Appearance of Cricopharyngeal achalasia in X-ray

It appeares as :Hemispherical or horizontal, shelflike protrusion on the posterior aspect of the esophagus at approximately the C5-C6 level.

Short Comment.......It is Failure of the upper esophageal sphincter to relax. Can result in dysphagia by obstructing the passage of a swallowed bolus. In severe disease, can cause aspiration and pneumonia.