An unusual presentation of Zenker's diverticulum.

Zenker's diverticula are esophageal outpouchings in the region of the cricopharyngeus which typically grow in a posterolateral and inferior direction and can cause esophageal compression if the diverticulum is large enough. We describe a patient in whom a Zenker's diverticulum expanded posteriorly and superiorly so that it was positioned in the posterior pharyngeal space, causing both esophageal and tracheal narrowing.