| Patient Education |
|
Click here for patient education.
|
|
You are in: eMedicine Specialties >
Radiology > GASTROINTESTINAL
Schatzki Ring
Article Last Updated: Apr 14, 2003
AUTHOR AND EDITOR INFORMATION
Section 1 of 7  
Author: Arastoo Vossough, MD, PhD, Staff Physician, Department of Radiology, Hospital of the University of Pennsylvania
Arastoo Vossough is a member of the following medical societies: American Roentgen Ray Society and Radiological Society of North America
Coauthor(s):
Stephen E Rubesin, MD, Professor, Department of Radiology, University of Pennsylvania School of Medicine
Editors: John L Haddad, MD, Clinical Associate Professor, Department of Radiology, Weill Medical College of Cornell University; Director of Body MRI, Department of Radiology, Methodist Hospital in Houston; Bernard D Coombs, MB, ChB, PhD, Consulting Staff, Department of Specialist Rehabilitation Services, Hutt Valley District Health Board, New Zealand; Udo P Schmiedl, MD, PhD, Clinical Professor, Department of Radiology, University of Washington; Consulting Staff, Swedish Medical Center, University of Washington Medical Center, Seattle Radiologists; Robert M Krasny, MD, Consulting Staff, Department of Radiology, The Angeles Clinic and Research Institute; Eugene C Lin, MD, Consulting Staff, Department of Radiology, Virginia Mason Medical Center
Author and Editor Disclosure
Synonyms and related keywords:
lower esophageal mucosal ring, mucosal ring, B ring, steakhouse syndrome, intermittent dysphagia, acute food impaction, steakhouse syndrome
Background
Lower esophageal rings were described first by Templeton in 1944. The vast majority of patients with lower esophageal rings are asymptomatic. The association of intermittent dysphagia with lower esophageal rings was reported by Ingelfinger and Kramer and also by Schatzki and Gray in 1953. The term Schatzki ring is reserved for a lower esophageal mucosal ring that causes intermittent dysphagia. Thus, the diagnosis of a Schatzki ring is based on both clinical and radiologic findings.
Pathophysiology
A Schatzki ring is a ring composed of mucosa and submucosa located at the esophagogastric junction. Histologically, the superior surface of the ring is stratified squamous epithelium (ie, esophageal mucosa), and the inferior surface of the ring is covered by columnar epithelium (ie, gastric mucosa).
The exact pathogenesis of lower esophageal rings is not known. Both congenital and acquired origins have been proposed for Schatzki rings. The data are not completely conclusive, but the bulk of the evidence indicates an acquired etiology. Many patients do not have symptoms before the age of 50 years; hence, a congenital origin is unlikely. Most investigators believe that a Schatzki ring is an annular ringlike stricture caused by scarring as a result of reflux esophagitis.
Other investigators have demonstrated that Schatzki rings become narrowed during serial radiographic examinations and that they transform into actual peptic strictures. Even so, endoscopic biopsy and 24-hour esophageal pH monitoring have failed to show any symptoms or signs of gastroesophageal reflux or reflux esophagitis in more than one third of patients with Schatzki rings.
Different investigators have proposed that vagal stimulation causes longitudinal muscle contraction and foreshortening of the esophagus with mucosal infolding at the esophagogastric junction. This structure undergoes fibrosis and scarring in some patients, leading to the development of Schatzki rings.
The luminal diameter of the mucosal ring is the primary factor that determines the presence or absence of dysphagia. In 1963, Schatzki reported that if the luminal diameter of a lower esophageal mucosal ring is 13 mm or less, patients regularly experience intermittent dysphagia to solid food. If the luminal diameter is greater than 20 mm, patients are usually asymptomatic. Luminal diameters of 13-20 mm cause variable degrees of dysphagia, depending on the type and size of the food bolus.
Frequency
United States
Lower esophageal rings have been found during 6-14% of all routine upper gastrointestinal barium examinations, but the vast majority of the patients are asymptomatic. Lower esophageal rings that cause symptoms (true Schatzki rings) occur only in 0.5% of patients undergoing these examinations. Schatzki rings are a common cause of intermittent dysphagia.
Mortality/Morbidity
- No direct mortality is associated with Schatzki rings.
- The primary morbidities associated with Schatzki rings are intermittent dysphagia and occasional acute food impaction. One case of esophageal rupture secondary to food impaction has been reported in a patient with a Schatzki ring.
Race
Schatzki rings are seen in all races, and no racial predominance has been reported.
Sex
No increased prevalence of Schatzki rings has been reported in either sex.
Age
Although Schatzki rings have been reported in newborns and young children, most cases occur in middle-aged or older adults.
Anatomy
By definition, lower esophageal mucosal rings occur at the anatomic esophagogastric junction or B ring. The mucosa above the ring is squamous, and the mucosa below the ring is columnar, corresponding to the esophagogastric junction. Only symptomatic lower esophageal mucosal rings that cause dysphagia are termed Schatzki rings.
Clinical Details
The cardinal manifestation of Schatzki rings is intermittent dysphagia for solid foods. Patients also may present with acute food impaction causing an obstruction in the esophagus. These patients have acute substernal chest pain or, alternatively, a sense of something stuck in the lower chest. Most commonly, a large piece of meat is stuck at the level of the ring, hence the term steakhouse syndrome. If the patient passes or regurgitates the food bolus, the symptoms resolve. One case of esophageal perforation related to food bolus impaction due to a Schatzki ring was reported.
Preferred Examination
Barium esophagography is the preferred method of detection of Schatzki rings. Single-contrast esophagography performed with the patient drinking in the prone position is more sensitive in detecting lower esophageal mucosal rings than is erect double-contrast imaging of the esophagus.
Upper gastrointestinal endoscopy is not as sensitive as barium esophagography in detecting lower esophageal rings. In one study, endoscopy failed to depict more than one third of radiologically demonstrated lower esophageal rings, half of which had caused symptoms and dysphagia.
Limitations of Techniques
Esophageal rings may be missed during barium esophagography if distention of the distal esophagus is inadequate; therefore, adequate distention of the esophagus during barium esophagography is imperative. This distention is best achieved by using a single-contrast technique in the prone or right or left anterior oblique position with large boluses of barium. A modified Valsalva maneuver also may help in demonstrating the ring by distending the associated hiatal hernia.
Esophagus, Carcinoma
Other Problems to be Considered
Annular peptic strictures
Muscular rings
Esophageal webs
Findings
On barium esophagography, lower esophageal mucosal rings are manifested by a thin circumferential constriction at the gastroesophageal junction. These rings almost always are associated with a sliding hiatal hernia. The ring itself has smooth symmetric margins and is only 2-4 mm in height (see Image 1). Like all esophageal rings and strictures, the lumen of the esophagus has to be dilated beyond the caliber of the ring if the ring is to be visualized; therefore, adequate distention of the distal esophagus is of paramount importance and is achieved best by using single-contrast, prone examinations (see Image 2). A barium pill of known diameter (eg, 12 mm) may be used at the end of the examination to determine the functional luminal caliber of the ring. Most symptomatic rings (true Schatzki rings) are 13 mm or less in caliber.
Degree of Confidence
The finding of a fixed, smooth, narrow, circumferential ring at the esophagogastric junction in a patient with dysphagia is virtually diagnostic of a Schatzki ring.
False Positives/Negatives
The distal esophagus may be narrowed by a ringlike peptic stricture, lower esophageal mucosal ring (A ring), focal esophageal cancer, or an esophageal web, as well as by a Schatzki ring.
Focal annular peptic strictures are usually asymmetric, and they often have a vertical thickness greater than 5 mm. Lower esophageal muscular rings, also termed contractile rings or A rings, are a normal area of contraction in the distal esophagus located a few centimeters above the gastroesophageal junction. These should not be confused with Schatzki rings.
In contrast to Schatzki rings, which are fixed anatomic mucosal structures, lower esophageal muscular rings are transient, smooth, thick, circumferential indentations in the esophagus. If observed long enough during the course of the examination, these muscular rings will relax and disappear.
A patient may have both a mucosal ring at the gastroesophageal junction and a muscular ring a few centimeters more proximal.
A focal carcinoma of the lower esophagus should not be confused with a mucosal ring. In contrast to Schatzki rings, esophageal cancers have an irregular contour, they are asymmetric, and they have shelflike borders within the narrowed segment. These features help distinguish them from true mucosal rings.
Uncommonly, esophageal webs can be circumferential and resemble a mucosal ring, but they are most commonly found in the cervical esophagus. Rarely, esophageal webs can be found in the distal esophagus, but these webs are located above the gastroesophageal junction; therefore, they can be differentiated from lower esophageal mucosal rings. More often than not, esophageal webs do not produce a complete circumferential ring and only appear as a thin indentation on one side of the esophagus.
Patients with asymptomatic lower esophageal rings do not require any intervention or treatment. In mild cases of symptomatic rings (true Schatzki rings), advising patients to chew their food adequately and eat more slowly is all that may be needed. In more severe cases, mechanical bougienage of the ring may be performed, usually with a Maloney dilator.
Other methods used for treatment of Schatzki rings include pneumatic balloon dilatation with an achalasia balloon, electrocautery incision of the ring, 4-quadrant biopsy of the ring, the placement of radial ring incisions by using a sphincterotome, Nd:YAG laser incision of the ring, and open surgery through a gastrostomy opening.
Long-term results of treatment are variable. However, in almost all instances, a high recurrence rate has been reported after the endoscopic treatment of Schatzki rings. In one series, approximately one third of patients had recurrent symptoms at 1 year, and only 11% were symptom free at 5 years after a single dilation. In the long run, a large percentage of patients eventually require multiple attempts at dilating the ring.
| Media file 1:
Schatzki ring on an erect double-contrast barium esophagogram. Image demonstrates a thin ringlike narrowing (arrows) in the lower esophagus just above a hiatal hernia. |
 |  View Full Size Image | |
Media type: X-RAY
|
| Media file 2:
Schatzki ring. Prone single-contrast barium esophagogram demonstrating a thin, ringlike narrowing (arrows) in the lower esophagus just above a hiatal hernia. This view is most sensitive for detecting lower esophageal rings, provided adequate esophageal distention is achieved. |
 | View Full Size Image | |
Media type: X-RAY
|
- Buckley K, Buonomo C, Husain K, Nurko S. Schatzki ring in children and young adults: clinical and radiologic findings. Pediatr Radiol. Nov 1998;28(11):884-6. [Medline].
- Chotiprasidhi P, Minocha A. Effectiveness of single dilation with Maloney dilator versus endoscopic rupture of Schatzki''s ring using biopsy forceps. Dig Dis Sci. Feb 2000;45(2):281-4. [Medline].
- DeVault KR. Lower esophageal (Schatzki''s) ring: pathogenesis, diagnosis and therapy. Dig Dis. Sep-Oct 1996;14(5):323-9. [Medline].
- Eckardt V, Dagradi AE, Stempien SJ. The esophagogastric (Schatzki) ring and reflux esophagitis. Am J Gastroenterol. Nov 1972;58(5):525-30. [Medline].
- Gore RM, Levine MS. Textbook of Gastrointestinal Radiology. Philadelphia: WB Saunders Co;2000:487-8.
- Groskreutz JL, Kim CH. Schatzki''s ring: long-term results following dilation. Gastrointest Endosc. Sep-Oct 1990;36(5):479-81. [Medline].
- Guelrud M, Villasmil L, Mendez R. Late results in patients with Schatzki ring treated by endoscopic electrosurgical incision of the ring. Gastrointest Endosc. Apr 1987;33(2):96-8. [Medline].
- Hendrix TR. Schatzki ring, epithelial junction, and hiatal hernia--an unresolved controversy. Gastroenterology. Sep 1980;79(3):584-5. [Medline].
- Ingelfinger FJ, Kramer P. Dysphagia produced by a contractile ring in the lower esophagus. Gastroenterology. 1953;23:419.
- Jamieson J, Hinder RA, DeMeester TR, et al. Analysis of thirty-two patients with Schatzki''s ring. Am J Surg. Dec 1989;158(6):563-6. [Medline].
- Johnson AC, Lester PD, Johnson S, et al. Esophagogastric ring: why and when we see it, and what it implies: a radiologic-pathologic correlation. South Med J. Oct 1992;85(10):946-52. [Medline].
- Klein MD, Waltner J, Ball W, Kosloske AM. Schatzki ring in a newborn. Pediatrics. Dec 1981;68(6):884-5. [Medline].
- Lam CR, Taber RE, Arciniegas E. The nature and surgical treatment of lower esophageal ring (Schatzki''s ring). J Thorac Cardiovasc Surg. Jan 1972;63(1):34-40. [Medline].
- Marshall JB, Kretschmar JM, Diaz-Arias AA. Gastroesophageal reflux as a pathogenic factor in the development of symptomatic lower esophageal rings. Arch Intern Med. Aug 1990;150(8):1669-72. [Medline].
- Miller S, Hines C Jr, Ochsner JL. Spontaneous perforation of the esophagus associated with a lower esophageal ring. Am J Gastroenterol. Dec 1988;83(12):1405-8. [Medline].
- Ottinger LW, Wilkins EW Jr. Late results in patients with Schatzki rings undergoing destruction of the ring and hiatus herniorrhaphy. Am J Surg. Apr 1980;139(4):591-4. [Medline].
- Rohrmann CA Jr. When is a Schatzki ring clinically significant, and what is the best maneuver to demonstrate it on barium swallow? Does the abnormality progress if it is not treated?. AJR Am J Roentgenol. Jul 1994;163(1):215. [Medline].
- Schatzki R, Gary JE. Dysphagia due to a diaphragm-like localized narrowing in the distal esophagus ("lower esophageal ring"). AJR Am J Roentgenol. 1953;70:911.
- Schatzki R. The lower esophageal ring: Long-term follow-up of symptomatic and asymptomatic rings. AJR Am J Roentgenol. 1963;90:805.
- Scolapio JS, Pasha TM, Gostout CJ, et al. A randomized prospective study comparing rigid to balloon dilators for benign esophageal strictures and rings. Gastrointest Endosc. Jul 1999;50(1):13-7. [Medline].
- Yamada T, Alpers DH, Owyang C. Textbook of Gastroenterology. Lippincott-Raven;1995:1166-7.
Schatzki Ring excerpt Article Last Updated: Apr 14, 2003
|
