Traumatic diaphragmatic hernia

Clinical:

  • A 45 years old man
  • Alleged involved in  motor vehicle accident
  • Complains of shortness of breath

Radiographic findings:

  • There is herniation of the stomach into left thoracic cavity (red arrow)
  • The left hemidiaphragm is not seen
  • There is shift to mediastinum and trachea (white arrow) to the right side
  • Presence of collar sign (yellow arrow)
  • Left lung shows compression effect
  • No pneumpthorax. No rib fracture.

Diagnosis: Traumatic diaphragmatic hernia

Discussion:

  • Traumatic diaphragmatic hernia often occur after a motor-vehicle collision. The estimated incidence ranges from 0.8-8% of patients who sustain blunt abdominal or lower thoracic trauma
  • Blunt diaphragmatic injuries with intrathoracic herniation of abdominal viscera carry a high mortality rate from 30 to 80%.
  • The herniation of the viscera through the rent in the diaphragm results in respiratory compromise. Visceral incarceration may occur with or without strangulation or perforation.
  • The left hemidiaphragm is involved three times more frequently than the right.
  • The most common site of rupture is the posterolateral aspect of the hemidiaphragm between the lumbar and intercostal muscle slips.
  • Ruptures occur radially and most are >10 cm in length 4. The most commonly herniated viscera are the stomach and colon.
    • inability to trace the normal hemidiaphragm contour
    • intrathoracic herniation of a hollow viscus
    • focal constriction of the viscus at the site of the tear (collar sign)
    • if large, the positive mass effect may cause a contralateral mediastinal shift
    • visualization of a nasogastric tube above the hemidiaphragm on the left side
    • left hemidiaphragm much higher than the rightSpecific diagnostic findings of diaphragmatic rupture on chest radiographs may not be seen in up to 50% of cases. However, the following signs are helpful in making the diagnosis
  • Many different modalities including conventional radiography, fluoroscopy, CT, and magnetic resonance imaging (MRI) have been used to evaluate the diaphragm;
  • Currently, multidetector CT (MDCT) is the modality of choice for detection of diaphragmatic injury with a sensitivity and specificity of 61-87% and 72-100%, respectively.
Author: radhianahassan