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The hourglass sign.

Aina Venkatasamy1, Tri Thai Huynh2, Bénédicte Caron3

  • 1Service de Radiologie 1, Hôpitaux Universitaires de Strasbourg, 1 avenue Molière, Strasbourg, France. aina.venkatasamy@chru-strasbourg.fr.

Abdominal Radiology (New York)
|September 23, 2017
PubMed
Summary
This summary is machine-generated.

The Hourglass sign, also known as the Collar sign, is a key indicator for diagnosing diaphragmatic rupture with herniated viscera on CT scans. This imaging finding offers high specificity for detecting this serious condition.

Keywords:
CTCollar signDiaphragmatic ruptureHourglass sign

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Area of Science:

  • Radiology
  • Medical Imaging
  • Surgical Anatomy

Background:

  • Diaphragmatic rupture with viscera herniation is a critical condition requiring accurate diagnosis.
  • Multidetector computed tomography (MDCT) is a primary imaging modality for evaluating blunt abdominal trauma.
  • Identifying specific imaging signs can improve diagnostic accuracy and patient outcomes.

Purpose of the Study:

  • To highlight the diagnostic utility of the Hourglass sign in identifying diaphragmatic ruptures with viscera herniation on MDCT.
  • To provide a comprehensive overview of the Hourglass sign, including its alternative name and historical description.

Main Methods:

  • Review of medical literature for studies describing the Hourglass sign (or Collar sign).
  • Analysis of reported sensitivity and specificity of the Hourglass sign on MDCT for diaphragmatic rupture.
  • Description of the anatomical basis of the sign.

Main Results:

  • The Hourglass sign demonstrates high specificity (98%-100%) for diagnosing diaphragmatic rupture with viscera herniation.
  • Sensitivity ranges from 16% to 63%, indicating it is a valuable but not universally present sign.
  • The sign is characterized by a waistlike constriction of herniated viscera at the diaphragmatic defect.

Conclusions:

  • The Hourglass sign is a reliable imaging clue for diagnosing diaphragmatic ruptures on MDCT.
  • Recognition of this sign, also termed the Collar sign, aids in the prompt identification of herniated abdominal contents through the diaphragm.