Diaphragmatic eventration refers to an abnormal contour of the diaphragmatic dome. It typically affects only a segment of the hemidiaphragm, compared to paralysis/weakness where the entire hemidiaphragm is typically affected.
Diaphragmatic eventration is congenital in nature and due to incomplete muscularisation of the diaphragm with a thin membranous sheet replacing normal diaphragmatic muscle. Over time this region stretches and on inspiration does not contract normally.
Frequently eventration is seen in the a anteromedial portion of the right hemidiaphragm.
Elevation of the affected portion of the diaphragm is usually seen as a smooth hump, while the remainder of the hemidiaphragm contour is normal. The frontal X-ray may show a 'double' diaphragmatic contour, which is easily confirmed on the lateral projection.
- may be a sharp border between eventrated portion and the remainder of the hemidiaphragm 4
Possible consderations on plain film includes
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