Zenker diverticulum is a pulsion-type false diverticulum occurring at the posterior pharyngoesophageal junction (Killian dehiscence — triangular weak area between the inferior constrictor and cricopharyngeal muscles). It is the most common esophageal diverticulum in elderly adults (>60 years). Cricopharyngeal muscle dysfunction and increased pharyngeal pressure lead to herniation of mucosa and submucosa outside the muscularis propria. Most patients present with progressive dysphagia, regurgitation (undigested food), halitosis, and aspiration pneumonia. Appears as a posterior, left-sided pouch on barium esophagram and is the gold standard for diagnosis.
Age Range
50-90
Peak Age
70
Gender
Male predominant
Prevalence
Uncommon
Zenker diverticulum develops at an anatomical weak point at the pharyngoesophageal junction: Killian dehiscence, the triangular area between the oblique fibers of the inferior constrictor muscle and the transverse fibers of the cricopharyngeal muscle (upper esophageal sphincter). Cricopharyngeal muscle dysfunction (incoordinate relaxation or hypertonia) leads to increased intraluminal pressure during swallowing. This increased pressure pushes the mucosa and submucosa at Killian triangle outside the muscularis propria (pulsion mechanism). Because the diverticulum does not contain muscularis propria, it is classified as a 'false' diverticulum. The diverticulum starts at the posterior midline but deviates to the left as it enlarges — due to weaker connective tissue support on the left side of the esophagus. Its appearance as a posterior outpouching on barium is due to this anatomical orientation. Food debris accumulating within the diverticulum can lead to inflammation, ulceration, and rarely squamous carcinoma development.
Barium-filled pouch at the posterior pharyngoesophageal junction on lateral barium. The pouch originates from Killian dehiscence and extends posteroinferiorly. This appearance is pathognomonic for Zenker diverticulum. Left deviation on AP view is characteristic.
Barium-filled pouch at the posterior pharyngoesophageal junction (C5-C7 level) on lateral view. The neck is narrow and the body is wide. The pouch fills with barium during swallowing and shows delayed emptying after swallowing. On AP view, the pouch deviates to the left. In large diverticula, the pouch may extend to the upper mediastinum.
Report Sentence
A barium-filled pouch measuring approximately ___ cm at the posterior pharyngoesophageal junction at C6-C7 level; consistent with Zenker diverticulum.
Protrusion of the cricopharyngeal muscle into the lumen from the posterior wall — 'cricopharyngeal bar'. Seen at C5-C6 level. The cricopharyngeal bar reflects the etiology of Zenker diverticulum (incoordinate sphincter relaxation). Bar prominence is best assessed during dynamic swallowing evaluation.
Report Sentence
Cricopharyngeal bar (posterior indentation) at C5-C6 level; consistent with cricopharyngeal dysfunction.
Pouch containing air and/or food debris posterior to the cervical esophagus. The pouch is localized in the prevertebral space and more prominent on the left. The diverticular wall is thin (no muscularis). In large diverticula, it may push the esophagus anteriorly, causing luminal narrowing.
Report Sentence
A pouch containing air/food debris measuring approximately ___ cm in the prevertebral space posterior to the cervical esophagus; consistent with Zenker diverticulum.
In complicated Zenker diverticulum, diverticular wall thickening, inflammatory changes in surrounding fat (diverticulitis), abscess formation, or perforation findings may be seen. Enhancing thickened wall and surrounding soft tissue infiltration indicate infectious complication.
Report Sentence
Wall thickening and inflammatory changes in surrounding fat of the Zenker diverticulum; consistent with diverticulitis.
Pouch containing hyperintense fluid on T2. Food debris shows heterogeneous signal. MRI demonstrates anatomical detail well but is not the primary modality for Zenker diagnosis — barium esophagram is the gold standard.
Report Sentence
Pouch containing hyperintense fluid on T2 posterior to the cervical esophagus; consistent with Zenker diverticulum.
Aspiration pneumonia as an important complication of Zenker diverticulum: consolidation and ground-glass opacities in bilateral lower lobes. Tree-in-bud pattern (endobronchial aspiration). Chronic changes in lung bases suggest recurrent aspiration.
Report Sentence
Consolidation and tree-in-bud opacities in bilateral lower lobes; in the context of known Zenker diverticulum, consistent with aspiration pneumonia.
Criteria
Diverticulum size <2 cm.
Distinct Features
Usually asymptomatic or mild dysphagia. Small posterior outpouching on barium. Conservative follow-up sufficient.
Criteria
Diverticulum size 2-6 cm.
Distinct Features
Progressive dysphagia, regurgitation, halitosis. Endoscopic treatment (Z-POEM, stapler diverticulotomy) preferred.
Criteria
Diverticulum size >6 cm. Rare.
Distinct Features
Extends to upper mediastinum. May be confused with mediastinal mass on CT. Pushes esophagus anteriorly. Surgery preferred.
Distinguishing Feature
SCC shows irregular mucosal destruction; Zenker is a smooth barium-filled pouch with intact mucosa
Distinguishing Feature
Duplication cyst is a closed cystic structure without luminal communication; Zenker diverticulum communicates with lumen via neck
Distinguishing Feature
Achalasia shows bird-beak and diffuse dilation at distal esophagus; Zenker is a focal outpouching at proximal pharyngoesophageal junction
Distinguishing Feature
Lipoma is intraluminal fat-density (-100 HU) solid mass; Zenker is cystic pouch containing air/fluid with posterior location
Urgency
routineManagement
surgicalBiopsy
Not NeededFollow-up
specialist-referralTreatment is required for symptomatic Zenker diverticula. Endoscopic treatment options: Z-POEM (Zenker peroral endoscopic myotomy), endoscopic stapler diverticulotomy, endoscopic laser septum division. Surgical treatment: diverticulectomy + cricopharyngeal myotomy (open or transcervical). Conservative follow-up is sufficient for asymptomatic small diverticula. Aspiration pneumonia and SCC development (0.3-0.5%) are complications. Barium esophagram should be performed before endoscopy to evaluate diverticulum size, neck structure, and anatomical relationships.
Symptomatic Zenker diverticulum is treated with surgical or endoscopic cricopharyngeal myotomy. Endoscopic stapler diverticulotomy is a minimally invasive alternative. Treatment is recommended due to aspiration pneumonia risk. SCC development risk is very low (0.3-0.4%).