BACKGROUND
{mosimage}On physical examination, the patient’s vital signs are within the normal range. The examination of the oropharynx yields unremarkable findings. The patient has no neck mass or other abnormality. Examination of the thorax and the abdomen also yield unremarkable results.
A barium-swallow study is performed. Two images from this study are shown (see Images 1-2).
What is the diagnosis?
HINT
Observe the saclike structure in the esophagus.
Authors:
Pramod Gupta, MD, Staff Physician, Department of Radiology, Dallas VA Medical Center, Dallas, Texas
Jitendra Gohil, MD, Staff Physician, Department of Radiology, Dallas VA Medical Center, Dallas, Texas
eMedicine Editor:
Rick G. Kulkarni, MD, FACEP, Assistant Professor, Yale School of Medicine, Section of Emergency Medicine, Department of Surgery, Attending Physician, Medical Director, Department of Emergency Services, Yale-New Haven Hospital, CT
ANSWER
Zenker (pharyngoesophageal) diverticulum: The frontal (see Image 1) and lateral (see Image 2) barium-swallow images of the upper esophagus demonstrate a large outpouching at the posterior aspect of the pharyngoesophageal junction that retains barium (arrows). This finding is consistent with a Zenker diverticulum.
{mosimage}A Zenker diverticulum, also called a pharyngoesophageal diverticulum, is a pseudodiverticulum consisting of esophageal mucosa and submucosa that herniate posteriorly between the cricopharyngeus and the inferior pharyngeal constrictor muscles and through an area of potential weakness referred to as the Killian dehiscence. The pathogenesis of this condition is not well known. Patients with a Zenker diverticulum are thought to have a discoordination of the swallowing mechanism that increases pressure on the mucosa of the pharynx. Over time, this pressure leads to herniation of the esophageal mucosa through the Killian dehiscence.
The condition occurs most commonly in elderly women, with peak incidence in the seventh to ninth decades of life. The most common presenting feature in a Zenker diverticulum is upper-esophageal dysphagia, which occurs in as many as 98% of patients. Other common symptoms are halitosis, regurgitation of undigested food, aspiration, noisy deglutition, and changes in voice (eg, hoarseness). Weight loss, possibly resulting from limited caloric intake and recurrent pulmonary infection from aspiration, occurs in approximately one third of patients.
In patients with a Zenker diverticulum, the physical findings are usually normal. Fluoroscopic barium-swallow studies are the mainstay of diagnosis and demonstrate the characteristic outpouching that arises from the midline of the posterior wall of the distal pharynx near the pharyngoesophageal junction. This finding is best identified during swallowing, and it is typically seen on lateral images, on which the diverticulum is observed at the C5-C6 vertebral level. If the diverticulum is large, it may protrude laterally, most often to the left side. After the bolus of contrast agent passes the upper esophagus, the diverticulum is typically seen extending posterior to the cricopharyngeus muscle, and the contrast material that was retained in the diverticulum may be regurgitated into the hypopharynx. The lumen of the diverticulum should be carefully observed for irregularities or filling defects because squamous cell carcinoma can develop in a small percentage of cases.
When incidentally imaged on computed tomography (CT) scans or magnetic resonance imaging (MRI) scans, a Zenker diverticulum appears as a structure that arises posteriorly from the hypopharynx and is filled with air, fluid, or oral contrast material. Zenker diverticula may also be found on endoscopy. Care must be taken during endoscopic procedures, because passage of the endoscope into the diverticulum may result in perforation.
Small, asymptomatic diverticula may be followed up by monitoring the progression of symptoms. Surgical management should be considered in patients with clinically significant dysphagia, weight loss, pulmonary aspiration with recurrent lung infections, and complications related to bleeding. Surgical options for treatment include myotomy of the cricopharyngeus muscle, with or without diverticulopexy, and endoscopic division of diverticular wall with stapling. The success rate (ie, the relief of symptoms as measured in most studies) is approximately 93%.
References:
1. Dahnert W. Radiology Review Manual. 4th ed. Baltimore, Md: Lippincott, Williams and Wilkins; 1999:720.
2. Ellis FH Jr. Pharyngoesophageal (Zenker’s) diverticulum. Adv Surg 1995;28:171-89. [MEDLINE: 7879678]
3. Gonzalez F, Arnaiz J, Landeras R, et al. A giant Zenker’s diverticulum: an uncommon cause of severe dysphagia [European Society of Radiology Web site]. Case 3047. Last updated: September 16, 2005. Available at: www.eurorad.org/case.php?id=3047. Accessed January 17, 2006.
4. Sutherland MJ, Peyton BD. Zenker Diverticulum. eMedicine Journal [serial online]. Last update: January 5, 2006. Available at: www.emedicine.com/med/topic2777.htm. Date Accessed: January 17, 2006.
