<prompt> True statements regarding Zenkers diverticulum includeAspiration pneumonitis is unlikelyIt is a congenital abnormalityThe most common symptom is a sensation of high obstruction on swallowingIt is a traction-type diverticulum  <response>: Zenkers diverticulum is an acquired abnormality. Premature contraction of the cricopharyngeus muscle on swallowing, which leads to partial obstruction, is believed to be the cause of this pulsion-type diverticulum of the pharyngoesophageal junction. High intraluminal pressure results in an outpouching of mucosa through the oblique fibers of the pharyngeal constrictors. Dysphagia is common and is the usual presenting symptom. The diagnosis is established by barium swallow. Treatment is surgical: diverticulectomy or suspension of the diverticulum is usually recommended. Because the diverticulum is located above the superior esophageal sphincter, no mechanism exists to prevent aspiration of the contents of the diverticulum. Pulmonary complications are common. 