A physician-validated, board-style question from the Active Transport QBank. Try it, then check the reasoning for every option.
A 68-year-old man presents to the office with his wife complaining of difficulty in swallowing, which progressively worsened over the past month. He has difficulty in initiating swallowing and often has to drink water with solid foods. He has no problems swallowing liquids. His wife is concerned about her husband’s bad breath. Adding to his wife, the patient mentions a recent episode of vomiting where the vomit smelled ‘really bad’ and contained the food that he ate 2 days before. On examination, the patient’s blood pressure is 110/70 mm Hg, pulse rate is 72/min, with normal bowel sounds, and no abdominal tenderness to palpation. A barium swallow radiograph is taken which reveals a localized collection of contrast material in the cervical region suggestive of an outpouching. Which of the following statements best describes the lesion seen on the radiograph?
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A
Persistence of an embryologic structureIncorrect. Persistence of an embryologic structure describes Meckel's diverticulum (vitelline duct remnant), not the acquired pulsion outpouching of Zenker.
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B
Outpouching of all 3 layers of the esophageal mucosal tissue distal to the upper esophageal sphincterIncorrect. All three layers describes a TRUE diverticulum (e.g., traction or epiphrenic); Zenker is a false diverticulum involving only mucosa and submucosa.
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C
Increased pressure above the upper esophageal sphincter resulting in a defect in the wallCorrect. Zenker is a pulsion (false) diverticulum from increased pressure above the upper esophageal sphincter, herniating through Killian's triangle.
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D
Failure of neural crest migration into the Auerbach plexusIncorrect. Failure of neural crest migration into the Auerbach plexus describes Hirschsprung disease or achalasia, not Zenker diverticulum.
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E
Eosinophilic infiltration of the esophageal mucosa with concentric rings on endoscopyIncorrect. This describes eosinophilic esophagitis, which causes dysphagia and food impaction but produces trachealization rather than an outpouching of contrast in the cervical region.
↑ Tap an answer to reveal the reasoning
Answer: C. An elderly man with progressive dysphagia for solids, halitosis, regurgitation of undigested food eaten days earlier, and a barium-swallow outpouching in the cervical region has a Zenker diverticulum. Zenker is a FALSE diverticulum (pulsion type) — it herniates only mucosa and submucosa through Killian's triangle, an area of muscular weakness between the oblique fibers of the thyropharyngeus and the transverse fibers of the cricopharyngeus muscle of the inferior pharyngeal constrictor. Increased intraluminal pressure above a dysfunctional upper esophageal sphincter (cricopharyngeus) drives the mucosal outpouching.
Because it lacks all three muscle layers, Zenker is a false diverticulum — distinguishing it from true diverticula like Meckel diverticulum. The food trapped in the pouch produces the characteristic halitosis and regurgitation of days-old food. Treatment is cricopharyngeal myotomy (open or endoscopic), often with diverticulectomy or diverticulopexy for larger pouches.
Pearl: never blindly pass an NG tube in suspected Zenker — risk of pouch perforation. Persistence of an embryologic structure (option A) describes Meckel's; failure of neural crest migration describes Hirschsprung; outpouching of all three layers describes a true diverticulum (e.g., epiphrenic or traction diverticula).
**Why each option:**
**A.** Persistence of an embryologic structure describes Meckel's diverticulum (vitelline duct remnant), not the acquired pulsion outpouching of Zenker.
**B.** All three layers describes a TRUE diverticulum (e.g., traction or epiphrenic); Zenker is a false diverticulum involving only mucosa and submucosa.
**C.** Correct. Zenker is a pulsion (false) diverticulum from increased pressure above the upper esophageal sphincter, herniating through Killian's triangle.
**D.** Failure of neural crest migration into the Auerbach plexus describes Hirschsprung disease or achalasia, not Zenker diverticulum.