An esophageal diverticulum is a pouch, or pocket, of stretched tissue that develops anywhere along the esophagus, pushing outward through its muscular wall. They are rare, and can be congenital or acquired. Typically a single pouch forms, most often near the top of the esophagus; this is called Zenker’s diverticulum. In other cases, a pouch forms nearer to the bottom of the esophagus (epiphrenic) or, less frequently, in the middle. A single diverticulum ranges from 1 to 4 inches in diameter. Very rarely, tiny (~5 mm) diverticula emerge along the entire length of the esophagus, numbering from a few to a hundred or more. This condition, called intramural pseudodiverticulosis, is pathogenically different from the other pouches, but is associated with
poor esophageal motility
Non-congenital diverticula develop from a combination of uneven pressure and weak areas of muscle and tissue in the esophagus. Pressure can stem from structural disorders (i.e., a malfunctioning sphincter muscle at either end of the esophagus), from poor coordination of the swallowing mechanism, poor movement of food through the esophagus, and from inflammation on the outside of the esophagus that pulls on its wall.
Diverticula do not always cause problems. Some collect food, which can lead to food regurgitation, dysphagia (difficulty swallowing), chest pain, aspiration pneumonia, and feeling a need to clear one’s throat. As food collects in the pockets, it promotes bacteria in the esophagus, which commonly leads to halitosis (bad breath).
Esophageal diverticula that are asymptomatic or only minimally annoying can go without treatment. Other cases might be treated with a change to a bland diet and increased water intake and/or antacids. Patients with more problematic diverticula, including those with underlying motility disorders, might require minimally invasive or open surgery, or other procedures such as repeated mechanical dilations of the esophagus.
Diverticula do not always cause problems. Food regurgitation might occur when standing, bending or lying down. Patients might develop dysphagia (difficulty swallowing), chronic coughing, chest pain, heartburn and weight loss. In advanced cases, food can more easily be drawn into the lungs, causing aspiration pneumonia. As food collects in the pockets, it promotes bacteria in the esophagus, which also leads to halitosis (bad breath). A patient’s voice also might change.
Esophageal diverticula can be congenital or acquired, usually developing later in life. Most of the acquired cases are associated with a motility disorder, such as achalasia, related to malfunctioning sphincter muscles at the upper (Zenker’s) or lower (epiphrenic) end of the esophagus, and/or along its length (pulsion diverticula), and/or with swallowing dysfunction. Weak areas of tissue can develop as repeated obstructions build pressure inside the esophagus.
A Zenker’s diverticulum stems from increased pressure in the throat during swallowing against a closed upper esophageal sphincter. An epiphrenic diverticulum occurs from increased pressure against a closed lower esophageal sphincter as contractions move food along the esophagus. Inflammation of tissues outside the esophagus, in the mediastinum – the chest cavity in which the esophagus and other structures exist – can cause traction diverticula in the mid or lower esophagus.
Rarely, diverticula can stem from an unrelated surgery to the esophagus and from Ehlers-Danlos syndrome (weakness of collagen).
Most esophageal diverticula occur in adults over 50, especially those in their 70s and 80s. Very rarely, diverticula are present in infants and children. People who have a swallowing or esophageal-motility disorder, or esophagitis (inflamed lining) are more prone to develop diverticula.
A physical exam could reveal a bulge in the neck, which might indicate a Zenker’s diverticulum. But more often, diagnostic tests help discern the presence of esophageal diverticula. A specialist can examine the patient’s esophagus with a thin, flexible tube called an endoscope, which is directed down the patient’s throat, into the esophagus. Its end has a light and miniature camera, enabling the physician to view the anatomy up-close on a video monitor. The camera also produces high-resolution images, which the physician can study or use in consultation with another specialist. The procedure is typically performed with a topical anesthesia to numb the patient’s throat.
A patient might be asked to swallow an opaque barium solution that, when imaged with a CT scanner, will define the diverticulum’s structure and position, and might offer insight to an underlying motility problem. Chest X-rays and CT scans depict large esophageal diverticula as air- or fluid-filled balloons. Manometry measures the internal pressure of the esophagus at various points along its length, evaluating its ability to move food downward.
Each of these procedures is typically done on an outpatient basis in clinic.
Rarely, an esophageal diverticulum might rupture, causing internal bleeding. Rarely, cancer is associated with presence of an esophageal diverticulum. Although most surgical procedures to remove diverticula have excellent long-term outcomes, risks exist:
- Part of the lung often must be collapsed completely so the physician can clearly view the esophagus and diverticulum. However this is rarely necessary at UW Medical Center since most such procedures can be performed laparoscopically.
- Leakage through sutures at the site where the diverticulum was removed
- Injury to the vagus nerves might occur during dissection of the esophagus.
A bland diet, increased water intake after meals, a regimen of antacids and being attentive to physical movement and the body’s position (e.g., lesser activity; sitting or standing instead of lying down) soon after eating might help a patient manage a less-disruptive diverticulum.