Zenker's Diverticulum
Comprehensive information on the causes, symptoms, and treatment of esophageal protrusions.
Symptoms and Causes
Zenker's diverticulum is a disorder characterized by the formation of protrusions or pouches in the esophagus that gradually enlarge. These pouches usually develop as a result of increased pressure, which causes the mucosal and submucosal layers lining the esophagus to herniate outward through the muscular layer. Unlike other diverticula, the protrusion does not contain muscle tissue.
In most cases, Zenker's diverticula occur near the upper sphincter (prevents food from refluxing into the larynx) or lower sphincter (closes the stomach entrance to prevent gastric contents from ascending through the digestive tract) because these are areas of natural muscular weakness.
Zenker's diverticulum is a rare condition that, if it enlarges significantly over time, can substantially reduce quality of life and may lead to serious complications. Nevertheless, it has a favorable prognosis if appropriately treated.
Symptoms
The most characteristic symptoms of Zenker's diverticulum, which intensify as the condition progresses, include:
- Dysphagia: difficulty swallowing, usually affecting the passage of food from the mouth to the esophagus (oropharyngeal dysphagia).
- Neck discomfort.
- Sialorrhea or ptyalism: excessive salivation.
- Noisy swallowing: audible sounds during deglutition.
- Gurgling in the posterior throat.
- Halitosis: bad breath.
- Hoarseness.
- Regurgitation: passive return of food from the esophagus to the mouth without nausea or effort.
- Sensation of food being stuck.
- Choking.
- Weight loss.
If microaspiration occurs when small amounts of food or fluids enter the lungs it may manifest as:
- Cough, which may produce sputum or blood.
- Chest pain.
- Dyspnea.
- Fatigue.
- Voice changes.
- Wheezing.
- Tussive syncope: loss of consciousness triggered by intense coughing.
Some patients are asymptomatic, especially in the early stages of the disease.
Causes
The exact causes of Zenker's diverticulum are not fully understood, though it is thought to be associated with esophageal muscular dysfunction. When the muscles fail to relax properly to allow the passage of food, food may become trapped, promoting the formation of a tissue pouch.
Some studies suggest that asynchronous movement of the esophageal muscles and the upper esophageal sphincter (contraction of the esophageal walls not synchronized with sphincter relaxation) leads to increased pharyngeal pressure, favoring mucosal protrusion through Killian's triangle, the most common site of Zenker's diverticulum.
Killian's triangle is an area in the posterior pharynx that is naturally weak, where the horizontal fibers of the cricopharyngeal muscle and oblique fibers of the inferior pharyngeal constrictor muscle converge.
Risk Factors
Key risk factors for developing Zenker's diverticulum include:
- Age: more frequent between 50 and 80 years.
- Sex: higher incidence in males.
- Gastroesophageal reflux: upward movement of gastric contents into the esophagus.
- Hiatal hernia: part of the stomach protrudes into the chest through the diaphragm.
- Previous esophageal surgeries.
Complications
Zenker's diverticulum may lead to the following complications:
- Aspiration pneumonia: lung infection due to microaspiration.
- Malnutrition.
- Esophageal obstruction: if the protrusion grows excessively.
- Occasionally, tracheoesophageal fistula: a connection between the diverticulum and the trachea.
- Rarely, carcinoma: cellular changes within the diverticulum may lead to squamous cell carcinoma.
- Diverticulitis: inflammation and infection of the diverticulum.
Prevention
Zenker's diverticulum cannot be prevented. However, to minimize worsening and avoid complications, it is recommended to:
- Follow a diet of soft foods, avoiding hard or shelled items that may become lodged.
- Consume small portions and chew thoroughly before swallowing.
- Hydration: drink water between bites to facilitate passage of food.
Which Specialist Treats Zenker's Diverticulum?
Zenker's diverticulum is managed by Otorhinolaryngology or General and digestive system surgery specialists.
Diagnosis
After gathering relevant patient history and symptoms, the following tests are commonly used to diagnose Zenker's diverticulum:
- Videofluoroscopic swallow study: a contrast medium is administered with food or liquid, and X-rays capture dynamic images of swallowing mechanics in real time. This test evaluates the behavior of the bolus in the mouth and pharynx.
- Esophageal transit study or barium esophagogram: similar to the above but focuses on food passage through the esophagus. It detects obstructions and structural abnormalities.
In patients already diagnosed with a history of microaspiration, pulmonary function testing is performed before planning surgery. Typically, spirometry is used to measure the volume and speed of air expelled.
Treatment
Treatment of Zenker's diverticulum focuses on removing the protrusion and repairing tissues to prevent recurrence. Depending on the size and location of the pouch and patient-specific characteristics, various procedures may be performed:
- Endoscopic treatment: a minimally invasive alternative to open surgery, which carries higher risks. Under general anesthesia, a tube with a camera is inserted orally. Guided by imaging, the specialist removes the diverticulum using a laser (endoscopic diverticulectomy) or electrocautery.
- Rigid endoscopy: uses a non-flexible tube.
- Flexible endoscopy: the tube adapts to anatomy along the digestive tract; commonly used with electrocautery.
- Open surgery: an incision is made in the neck to access the diverticulum. Optimal results often combine two techniques:
- Diverticulectomy: the protruding tissue is excised using laser or electrocautery, similar to endoscopy.
- Cricopharyngeal myotomy: the cricopharyngeal muscle is cut to relieve esophageal pressure and facilitate swallowing.
