Water-lily sign (hydatid cyst)

Dr Ian Bickle and A.Prof Frank Gaillard et al.

The water-lily sign is seen in hydatid infections when there is detachment of the endocyst membrane which results in floating membranes within the pericyst that mimic the appearance of a water lily.

It is classically described on plain radiographs (mainly chest X-ray) when the collapsed membranes are calcified but may be seen on ultrasound, CT and MRI.

Inspired signs
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Article information

rID: 2281
Section: Signs
Tag: lung
Synonyms or Alternate Spellings:
  • Water lilly sign
  • Waterlily sign
  • Water-lilly sign
  • Water lily

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Cases and figures

  •  Case 1: chest radiograph
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  • Case 1: CT
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  • Case 2: liver ultrasound
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  • Detachment of End...
    Case 3: liver ultrasound
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  • Cyst in the right...
    Case 4: liver ultrasound
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  • Case 5
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