Bochdalek hernia

A Bochdalek hernia is a form of congenital diaphragmatic hernia. They occur posteriorly and are due to a defect in the posterior attachment of the diaphragm when there is a failure of pleuroperitoneal membrane closure in utero. Retroperitoneal structures may prolapse through the defect, e.g. retroperitoneal fat, spleen or left kidney.

Clinical presentation

Large hernias typically present in infancy, are usually are said to be most frequently left sided, presumably owing to the protective effects of the liver, although recently this has been disputed, at least in adults 1. The left opening of the posterior diaphragm closes later in fetal life than the right which may also contribute to the asymmetric occurence. Complications are usually due to pulmonary hypoplasia.

In adults, incidentally-discovered posterior diaphragmatic hernias are rare (0.17% of patients having an abdominal CT). Of these, right-sided hernias are more common (68%), and more frequent in females. The great majority are small, with only 27% containing abdominal organs such as bowel, spleen or liver.

Radiographic features

Plain radiograph

On conventional radiographs, the hernia may appear as a lung base soft-tissue opacity lesion seen posteriorly on lateral images.


CT usually demonstrates fat above the diaphragm and is extremely beneficial in revealing organ entrapment. Coronal and sagittal reformatted images show the defect to best advantage.

Differential diagnosis

  • Bochdalek herniae may mimic diaphragmatic rupture from trauma, but you would expect to find other supportive signs of chest and/or abdominal trauma.


BBBBB is a simple mnemonic to recall the features of Bochdalek hernias.

See also

Edit Article Share Article

Article Information

rID: 1001
Synonyms or Alternate Spellings:
  • Bochdalek herniation
  • Bochdalek's herniation
  • Bochdalek's hernia
  • Drag
    Case 1
    Drag here to reorder.
  • Drag
    Case 2
    Drag here to reorder.
  • Drag
    Iniencephaly with...
    Case 4: with concurrent pregnancy with iniencephaly
    Drag here to reorder.
  • Drag
    Case 5
    Drag here to reorder.
  • Updating… Please wait.


    Error Unable to process the form. Check for errors and try again.

    Alert_accept Thank you for updating your details.