What is Zenker’s diverticulum?
Zenker’s diverticulum (ZD) is also known as pharyngeal pouch.
It is an abnormal sac-like structure forming off the natural weak area on the wall of the throat. It locates at the junction between the pharynx (membrane-lined cavity behind the nose and mouth) and the esophagus (food pipe).
Who gets Zenker’s diverticulum?
ZD occurs most commonly in elderly patients. It is rare before the age of 40 years. It is typically seen in older adults in their seventh or eighth decade of life.
Males are more commonly affected by ZD with the men to women ratio of about 1.5:1.
What are the causes?
Causes of ZD’s development have been a topic of much debate.
The most accepted theory involves building up of pressure within the throat as a result of 1) abnormal tightening of upper esophageal sphincter (UES) and 2) high throat muscle resting tone.
[Note: UES is an area of the upper digestive tract that forms a barrier between the esophagus and the pharynx. It can close or open intermittently to allow passage of food during swallowing.]
During swallowing, pressure inside the throat significantly increased and is a lot higher than the outside in those with tight EUS and high throat muscle resting tone. The unusually large pressure difference created at the natural weak area causes the throat wall to protrude and form a sac-like structure. Tight esophageal sphincter and high resting tone also make it harder for food to pass down into the esophagus during swallowing. Instead of being passed down the esophagus, some food is passed into the abnormal sac and collected there.
There are some conditions that predisposed patients to ZD formation. The examples include UES dysfunction, abnormal esophageal motility, and gastroesophageal reflux disease (GERD).
[Note: GERD is also known as acid reflux, is a condition in which stomach contents leak back up into the esophagus, resulting in symptoms such as acidic taste in the back of the throat, heartburn, bad breath.]
Initially, patient with ZD are often asymptomatic. As the pouch continue to grow, the patients will start to develop more symptoms that can progressively get worse as the pouch become larger.
The most common symptom of ZD is progressive dysphagia (difficulty swallowing) to liquids and solids.
Once the diverticular sac becomes large enough to retain contents such as undigested food, mucus or sputum, patients may complain of:
- Food regurgitation (swallowed food brought back up into the mouth)
- Halitosis (foul-smelling breath)
- Cervical borborygmus (gurgling sound in the lower neck)
- Appearance of neck mass
- Voice changes
Regurgitation of undigested food usually occur hours after eating, commonly at night when patients are lying down flat. Regurgitation often leads to coughing or aspiration (food sucked into the airway).
How is it diagnosed?
Barium swallow test is widely used to confirm the diagnosis of ZD. It is a type of imaging test that uses X-ray and barium to create images of the mouth, throat and esophagus.
In addition, ZD may be diagnosed using ultrasonography (USS). This method is useful to differentiate ZD from other conditions such as thyroid nodules or other causes of neck mass. It is also an alternative option for those who cannot tolerate barium swallow or have difficulty swallowing.
Upper endoscopy is not required to establish ZD diagnosis but can provide useful information such as exclusion of associated cancer. The process involves insertion of a flexible, narrow tube with camera attached into the patient’s mouth and into the digestive tract for direct visualization.
*For health professionals*
In patient with ZD, posterior outpouching of the esophagus is seen at the level of sternoclavicular joint during barium esophagography. It can be combined with dynamic continuous fluoroscopy to allow better visualization of ZD as static images may be insufficient in those with small diverticulum and provide evidence of overflow and aspiration.
Findings from dynamic fluoroscopy are used to determine Lahey Classification of ZD:
- 1st stage – small mucosal protrusion is visible
- 2nd stage – a definite sac is seen but the esophagus and hypopharynx are in line
- 3rd stage – the hypopharynx is seen in line with the diverticulum and the esophagus is pushed anteriorly and appears indented.
During USS, findings such as increase in size, reduction of margin’s definition and heterogenous echogenicity observed upon swallowing water are suggestive of ZD.
What are the potential complications?
Complications of ZD includes:
- Ulceration and bleeding due to medication lodged inside diverticulum
- Aspiration pneumonia (a type of lung infection that occurs after inhalation of food or liquid into the lungs)
- Fistula (abnormal connection) between ZD pouch and trachea (windpipe)
- Paralysis of the vocal cord muscle due to pressure from retained contents
Malnourishment and weight loss secondary to difficulty swallowing
*For health professionals*
Squamous cell carcinoma (SCC) rarely occurs as a complication of ZD as a result of chronic irritation and inflammation secondary to food stasis. ZD-associated SCC incidence ranges from 0.3-0.5%.
Rarely, cancer of the esophagus can occur as a result of chronic irritation and inflammation from prolonged food retention. The risk of cancer development is higher in older patient, male sex, patient with long history of ZD, and large ZD size.
Cancer should be suspected in the presence of:
- Odynophagia (painful swallowing)
- Hemoptysis (coughing up of blood)
- Hematemesis (vomiting of blood)
- Constitutional symptoms (e.g. weight loss, fevers, malaise and lymph node enlargement)
*For health professionals*
Endoscopic approaches gained popularity in recent times as they were shown to be safe and effective and allow fast recovery.
Rigid endoscopy is done under general anesthesia with diverticuloscope. Examples of the coagulation and cutting techniques to use with rigid endoscopy includes stapler assisted method, Harmonic scalpel or LigaSure, and CO2 laser.
In contrast, flexible endoscopy does not require general anesthesia. This makes it an attractive option for patients who are poor surgical candidates. However, the procedure requires special expertise. Furthermore, evidence suggests a higher ZD recurrence rate and need for surgical revisions in patients who had flexible endoscopic surgery than those who had rigid endoscopic surgery.
What are the treatment options?
ZD that is asymptomatic and small (<1cm) is unlikely to require surgical intervention and can be manage by just ‘watchful waiting’. Some lifestyle modifications can be helpful for managing symptoms such as chewing food thoroughly and drinking a lot of fluid after a meal.
Surgery is a definitive treatment for symptomatic and large (>1cm) ZD. It can lead to reduction or resolution of symptoms and improvement in quality of life.
There are a few types of surgery to treat ZD. Few important considerations for selecting type of surgery are patient’s body size, comorbidities, location and size of ZD, and surgeon expertise and preference.
*For health professionals*
- Cricopharyngeal myotomy (i.e. surgical sectioning of UES) – for removal of small ZD and can be done using open or trans-oral approach.
- Cricopharyngeal myotomy with diverticulectomy – for removal of larger ZD involving complete removal of ZD sac.
- Cricopharyngeal myotomy with diverticulopexy – for removal of larger ZD involving turning the sac upside down and suture it to the esophageal wall to prevent food collection.
- Endoscopic diverticulotomy (‘Dohlman procedure’) – divides the septum between the esophagus and the ZD pouch allowing food to drain freely down the esophagus and prevent food collection.
What is the prognosis?
Prognosis of patient with ZD is dependent on management modalities and patient factors such as age and comorbidities. With treatment, most people experience significant improvement in symptoms. Long term recurrence rate is up to about 50% in patients who undergone surgery.
*For health professionals*
Conventional open surgery has high success rate ranging from 80 to 100% but complication and mortality rates are reported to be as high as 30% and 3%, respectively.
Mediastinitis, esophageal stenosis, recurrent laryngeal nerve damage, pharyngocutaneous fistula, hematoma, and esophageal perforation are examples of morbidities from open surgery.
In those who had stapler-assisted surgery, immediate symptoms relief achieved in 94% to 100% of patients. The long-term symptoms recurrence rate ranges from zero to 47%. With low mortality rate of 0% to 1% and morbidity rate of 10% to 31%. Recurrent laryngeal nerve damage, bleeding, mediastinitis, dental injury, esophageal perforation, diverticulum perforation, and cervical emphysema are examples of
Impact on DALY?
Untreated ZD can lead to a significant impairment of a patient’s quality of life as the condition progress. The condition makes food consumption unpleasant and dangerous due to risk of choking.
In addition, foul-smelling breath, a symptom secondary to retained food within the pouch, can negatively impact the patient’s physical and psychological health and interpersonal relationships.
What Is Zenker’s Diverticulum and How Is It Treated? https://www.healthline.com/health/zenkers-diverticulum#symptoms
Treatment of Zenker’s diverticulum https://www.mayoclinic.org/medical-professionals/digestive-diseases/news/treatment-of-zenkers-diverticulum/mac-20431393
About barium swallow test – https://www.healthnavigator.org.nz/health-a-z/b/barium-swallow/
- Siddiq MA, Sood S, Strachan D. Pharyngeal pouch (Zenker’s diverticulum). Postgraduate medical journal. 2001;77(910):506-11.
- Herbella FAM, Dubecz A, Patti MG. Esophageal diverticula and cancer. Diseases of the Esophagus. 2012;25(2):153-8.
- Bizzotto A, Iacopini F, Landi R, Costamagna G. Zenker’s diverticulum: exploring treatment options. Acta Otorhinolaryngologica Italica. 2013;33(4):219.
- Sen P, Bhattacharyya AK. Endoscopic stapling of pharyngeal pouch. The Journal of Laryngology & Otology. 2004;118(8):601-6.
- Krespi Y, Kacker A, Remacle M. Endoscopic treatment of Zenker’s diverticulum using CO2 laser. Otolaryngology—Head and Neck Surgery. 2002;127(4):309-14.
- Fama AF, Moore EJ, Kasperbauer JL. Harmonic scalpel in the treatment of Zenker’s diverticulum. The Laryngoscope. 2009;119(7):1265-9.
- Case DJ, Baron TH, editors. Flexible endoscopic management of Zenker diverticulum: the Mayo Clinic experience2010: Elsevier.
- Dhingra PL, Dhingra S. Diseases of Ear, Nose and Throat-eBook: Elsevier India; 2017.
- Law R, Katzka DA, Baron TH. Zenker’s diverticulum. Clinical Gastroenterology and Hepatology. 2014;12(11):1773-82.
- Chang CY, Payyapilli RJ, Scher RL. Endoscopic staple diverticulostomy for Zenker’s diverticulum: review of literature and experience in 159 consecutive cases. The Laryngoscope. 2003;113(6):957-65.
- Bonafede JP, Lavertu P, Wood BG, Eliachar I. Surgical outcome in 87 patients with Zenker’s diverticulum. The Laryngoscope. 1997;107(6):720-5.
- Nesheiwat Z, Antunes C. Zenker Diverticulum. StatPearls [Internet]: StatPearls Publishing; 2019.
- Crawley B, Dehom S, Tamares S, Marghalani A, Ongkasuwan J, Reder L, et al. Adverse Events after Rigid and Flexible Endoscopic Repair of Zenker’s Diverticula: A Systematic Review and Meta-analysis. Otolaryngology–Head and Neck Surgery. 2019;161(3):388-400.
- Lixin J, Bing H, Zhigang W, Binghui Z. Sonographic diagnosis features of Zenker diverticulum. European journal of radiology. 2011;80(2):e13-e9.
- Cook IJ, Gabb M, Panagopoulos V, Jamieson GG, Dodds WJ, Dent J, et al. Pharyngeal (Zenker’s) diverticulum is a disorder of upper esophageal sphincter opening. Gastroenterology. 1992;103(4):1229-35.
- Sasaki CT, Ross DA, Hundal J. Association between Zenker diverticulum and gastroesophageal reflux disease: development of a working hypothesis. The American journal of medicine. 2003;115(3):169-71.
- Liu JJ, Kahrilas PJ. Pharyngeal and esophageal diverticula, rings, and webs. GI Motility online. 2006.
- Kensing KP, White JG. Massive bleeding from a Zenker’s diverticulum: case report and review of the literature. Southern medical journal. 1994;87(10):1003-4.
- Sharma R, DeCross AJ. Zenker’s diverticulitis secondary to alendronate ingestion: a rare cause of recurrent dysphagia. Gastrointestinal endoscopy. 2011;73(2):368-70.
- Nehring P, Krasnodębski IW. Zenker’s diverticulum: aetiopathogenesis, symptoms and diagnosis. Comparison of operative methods. Przeglad gastroenterologiczny. 2013;8(5):284.
- Payne WS. The treatment of pharyngoesophageal diverticulum: the simple and complex. Hepato-gastroenterology. 1992;39(2):109-14.
- Mantsopoulos K, Psychogios G, Künzel J, Zenk J, Iro H, Koch M. Evaluation of the different transcervical approaches for Zenker diverticulum. Otolaryngology–Head and Neck Surgery. 2012;146(5):725-9.
- Rösing CK, Loesche W. Halitosis: an overview of epidemiology, etiology and clinical management. Brazilian oral research. 2011;25(5):466-71.
Author + Affiliation:
Date of Publication +/- Review: