Zenker's diverticulum is a condition characterized by a pouch that can form at the junction of the hypopharynx (lower part of the throat) and the esophagus. This is an area known as Killian's Triangle. This pouch typically causes problems by trapping food as it is being swallowed, leading to dysphagia (difficulty swallowing), regurgitation of undigested food, choking and aspiration (food particles entering the windpipe and lungs).
A Zenker's diverticulum typically arises due to tightness of the muscle located just below the level of the voice box. Normally, this muscle relaxes during swallowing to allow food to pass. If the muscle repeatedly fails to relax, the pressure of swallowing pushes the food against the back 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 called a Zenker's diverticulum.
Zenker's diverticulum is generally categorized as small, intermediate, or large, depending on the size of the pouch. The condition appears more often in people over 50, and affects more men than women.
While Zenker's diverticulum is well understood, experts don't know specifically what causes it. A careful diagnosis is important since there are other conditions that can mimic Zenker's diverticulum. A physical examination and patient history are also important parts of diagnosis.
ZD is generally diagnosed using a barium swallow (also called a contrast esophagram). The patient drinks a barium-containing liquid, which coats the inside of the esophagus and makes its shape and contours appear on x-rays.
Treatment for Zenker's diverticulum is based on the severity of symptoms. No medications are available that will treat Zenker's diverticulum and surgery is the only treatment that will permanently relieve symptoms.
There are two common surgeries performed for treatment of Zenker's Diverticulum; open surgery and endoscopic surgery. The best surgery for any specific patient depends on medical health, diverticulum size, and neck mobility.
In open surgery a small cut is made in the neck and the pouch and esophagus are identified. The pouch is removed the defect is stapled. The cricopharyngeus muscle, located at the neck of the pouch, is cut to prevent reformation.
Endoscopic surgery is becoming a more widely used option. Endoscopic surgery for Zenker's diverticulum is minimally invasive approach in which the pouch is treated entirely through the mouth without the need for a cut on the skin. With the patient under general anesthetic esophagoscopy is used to identify the pouch. The overactive muscle is noted and cut with a laser or a stapler.
Endoscopic cricopharyngeal myotomy is a minimally invasive approach through the mouth. With the patient asleep a laryngoscope is placed through the mouth and positioned behind the voice box. The muscular cricopharygeal bulge is identified and a laser is used to cut this muscle. A stapler may also be used to cut the muscle as well.
Success rate for surgery is well over 90% with most patients able to swallow normally soon afterwards. Endoscopic diverticulectomy is now a relatively quick procedure that can be performed as an outpatient or with an overnight hospital stay.