mainly for Treatment/Reduction– Avoid patient discomfort and risk of perforation– US better diagnostic tool & rule out tool
Genevieve Daftary, MS3Gillian Lieberman, MD
November 2005
RadioGraphics 199924
Meniscus & Coiled Spring Signs
Genevieve Daftary, MS3Gillian Lieberman, MD
November 2005
Radiology 2001; AJR 2004 & 2005; Rad Clinics of N Amer 199625
Reduction Procedures
Barium enema: previous standard for Dx and reduction– Risk of barium peritonitis, infection, adhesions,
radiation exposure with fluoroscopy, only see lumen– 55-95% accuracy– Iodinated contrast safer but causes fluid shifts
US-guided Hydrostatic reduction– No radiation, good visualization of intussusception &
lead points– Need sonographer
Genevieve Daftary, MS3Gillian Lieberman, MD
November 2005
Radiology 2001; AJR 2004 & 2005; RadioGraphics 199926
Reduction Procedures cont.
Pneumatic reduction with fluoroscopic guidance– Quick, safe, clean (less fecal spillage), cheap– Radiation exposure, cannot depict lead points well, only see
intraluminal content
US-guided Pneumatic reduction– No radiation, confirm dx, highest successful reduction rate
(92%), quick and clean, can see lead points well (but not all)– Air blocks US beam; difficult to see ileocecal valve and
residual intussusceptions
Surgical
Genevieve Daftary, MS3Gillian Lieberman, MD
November 2005
Rad Clinics of N Amer 199627
Contraindications to Enema
Dehydration
Peritonitis
Shock
Sepsis
Free air on radiographStabilize then treat surgically
Genevieve Daftary, MS3Gillian Lieberman, MD
November 2005
AJR 200528
Complications of Reduction
Perforation– Overall rate of 0.8%– Similar rates for liquid and air enemas– Perforations with air usually smaller
Recurrence– Approximately 10%– Similar rates for liquid and air enemas– 50% will occur within 48 hrs– Repeat enemas are safe and effective
Genevieve Daftary, MS3Gillian Lieberman, MD
November 2005
AJR 200529
Reduction Guidelines
Liquid Enema Rule of Three’s for Barium– 3 attempts– 3 min duration– Liquid enema bag 3 feet above fluoroscopy table (5
feet if using water-soluble contrast)
Air Enema– Ensure maximal pressures <120 mm Hg at rest
Genevieve Daftary, MS3Gillian Lieberman, MD
November 2005
AJR 2002 & 200530
Success of Reduction Depend On…
Short duration of symptoms (<24-48 hrs)
Adequate hydration
Age (older than 3 months)
Absence of small-bowel obstruction
Absence of trapped intraperitoneal fluid
Absence of enlarged lymph nodes in the intussusceptum
Adequate blood flow
Location other than the rectum (rectum only 25% success)
Genevieve Daftary, MS3Gillian Lieberman, MD
November 2005
Children's Hospital Boston31
Patient Two: Presentation
2 year old male
Worsening vomiting and abdominal pain since the morning of admission
Vomited 8x’s since morning, no bile, blood or stool
No fevers; no current or recent illness
No new foods, travel or trauma
Prior incident of vomiting which he recovered from one month prior
Abdomen soft, non-distended with active BS, diffusely tender
Genevieve Daftary, MS3Gillian Lieberman, MD
November 2005
Children's Hospital Boston32
Patient Two: Supine KUB
Patient does not have classic triad of intussusception
Use KUB to consider other diagnoses
Genevieve Daftary, MS3Gillian Lieberman, MD
November 2005
Children's Hospital Boston33
Patient Two: Supine KUB
•Paucity of Gas on Right
•Dilated loops of small bowel
•Looks like obstruction
Genevieve Daftary, MS3Gillian Lieberman, MD
November 2005
Felson, Gamuts in Radiology34
DDx of Intestinal Obstruction in a Child
Adhesions/Congenital peritoneal bands (Ladd’s bands
Appendicitis
Hernia, incarcerated (internal or external)
Hirschsprung disease
IntussusceptionUncommonly: Crohn’s, fecal impaction, bezoar,
Kawasaki , neoplasm, congenital stenosis, TB, volvulus, CF, Chronic granulomatous disease
Genevieve Daftary, MS3Gillian Lieberman, MD
November 2005
Children's Hospital Boston35
Patient Two: Longitudinal Ultrasound
Use US to explore possible causes of obstruction including intussusception
Patient is not exposed to any further radiation or the discomfort of enema until further Dx
Genevieve Daftary, MS3Gillian Lieberman, MD
November 2005
Children's Hospital Boston36
Patient Two: Sagittal Ultrasound
Dilated loops of bowel
Genevieve Daftary, MS3Gillian Lieberman, MD
November 2005
Children's Hospital Boston37
Patient Two: Axial Ultrasound
Genevieve Daftary, MS3Gillian Lieberman, MD
November 2005
Children's Hospital Boston38
Patient Two: Axial Ultrasound
•Doughnut/Target Sign
•Patient’s obstruction is due to intussusception
Genevieve Daftary, MS3Gillian Lieberman, MD
November 2005
Children's Hospital Boston39
Patient Two: Doppler Ultrasound
Genevieve Daftary, MS3Gillian Lieberman, MD
November 2005
Children's Hospital Boston40
Patient Two: Doppler Ultrasound
•Blood flow maintained
•Rule out bowel ischemia
•Patient is safe to receive an US guided air enema with likelihood of resolution
Genevieve Daftary, MS3Gillian Lieberman, MD
November 2005
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Review
Intussusception is COMMON in young children
Clinical presentation is variable underscoring the need for a safe, quick, inexpensive screening tool such as ultrasound
Ultrasound is extremely accurate in diagnosing obstruction; CT is more accurate in defining a lead point; abdominal radiographs can be helpful in considering other diagnoses
Ultrasound guided air enema combines the safety of ultrasound (lack of radiation) with the effectiveness, ease, cleanliness, and safety of air enema in reducing intussusception
Genevieve Daftary, MS3Gillian Lieberman, MD
November 2005
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What does intussusception look like on CT?
Since lead points are more likely in the adult population, CT is done more frequently in this population with suspected intussusception
Scroll through the following images to get a sense of what intussusception looks like on CT
Notice the familiar target sign, also useful in diagnosis using plain film and ultrasound!
Genevieve Daftary, MS3Gillian Lieberman, MD
November 2005
BIDMC PACS43
Intussusception on CT
Genevieve Daftary, MS3Gillian Lieberman, MD
November 2005
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Intussusception on CT
Genevieve Daftary, MS3Gillian Lieberman, MD
November 2005
BIDMC PACS45
Intussusception on CT
Genevieve Daftary, MS3Gillian Lieberman, MD
November 2005
BIDMC PACS46
Intussusception on CT
Genevieve Daftary, MS3Gillian Lieberman, MD
November 2005
BIDMC PACS47
Intussusception on CT
Genevieve Daftary, MS3Gillian Lieberman, MD
November 2005
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Intussusception on CT
Genevieve Daftary, MS3Gillian Lieberman, MD
November 2005
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References
Applegate KE. Clinically Suspected Intussusception in Children: Evidence-Based Review and Self-Assessment Module. AJR 2005; 185: S175-S183.
Daneman A and Alton J. Intussusception: Issues and Controversies Related to Diagnosis and Reduction. Radiologic Clinics of North America 1996; 34: 743-756.
Del-Pozo G et al. Intussusception in Children: Current Concepts in Diagnosis and Enema Reduction. RadioGraphics 1999; 19: 299-319.
Felson. Gamuts in Radiology.
Koumanicou C et al. Sonographic Detection of Lymph Nodes in the Intussusception of Infants and Young Children. AJR 2002; 178: 445-450.
Navarro O, Daneman A, Chae A. Intussusception: The Use of Delayed Repeated Reduction Attempts and the Management of Intussusceptions Due to Pathologic Lead Points in Pediatric Patients. AJR 2004; 182: 1169-1176.
Parashar UD et al. Trends in Intussusception-Associated Hospitalizations and deaths Among US Infants. Pediatrics 2000; 106: 1413-1421.
Sivit CJ. Gastrointestinal Emergencies in Older Infants and Children. Radiologic Clinics of North America 1997; 35: 865-877.
Yoon CH, Kim HJ, Goo HW. Intussusception in Children: US-guided Pneumatic Reduction—Initial Experience. Radiology 2001; 218: 85-88.
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Acknowledgements
Special Thanks To…– Melissa Gerlach, MD– Anne-Catherine Kim, MD– Larry Barbaras, Webmaster– Pamela Lepkowski– Gillian Lieberman, MD