<prompt> Answer this question truthfullyWhat is a CT scan for Zenkers diverticulum?  <response>: <reason> ZD appears as an out-pouching sac on the CT scan over the posterior esophagus in the Killians triangle, a point of weakness in the muscular wall of the hypopharynx surrounded by the cricopharyngeal sphincter and oblique fibers of the inferior constrictor of the pharyngeal muscle.CT-Zenkers diverticulum Source:Radiopaedia 