Sign Coiled Spring Sign

Etymology

  • The term “coiled spring sign” is derived from its visual similarity to a tightly coiled spring observed on radiological imaging.

AKA

  • Target sign (in some imaging modalities).

What is it?

  • A radiological sign indicative of intussusception, often observed on contrast-enhanced imaging studies such as barium fluoroscopy or CT scans.

Caused by:

  • Telescoping of one segment of the intestine into an adjacent segment (intussusception), typically at the ileocecal junction.

Most common causes:

  • Pediatric population: Idiopathic (most cases), often following viral infections.
  • Adult population: Secondary to pathologic lead points, such as tumors or polyps (5, 13).

Categories

Mechanical:

  • The primary category for intussusception, with lead points like polyps, tumors, or post-surgical adhesions causing telescoping (7).

Inflammation/Immune:

  • Conditions like Crohn’s disease can predispose to intussusception (11).

Neoplasm:

  • Gastrointestinal stromal tumors (GISTs) or adenocarcinomas can serve as lead points (5).

Inherited Congenital:

  • Associated syndromes like Peutz-Jeghers Syndrome due to hamartomatous polyps (4).

Idiopathic:

  • Particularly common in children, where no identifiable lead point exists (9).

Resulting in:

  • Partial or complete bowel obstruction, ischemia, and necrosis if untreated.

Structural changes:

  • Invaginated bowel loops with luminal narrowing and mesenteric compression.

Parts:

  • Most commonly involves the ileocecal region but can occur anywhere in the gastrointestinal tract.

Size:

  • Intussusception diameter varies, with larger masses more likely in cases involving lead points.

Shape:

  • Tubular or coiled appearance on imaging studies.

Position:

  • Most often in the right lower quadrant or central abdomen.

Character:

  • Alternating layers of bowel wall and mesentery, appearing as concentric rings.

Pathophysiology:

  • Invagination of the intestinal segment causes vascular compromise, leading to ischemia and potential necrosis.

Diagnosis:

  • Based on clinical symptoms like abdominal pain, vomiting, and palpable mass, combined with imaging findings (7, 10).

Clinical:

  • Children: Intermittent severe abdominal pain, bloody stool, and lethargy.
  • Adults: Symptoms more chronic, often linked to lead points like tumors.

Radiology:

X-Ray:

  • Findings: May show bowel obstruction with air-fluid levels.
  • Associated Findings: Target-like appearance with free air if perforation occurs (13).

X-ray/Fluoroscopy (Barium Studies):

  • Findings: Coiled spring sign, reflecting contrast trapped between intussuscepted bowel loops.
  • Associated Findings: Tapered “beak sign” at the lead point (1, 7).

CT:

  • Findings: Target sign or sausage-shaped mass with mesenteric fat and vessels at the center.
  • Associated Findings: Bowel wall thickening, obstruction, or ischemic changes (9, 10).

MRI:

  • Findings: High-resolution imaging shows layered appearance of the intussusception, best for soft tissue differentiation.
  • Associated Findings: Hyperintense regions on T2-weighted imaging in areas of edema (8).

US:

  • Findings: Target or doughnut sign in cross-section; pseudokidney sign in longitudinal view.
  • Associated Findings: Reduced blood flow on Doppler if ischemia is present (9).

Other Relevant Imaging Modalities:

PET/CT:

  • Findings: Useful in identifying underlying malignancy but not routine for intussusception (5).

Angiography:

  • Rarely used, but can identify vascular compromise in complicated cases.

Other Diagnostic Procedures:

  • Labs: Non-specific; anemia and leukocytosis may be present in advanced cases.

Differential Diagnosis:

  • Most common: Adhesions, malignancies, or inflammatory bowel disease.
  • Other categories:
    • Infection: Viral enteritis mimicking symptoms.
    • Neoplasm: GIST, lymphoma, or adenocarcinoma (5).

Recommendations:

  • Immediate management for acute intussusception includes hydrostatic or air enema in children and surgical intervention in adults (7).
  • Surveillance in syndromic cases (e.g., PJS) to prevent complications (4).

Key Points and Pearls:

  • The coiled spring sign is a hallmark of intussusception seen on fluoroscopic studies.
  • Early imaging is crucial to prevent ischemic complications.
  • CT and MRI are invaluable for identifying underlying causes, especially in adults with lead points (5, 8).

References

  1. Clinics in Diagnostic Imaging. 159. Jejunal Intussusception Due to Peutz-Jeghers Syndrome Krishnan V, Chawla A, Wee E, Peh WC
    Singapore Medical Journal. 2015;56(2):81-5; quiz 86.
  2. Update on Imaging of Peutz-Jeghers Syndrome Tomas C, Soyer P, Dohan A, et al.
    World Journal of Gastroenterology. 2014;20(31):10864-75.
  3. Diagnosis and Management of Cancer Risk in the Gastrointestinal Hamartomatous Polyposis Syndromes: Recommendations From the US Multi-Society Task Force on Colorectal Cancer
    Boland CR, Idos GE, Durno C, et al.
    Gastroenterology. 2022;162(7):2063-2085.
  4. Peutz-Jeghers Syndrome McGarrity TJ, Amos CI, Baker MJ
    GeneReviews® [Internet]. Updated 2021 Sep 2.
  5. Peutz-Jeghers Syndrome and the Role of Imaging: Pathophysiology, Diagnosis, and Associated Cancers
    Klimkowski S, Ibrahim M, Ibarra Rovira JJ, et al.
    Cancers. 2021;13(20):5121.
  6. Adult Intussusception: Demonstration by Current MR Techniques
    Marcos HB, Semelka RC, Worawattanakul S
    Magnetic Resonance Imaging. 1997;15(9):1095-8.
  7. Clinical Presentations and Surgical Approach of Acute Intussusception Caused by Peutz-Jeghers Syndrome in Adults Wang H, Luo T, Liu WQ, et al. Journal of Gastrointestinal Surgery. 2011;15(12):2218-25.
  8. Comparative Effectiveness of Imaging Modalities for the Diagnosis and Treatment of Intussusception: A Critically Appraised Topic Carroll AG, Kavanagh RG, Ni Leidhin C, et al.
    Academic Radiology. 2017;24(5):521-529.
  9. Accuracy of Point-of-Care Ultrasound and Radiology-Performed Ultrasound for Intussusception: A Systematic Review and Meta-Analysis Tsou PY, Wang YH, Ma YK, et al.
    The American Journal of Emergency Medicine. 2019;37(9):1760-1769.
  10. Chronic Intussusception in Childhood Schulman H, Laufer L, Kurzbert E, Cohen Z, Hertzanu Y
    European Radiology. 1998;8(8):1455-6.
  11. MRI of the Small-Bowel: How to Differentiate Primary Neoplasms and Mimickers Masselli G, Colaiacomo MC, Marcelli G, et al.
    The British Journal of Radiology. 2012;85(1014):824-37.
  12. Multidetector Computed Tomography Diagnosis of Small Bowel Intussusceptions in Adults: Observations in a 10-Year Single-Center Study Hu M, Long F, Long W, et al.
    Acta Radiologica. 2021;62(12):1567-1574.
  13. Clinical Characteristics of Intussusception Secondary to Pathologic Lead Points in Children: A Single-Center Experience With 65 Cases Lin XK, Xia QZ, Huang XZ, et al.
    Pediatric Surgery International. 2017;33(7):793-797.
  14. Colonic Intussusception: Clinical and Radiographic Features
    Gollub MJ AJR. American Journal of Roentgenology. 2011;196(5):W580-5.

 

  1. Clinics in Diagnostic Imaging. 159. Jejunal Intussusception Due to Peutz-Jeghers Syndrome
    Krishnan V, Chawla A, Wee E, Peh WC
    Singapore Medical Journal. 2015;56(2):81-5; quiz 86.
  2. Update on Imaging of Peutz-Jeghers Syndrome
    Tomas C, Soyer P, Dohan A, et al.
    World Journal of Gastroenterology. 2014;20(31):10864-75.
  3. Peutz-Jeghers Syndrome and the Role of Imaging: Pathophysiology, Diagnosis, and Associated Cancers
    Klimkowski S, Ibrahim M, Ibarra Rovira JJ, et al.
    Cancers. 2021;13(20):5121.
  4. Adult Intussusception: Demonstration by Current MR Techniques
    Marcos HB, Semelka RC, Worawattanakul S
    Magnetic Resonance Imaging. 1997;15(9):1095-8.
  5. Comparative Effectiveness of Imaging Modalities for the Diagnosis and Treatment of Intussusception: A Critically Appraised Topic
    Carroll AG, Kavanagh RG, Ni Leidhin C, et al.
    Academic Radiology. 2017;24(5):521-529.
  6. Accuracy of Point-of-Care Ultrasound and Radiology-Performed Ultrasound for Intussusception: A Systematic Review and Meta-Analysis
    Tsou PY, Wang YH, Ma YK, et al.
    The American Journal of Emergency Medicine. 2019;37(9):1760-1769.
  7. Chronic Intussusception in Childhood
    Schulman H, Laufer L, Kurzbert E, Cohen Z, Hertzanu Y
    European Radiology. 1998;8(8):1455-6.
  8. MRI of the Small-Bowel: How to Differentiate Primary Neoplasms and Mimickers
    Masselli G, Colaiacomo MC, Marcelli G, et al.
    The British Journal of Radiology. 2012;85(1014):824-37.
  9. Multidetector Computed Tomography Diagnosis of Small Bowel Intussusceptions in Adults: Observations in a 10-Year Single-Center Study
    Hu M, Long F, Long W, et al.
    Acta Radiologica. 2021;62(12):1567-1574.
  10. Colonic Intussusception: Clinical and Radiographic Features
    Gollub MJ
    AJR. American Journal of Roentgenology. 2011;196(5):W580-5.

Clinical

  1. Diagnosis and Management of Cancer Risk in the Gastrointestinal Hamartomatous Polyposis Syndromes: Recommendations From the US Multi-Society Task Force on Colorectal Cancer
    Boland CR, Idos GE, Durno C, et al.
    Gastroenterology. 2022;162(7):2063-2085.
  2. Peutz-Jeghers Syndrome
    McGarrity TJ, Amos CI, Baker MJ
    GeneReviews® [Internet]. Updated 2021 Sep 2.
  3. Clinical Presentations and Surgical Approach of Acute Intussusception Caused by Peutz-Jeghers Syndrome in Adults
    Wang H, Luo T, Liu WQ, et al.
    Journal of Gastrointestinal Surgery. 2011;15(12):2218-25.
  4. Clinical Characteristics of Intussusception Secondary to Pathologic Lead Points in Children: A Single-Center Experience With 65 Cases
    Lin XK, Xia QZ, Huang XZ, et al.
    Pediatric Surgery International. 2017;33(7):793-797.