Oesophageal diverticulum (Zenker's and epiphrenic)
An oesophageal diverticulum is an outpouching of the oesophageal wall. It is uncommon. Its importance is that it is almost never a primary disease of the oesophageal wall — it is the visible consequence of a functional problem elsewhere in the swallowing mechanism. Treating the pouch without treating the cause is the commonest reason these operations fail.
How they form
Diverticula are classified by mechanism, and the mechanism determines the treatment.
Pulsion diverticula arise from inside. Raised pressure within the oesophageal lumen, generated against an outflow obstruction, forces the mucosa and submucosa outward through a weak point in the muscular wall. Because only the inner layers herniate, these are false diverticula — they have no muscle in their wall.
Traction diverticula arise from outside. Inflamed mediastinal lymph nodes, classically tuberculous, scar and contract, pulling the full thickness of the oesophageal wall with them. These are true diverticula, containing all layers, and are usually mid-oesophageal, small and asymptomatic.
Zenker's diverticulum (pharyngeal pouch)
The commonest and most important. It is not strictly oesophageal: it arises just above the upper oesophageal sphincter, through Killian's dehiscence — a triangular area of relative weakness between the oblique fibres of the thyropharyngeus and the transverse fibres of the cricopharyngeus.
The underlying abnormality is failure of the cricopharyngeus to relax and open properly during swallowing, probably with reduced compliance of the muscle itself from fibrosis. Each swallow generates pressure against a sphincter that does not open fully, and over years the mucosa is forced out through the weak point. The pouch then enlarges downward behind the oesophagus, and as it fills it compresses the oesophagus in front of it, which worsens the obstruction and accelerates its own growth.
This is why simply removing the pouch is inadequate: the cricopharyngeus must be divided, or the problem recurs.
Epiphrenic diverticulum
Arises in the lower oesophagus, within the last 10cm, and is a pulsion diverticulum driven by an underlying motility disorder — achalasia in a substantial proportion, or distal oesophageal spasm, hypercontractile oesophagus, or an incompletely relaxing lower sphincter. Manometry is therefore mandatory before any operation, because the myotomy is the operation and the diverticulectomy is the secondary part of it.
Symptoms
Many are found incidentally on barium swallow or CT and cause nothing.
Zenker's produces a characteristic history that is worth recognising, because it is often attributed to reflux or to age for years:
- dysphagia, particularly a sensation of food sticking in the throat
- regurgitation of undigested food, sometimes hours later or from the pillow at night
- halitosis, from food retained and fermenting in the pouch
- gurgling in the neck on swallowing
- a swelling in the left side of the neck that can sometimes be emptied by pressure
- cough, recurrent chest infections and aspiration pneumonia — the complication that makes this worth treating in older patients
- weight loss
- difficulty swallowing tablets, which may fail to reach the stomach at all
Epiphrenic diverticula produce dysphagia, regurgitation, chest pain and nocturnal aspiration, but the symptoms often reflect the motility disorder more than the pouch.
How the diagnosis is made
- Barium swallow is the key investigation. It demonstrates the pouch, its size and its neck, and shows the dynamic relationship with the sphincter. It is more informative than endoscopy here.
- Endoscopy is performed with care, since a pouch can be entered inadvertently and perforated. It excludes other pathology and, rarely, identifies carcinoma arising within a long-standing pouch.
- Manometry is essential for epiphrenic diverticula and informative in Zenker's, though the pouch can make the study technically difficult.
- CT where the anatomy is complex or malignancy suspected.
When treatment is needed
Asymptomatic diverticula, and small incidental mid-oesophageal traction diverticula, are left alone. Treatment is for symptoms — dysphagia, regurgitation, and above all aspiration, which in an older patient is a genuine threat to life rather than an inconvenience.
Treatment
Zenker's diverticulum
Every effective treatment divides the cricopharyngeus. The approaches differ in how they reach it.
- Endoscopic (transoral) stapling or diverticulotomy — a rigid or flexible endoscope is used to divide the common wall between pouch and oesophagus, which contains the cricopharyngeus. The pouch is not removed; it is made continuous with the oesophagus so it no longer retains food. Quick, no neck incision, rapid return to eating, short hospital stay. Suited to medium and large pouches; very small pouches leave too little common wall to divide safely, and access requires adequate neck extension and mouth opening.
- Flexible endoscopic septotomy, including Z-POEM (a submucosal tunnelling technique), is increasingly used and avoids the need for rigid endoscopy and general neck extension — useful in frail patients.
- Open transcervical surgery — through a left neck incision, with cricopharyngeal myotomy plus either excision of the pouch (diverticulectomy), inversion, or suspension (diverticulopexy) depending on size. This remains the approach for very large pouches, very small pouches, recurrence after endoscopic treatment, and where transoral access is impossible.
Recurrence is higher after endoscopic treatment than after open surgery, but the trade-off in morbidity usually favours the endoscopic route, and a recurrence can generally be treated again endoscopically.
Epiphrenic diverticulum
The operation is a long myotomy addressing the underlying motility disorder, extending from below the diverticulum across the lower oesophageal sphincter onto the stomach, combined with diverticulectomy and usually a partial fundoplication to limit the reflux that follows. It is performed laparoscopically, thoracoscopically or, increasingly, endoscopically in selected patients.
The staple line leak is the feared complication, and its risk is directly related to whether the distal obstruction has been relieved: a diverticulectomy performed without an adequate myotomy is a staple line closed against persisting high pressure.
Recovery
After endoscopic treatment of a Zenker's, patients typically stay one night, often start fluids the same or next day, and return to normal diet within days. After open surgery or epiphrenic repair, a contrast study usually precedes feeding, hospital stay is longer, and a soft diet is followed for two to four weeks.
Recognised complications include perforation and mediastinitis, temporary or permanent hoarseness from recurrent laryngeal nerve injury in open neck surgery, and, after distal procedures, reflux.
Follow-up
Symptom review, with barium swallow where symptoms recur. Carcinoma arising within a very long-standing Zenker's pouch is rare but described, and persistent or changing symptoms in a patient with a pouch of many years' standing warrant endoscopic assessment rather than reassurance.
Common questions
Why does food come back up hours after I have eaten?
Because it is not coming from the stomach. It has been sitting in a pouch in the neck or lower oesophagus, where there is no acid, which is why it tastes of the food itself rather than sour. Bringing up undigested food on the pillow at night is a classic sign of a pouch.
Is it cancer?
No. A diverticulum is a pouch in the wall of the swallowing tube, not a growth. Cancer arising in a very long-standing pouch is rare but recognised, which is why an endoscopy is usually part of the assessment.
Do I have to have it treated?
Not if it causes no trouble. Treatment is advised when it causes difficulty swallowing, regurgitation, weight loss, or — most importantly — when food or fluid is going into the lungs, which causes chest infections and is the reason not to simply live with it.
Is there an operation without a cut in my neck?
Usually yes. Most pharyngeal pouches can now be treated through the mouth with an endoscope, dividing the muscle that is causing the blockage. It is quicker, recovery is faster, and there is no scar. Suitability depends on the size of the pouch and on being able to extend the neck and open the mouth sufficiently.
Why do you divide a muscle rather than just remove the pouch?
Because the pouch is a consequence, not the cause. A muscle at the top of the gullet fails to open properly when you swallow, and the pressure this creates pushes the lining out through a weak spot. If that muscle is not divided, the pouch simply forms again.
Can it come back?
It can, more often after treatment through the mouth than after open surgery. Recurrence is usually treatable again by the same route. Returning symptoms — food sticking, regurgitation, bad breath — are the signal to be reassessed.
Why do I have bad breath?
Food retained in the pouch ferments. It is not a problem of oral hygiene, and it will not respond to mouthwash. It resolves when the pouch is treated.
Related conditions
Other conditions of the oesophagus covered on this site:
- Gastro-oesophageal reflux disease (GORD) and hiatus hernia
- Paraoesophageal hernia
- Achalasia
- Barrett's oesophagus
- Benign tumours of the oesophagus
- Oesophageal cancer
- Oesophageal perforation and Boerhaave syndrome
This page provides general information and does not replace an individual medical consultation. Assessment and treatment are decided for each patient after review of their history, examination and investigations.