What is a Zenker’s diverticulum?

A Zenker’s diverticulum, more formally known as a hypopharyngeal diverticulum, is a pouch that can form at the junction of the hypopharynx (lower part of the throat) and the esophagus, an area known as Killian’s Triangle. This pouch typically causes problems by trapping food as it is being swallowed, leading to choking and aspiration.

What causes a Zenker’s diverticulum?

A Zenker’s diverticulum typically arises due to tightness of the cricopharyngeus muscle. This muscle makes up the upper esophageal sphincter, and is located just below the level of the voice box. Normally, it relaxes during swallowing to allow food to pass into the esophagus. When this muscle fails to relax, the pressure of swallowing pushes the food against the posterior wall of the hypopharynx, causing it to bulge slightly. The combination of obstruction, pressure and bulging, repeated over thousands of swallows, eventually leads to a permanent bulge or pouch — a Zenker’s diverticulum. The diverticulum continues to enlarge as more and more food is pressed into it.

What are the symptoms of Zenker’s diverticulum?

The classic symptoms of a Zenker’s diverticulum consist of difficulty swallowing, a feeling a lump or fullness in the throat, and subsequent regurgitation of undigested trapped food minutes to hours after eating. This unexpected regurgitation of food can lead to aspiration (food particles entering the windpipe and lungs) and, in some cases, pneumonia.

How is a Zenker’s diverticulum diagnosed?

A Zenker’s diverticulum is usually diagnosed radiographically with a study called a barium swallow. This study uses radioopaque liquid, barium, which is swallowed, revealing the contour of the hypopharynx and esophagus. The Zenker’s diverticulum is readily visible on the lateral view of a barium swallow. The indentation of the tight cricopharyngeus muscle may also be noticeable.

What are the risk factors of developing a Zenker’s diverticulum?

The risk of developing a Zenker’s diverticulum increases as a person ages. People with a history of neurological diseases, such as stroke, are particularly vulnerable to developing a Zenker’s diverticulum.

How is a Zenker’s diverticulum treated?

If a Zenker’s diverticulum is causing symptoms, surgical treatment may be recommended. Surgery generally consists of severing the tight cricopharyngeus muscle, and eliminating the pouch. Severing the muscle is critical to the success of this surgery. With a very small diverticulum, simply dividing the muscle can occasionally allow the pouch to decompress, creating a normal esophageal contour. With larger diverticula, muscle division must be combined with a procedure to eliminate the pouch. This can be performed through either an external or endoscopic approach. With an external approach, an incision is made in the neck allowing the surgeon to expose the esophagus. The cricopharyngeus muscle is identified and severed. The diverticulum pouch is identified and excised. With an endoscopic approach, no external incision is made. The esophagus and diverticulum are visualized through a specialized tube called a diverticuloscope placed through the mouth. The wall between these two structures is divided using an endoscopic stapler, which simultaneously severs the cricopharyngeus muscle and opens the diverticulum directly into the esophagus. Endoscopic diverticulectomy is now a relatively quick procedure that can be performed as an outpatient or with an overnight hospital stay.

By Cary Moorhead, MD