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What is Bird beak sign on barium swallow is seen in? and explain in detail?
Ans. is 'a' i.e., Achlasia cardia * "Bird beak appearance on barium study is seen in achlasia cardia.Important esophageal signs on radiographySignConditionRat tail appearance of esophagusEsophageal carcinomaMega-esophagus (sigmoid esophagus)"Bird beak" appearanceHurst phenomenonAchlasia cardiaYo-Yo motion of barium"Corkscrew" appearance (esophageal curling)Rosary-bead/sheikh kebab configurationChain of bead appearanceDiffuse esophageal spasm