Cricopharyngeal Bar and Zenker Diverticulum

G&H Could you define the terms “cricopharyngeal bar” and “Zenker diverticulum”?

IC A cricopharyngeal bar is a radiologic descriptor of a posterior impression at the pharyngoesophageal segment. The cricopharyngeal bar is a frequent incidental radiologic finding, which in many cases does not cause symptoms.

Zenker diverticulum is invariably associated with a restrictive defect or cricopharyngeal bar at the same radiologie location. This condition is characterized by a posterior herniation of mucosa and submucosa through an area of relative weakness just above or proximal to the cricopharyngeus muscle. While the isolated finding of a cricopharyngeal bar is frequently an incidental finding, in the context of an associated diverticulum the combined pathology generally accounts for a patient's symptoms (dysphagia and regurgitation).

G&H If a patient with a cricopharyngeal bar or Zenker diverticulum is symptomatic, what are the usual presenting symptoms?

IC The most common symptom that prompts a barium swallow study that finds the cricopharyngeal bar is dysphagia. However, as I have already implied, the finding of the bar in this context should not be taken as proof that the bar is causing the patient's dysphagia; the patient's symptoms are often caused by other problems, not infrequently distal to the bar in the esophagus. It must be appreciated that approximately 30% of individuals who have dysphagia caused by an esophageal problem— whether it is structural or motor-related—localize the apparent holdup of food to their neck. What frequently happens is that these patients undergo a barium swallow study, a cricopharyngeal bar is identified, and the clinician erroneously jumps to the conclusion that the bar is causing the symptoms. Thus, it is important to keep in mind that a cricopharyngeal bar is frequently a red herring. In a large systematic study, a cricopharyngeal bar was identified in 19% of cases, but esophageal pathology that accounted for the dysphagia was identified in one third of these cases.

The classic symptoms of Zenker diverticulum are dysphagia and regurgitation, often immediately or soon after ingesting food or liquid; regurgitation may also occasionally occur several hours after a meal. When Zenker diverticulum is severe, patients may present with weight loss. Occasionally, patients can present solely with pulmonary complications such as pneumonia. Sometimes, patients with unexplained, recurrent pneumonia present with “vomiting” that is actually regurgitation, aspiration (often at night), and less prominent dysphagia. Very rarely, patients can present with pain, bleeding, ulceration, or tumor development in the diverticulum.

G&H How frequently are patients with these conditions asymptomatic?

IC Zenker diverticulum has been found postmortem, incidentally, or on barium swallow studies administered for indications other than dysphagia. However, the true prevalence of asymptomatic diverticula is unknown.

As previously mentioned, asymptomatic cricopharyngeal bars are common. The prevalence of bars, either symptomatic or asymptomatic, is much higher than the prevalence of Zenker diverticulum. Curtis and colleagues detected cricopharyngeal bars in 5–19% of individuals