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Medical AI Inquiry: You were designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.
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Water lily appearance in chest X-ray suggestive of:
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The correct answer is  Hydatid cyst is caused by the parasite echinococcus granulosus. It is often associated with hydatid cyst of liver.It is usually single buy multiple hydatis cysts can occur. In chest X-ray a dense homogenous opacity can be seen. A collapsed laminated membrane produces an irregular projections in a fluid level due to rupture of the cyst which shows a characteristic 'water lily' appearance on chest X-ray. Ref : Tsung A. (2010). Chapter 31. Liver. In T.R. Billiar, D.L. Dunn (Eds), Schwaz's Principles of Surgery, 9e.