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What is Bird of prey sign is seen in and explain in detail?
Sigmoid volvulus is a cause of large bowel obstruction and occurs when the sigmoid colon twists on the sigmoid mesocolon. Imaging signs areRadiograph:coffee bean signFrimann Dahl&;s sign - three dense lines converge towards the site of obstructionabsent rectal gas water-soluble contrast enema - the beak sign (or bird beak sign). CTlarge gas-filled loop without haustral markings, forming a closed-loop obstructionwhirl sign: twisting of the mesentery and mesenteric vesselsbeak sign: if rectal contrast has been administered (Ref: Grainger and Allison&;s diagnostic radiology 6th edition, chapter 25)