Juxtaphrenic peak sign

The juxtaphrenic peak sign, also known as diaphragmatic tenting or Kattan sign, refers to the peaked or tented appearance of a hemidiaphragm which can occur in the setting of lobar collapse. It is caused by retraction of the lower end of diaphragm at an inferior accessory fissure (most common 1), major fissure or inferior pulmonary ligament. It is commonly seen in upper lobe collapse but may also be seen in middle lobe collapse.

History and etymology

It was first described by Kenneth R Kattan, an American radiologist, and his colleagues in 1980 6.

Chest x-ray
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Article information

rID: 18810
System: Chest
Section: Signs
Tag: stub, cases
Synonyms or Alternate Spellings:
  • Kattan's sign
  • Kattan sign
  • Juxtaphrenic peak
  • Juxta-phrenic peak sign
  • Juxtaphrenic peak (JP)
  • Diaphragmatic tenting
  • Tenting of the diaphragm

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Cases and figures

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    Luftsichel sign
    Case 1: in left upper collapse
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    Case 2 : on right
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    Case 3: on right with RUL collapse
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