Schatzki ring is a benign, thin, circular mucosal and submucosal membrane seen at the squamocolumnar junction of the distal esophagus that does not contain muscularis propria.[1]
Since the 1950s, several investigators have published reports of patients with dysphagia who had associated lower esophageal ringlike constrictions, but each investigator had a different opinion as to the cause and nature of these rings. In 1953, Ingelfinger and Kramer believed that these rings occurred as a result of a contraction by an overactive band of esophageal muscle[2] ; however, Schatzki and Gary believed that these rings were fixed and not contractile.[3] Some of this controversy may be related to the confusion of categorizing muscular and mucosal rings under the same entity, as concluded by Goyal et al.[4, 5, 6, 7]
See the image below.
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Schatzki Ring. Endoscopic appearance of the distal esophagus illustrating a Schatzki ring.
Two rings have been identified in the distal esophagus. The muscular ring, or A ring, is a thickened symmetric band of muscle that forms the upper border of the esophageal vestibule and is located approximately 2 cm above the gastroesophageal junction. The A ring is rare; furthermore, it is even more rarely associated with dysphagia. On the other hand, the mucosal ring, or B ring, is quite common and is the subject of discussion in this article. The B ring is a diaphragmlike thin mucosal ring usually located at the squamocolumnar junction; it may be symptomatic or asymptomatic, depending on the luminal diameter.
The pathogenesis is not clear, and patients typically present with intermittent nonprogressive dysphagia for solids. Fortunately, most patients respond well to initial and repeat dilatation therapy. A small number of patients may have stubborn rings that require more aggressive endoscopic or surgical intervention.
The pathogenesis of Schatzki rings is not clear, and at least four hypotheses have been proposed. These hypotheses may not be mutually exclusive. Proposed hypotheses are as follows:
The ring is a pleat of redundant mucosa that forms when the esophagus shortens transiently or permanently for unknown reasons.
The ring is congenital in origin.
The ring is actually a short peptic stricture occurring as a consequence of gastroesophageal reflux disease.
The ring is a consequence of pill-induced esophagitis.
Data supporting or refuting the first two hypotheses are few.
Data about the association of gastroesophageal reflux disease and rings are inconclusive or contradictory. It has been hypothesized that the ring acts as a protective barrier against further reflux. However, in one study involving 20 patients, no significant differences were noted in any of the reflux parameters measured before and after dilation. In fact, it was interesting to note that thick rings may actually decrease esophageal acid clearance, especially in the supine position, thereby increasing esophageal acid exposure.[8]
The last hypothesis was based on a chance observation in one study showing that 62% of patients with rings had ingested medications known to cause pill-induced esophagitis.[9]
In some studies, the severity of symptoms has clearly been demonstrated to correlate with the luminal diameter. Dysphagia predictably occurs in patients with a luminal diameter less than 13 mm and may vary between 13-20 mm, depending on the size and type of bolus.
Schatzki ring is quite common and may be found in between 6% and 14% of all patients undergoing routine barium swallow studies; however, few of these patients exhibit any symptoms of dysphagia.[1] No known population studies exist for its prevalence in the general population.[1]
In retrospective review (2003-2018) of esophageal foreign body impaction (EFBI) at a single US institution, investigators analyzing data from 204 patients found structural causes were the most common etiology, with benign strictures and stenosis in 21.5% of patients, followed by Schatzki ring (7.8%) and hiatal hernia (6.9%).[10]
International data
In a 2014 cross-sectional study (2012-2013) of data from 139 Pakistani patients presenting with dysphagia who underwent endoscopy, Schatzki ring was the fourth most common finding (n = 14 [10.1%]) after malignant esophageal stricture (n = 38 [27.3%]), normal upper gastrointestinal endoscopy (n =29 [20.9%]), and reflux esophagitis (n = 25 [18.0%]).[11]
In a 2015 retrospective report (1994-2004) of 91 geriatric (aged 62-92 years) Israeli patients presenting with dyspepsia who underwent standard radiographic studies and provocation tests for gastroesophageal reflux disease (GERD), Schatzki ring was present in 20 of the patients (22%), with all of the rings (100%) at the level of the proximal sphincter.[12]
Race-, sex-, and age-related demographics
No known race or sex predilection exists.
Although no known predilection for a specific age group exists, most patients are older than 40 years at presentation. It is relatively rare in children.[13]
In a retrospective study (2000-2009) that included 18,668 gastrointestinal or esophageal imaging studies in 15,410 children and young adults, Towbin and Diniz found 25 patients (0.2%) with a confirmed diagnosis of Schatzki ring.[13] Hiatal hernia (n = 24/25; 96%), eosinophilic esophagitis (n = 10/25; 40%), and gastroesophageal reflux (n = 10/25; 40%) were commonly associated with Schatzki rings. The investigators suggested clinicians consider endoscopy and biopsy in all children with Schatzki ring owing to the relatively high incidence of eosinophilic esophagitis in their analysis.[13]
Although results of dilatation are excellent for Schatzki ring, some series report that patients frequently have recurrence of dysphagia. In one study of 33 patients, 32% had recurrence at 1 year, and 89% had recurrence at 5 years.[14] Recurrence rates up to 64% in the first 2 years have also been reported.[1]
No known prognostic indicators for recurrence of dysphagia exist, except for associated gastroesophageal reflux disease as reported in some studies. Other studies have refuted this contention.
Reassure patients that the ring is a benign entity; however, prepare them for repeat dilatation in the event of recurrence of dysphagia.
Morbidity/mortality
No mortality has been ascribed to this entity.
Morbidity is variable. Most episodes of dysphagia are short lived, and intervening periods between episodes may vary from weeks to months or even to years.
Complications
Esophageal dilatation for esophageal rings is well established as a safe procedure based on published series; however, potential complications include perforation and bleeding.
Most patients with Schatzki ring are asymptomatic. Of those who have symptoms, most present with intermittent, episodic, nonprogressive dysphagia to solids.[1] Dysphagia to liquids is usually not present. Note the following:
The episode of dysphagia appears to be short lived.
Typically, the patient ate a meal in a hurried fashion.
The bolus of food may occasionally be forced down by drinking liquids, or may be regurgitated to relieve the obstruction.
After forcing the bolus through or regurgitating it, the patient can usually finish his or her meal without difficulty.
Dysphagia may not recur for months or years in these patients. Daily dysphagia is unlikely to be caused by a Schatzki ring.
Patients often present after rapidly eating meat and drinking alcohol at a restaurant; hence, some authorities equate Schatzki ring to the "steakhouse syndrome." Bread (especially freshly baked) and meat ("steakhouse syndrome") appear to be common foods that frequently precipitate symptoms.
Associated symptoms of heartburn and regurgitation characteristic of gastroesophageal reflux disease may occur in some patients.
Physical examination
Physical examination findings are usually unremarkable in patients with Schatzki ring.
The patient may salivate and drool if the offending food bolus continues to completely obstruct the lower esophagus for a longer duration, but this scenario is excessively rare.
Perform a prone full-column barium esophagram as the initial study because it is more sensitive than double-contrast radiography or endoscopy, especially when the luminal diameter is more than 10 mm. (See the following images.) Distending the lower esophagus by performing the Valsalva maneuver enhances sensitivity. The sensitivity may be further improved by using a barium tablet or a coated marshmallow.
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Schatzki Ring. Endoscopic appearance of the distal esophagus illustrating a Schatzki ring.
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Schatzki Ring. Barium swallow illustrating an indentation at the gastroesophageal junction consistent with a Schatzki ring above a sliding hiatal hern....
Endoscopy
Findings differ significantly by sex, age, and procedure. The most common findings in one study were stricture, normal results, esophagitis/ulcer, Schatzki ring, esophageal food impaction, and suspected malignancy.[16]
Abdominal compression during endoscopy (Bolster technique) can increase the detection rate of Schatzki rings during endoscopy.[17]
Although barium studies are performed initially for suspected Schatzki ring, EGD is performed subsequently to confirm the diagnosis and to exclude any other diagnosis.
Endoscopic examination evaluates the mucosa of the distal esophagus, confirming the diagnosis of concomitant gastroesophageal reflux disease or a short peptic stricture instead of a ring.
The upper surface of a Schatzki ring is covered by squamous epithelium, and the lower surface is covered by columnar epithelium because the ring is usually located at the squamocolumnar junction. The ring is composed of the mucosa and submucosa and does not contain the muscularis propria. Occasionally, the lamina propria may contain fibrous tissue.
Treatment is aimed at reducing the diameter of the Schatzki ring.[1]
Using a large French mercury bougie, polyvinyl bougie, or a balloon, esophageal dilatation is used with the intention of fracturing the ring—not merely stretching it. Note the following:
After initial dilatation, aggressively treat any associated reflux disease. In one prospective, randomized, placebo-controlled study involving 44 consecutive patients, acid suppressive maintenance therapy with omeprazole after bougienage was shown to prevent relapse of the ring as compared to the placebo group. The duration of follow-up was about 60 months, and the mean duration of relapse was 19.9 months.[18]
Subsequent dilatations may be needed for recurrence of dysphagia. Determine the need for such dilatations on an individual basis. However, in one study involving only 11 patients, objective measurements with a 12.7-mm barium pill showed that the pill failed to pass the ring in 60% of patients at 1 month and 100% of patients at 1 year. This suggests that recurrence of dysphagia is not a reliable indicator of relapse or persistence of the ring.[19]
If dysphagia persists or recurs shortly after dilatation, consider an esophageal manometry study to look for any treatable motility disorder.
If the manometry does not reveal any treatable motility disorder, consider repeating an upper endoscopy to assure healing of esophagitis or to confirm persistence of the ring.
Rees et al performed a retrospective study of all patients (N = 38; 54 procedures) undergoing transnasal balloon dilation of the esophagus at two tertiary care centers to determine the safety of this procedure.[20] The investigators determined that low complication rates are associated with transnasal esophageal balloon dilation in nonsedated or sedated patients, with a 96% well tolerance rate.[20]
Based on anecdotal reports, larger pneumatic balloons, such as balloons used for achalasia dilatation, may be considered if the ring persists despite two or more bougie dilatations. Fortunately, this measure is rarely required. Use larger balloons with extreme caution because of the increased risk of perforation.
Successful endoscopic electrocautery incision using a needle-knife papillotome has been reported and may be considered. A randomized, controlled trial compared 52-Fr Maloney dilator versus four quadrant biopsy of the ring and found that both modalities were equally effective in relieving dysphagia at 3 months and at 12 months in 26 patients. However, 100% of the biopsy group described the procedure as easy as opposed to 55% of the dilation group.[21]
Consultations
On very rare occasions, surgical excision may be needed if medical therapy fails. Antireflux surgery may also be considered at the same time for concomitant gastroesophageal reflux disease.
Diet and activity
No major dietary restrictions or activity restriction are applicable. The patient may be advised to avoid eating quickly and to chew his or her food well, especially meat and bread; however, whether this advice is truly beneficial is unclear.
On very rare occasions, one may have to resort to surgical excision if medical therapy fails. Antireflux surgery may also be considered at the same time for concomitant gastroesophageal reflux disease.
Surgical approaches have included bougies, balloons, biopsies, and diathermic monopolar incision.[22] Unfortunately, recurrence is common over time.
In a randomized, prospective trial, Wills et al compared the efficacy of bougie dilation (n = 25) with electrosurgical incision (n = 25) of symptomatic Schatzki rings at 1-year follow-up in the presence of acid suppression with rabeprazole treatment.[23] The investigators found electrosurgical incision of Schatzki rings to be a safe procedure that provided a longer duration of symptom improvement (7.99 mo) relative to bougie dilation (5.86 mo) (P = 0.03). Gastroesophageal reflux disease scores in both groups were significantly improved with the addition of rabeprazole therapy.[23]
Successful complete excision of symptomatic Schatzki ring with the use of jumbo cold biopsy forceps has been reported.[20] Gonzalez et al revealed that all 10 patients with dysphagia as a result of a Schatzki ring in their observational study (mean follow-up, 376 days) achieved complete endoscopic obliteration of their Schatzki rings with cold jumbo biopsy forceps. Six of 10 patients had been previously treated with bougienage or balloon dilation, 5 patients were on proton pump inhibitor maintenance therapy, and 1 patient was on H2 blocker maintenance therapy. No serious complications were noted.[20]
No specific drug therapy for Schatzki ring exists. If reflux disease is suspected based on symptoms or endoscopic findings, consider treating with potent antisecretory agents (eg, proton pump inhibitors) in addition to antireflux precautions.
Clinical Context:
Decreases gastric acid secretion by inhibiting the parietal cell H+/K+ ATP pump. For short-term (4-8 wk) treatment and relief symptomatic erosive or ulcerative GERD. Patients not healed after 8 wk, consider additional 8-wk course.
Clinical Context:
S-isomer of omeprazole. Inhibits gastric acid secretion by inhibiting H+/K+ -ATPase enzyme system at secretory surface of gastric parietal cells.
Clinical Context:
Suppresses gastric acid secretion by specifically inhibiting H+/K+ ATPase enzyme system at the secretory surface of gastric parietal cells.
Inhibits H+/K+ -ATPase enzyme system in the gastric parietal cells, resulting in decreased gastric acid secretion. Used for esophagitis or unresponsiveness to H2-antagonist therapy.
Rajeev Vasudeva, MD, Clinical Professor of Medicine, Consultants in Gastroenterology, University of South Carolina School of Medicine
Disclosure: Received honoraria from Pricara for speaking and teaching; Received consulting fee from UCB for consulting.
Specialty Editors
Francisco Talavera, PharmD, PhD, Adjunct Assistant Professor, University of Nebraska Medical Center College of Pharmacy; Editor-in-Chief, Medscape Drug Reference
Disclosure: Received salary from Medscape for employment. for: Medscape.
Chief Editor
Praveen K Roy, MD, MSc, Clinical Assistant Professor of Medicine, University of New Mexico School of Medicine
Disclosure: Nothing to disclose.
Acknowledgements
Mounzer Al Samman, MD Assistant Professor, Department of Internal Medicine, Division of Gastroenterology, Texas Tech University School of Medicine
Mounzer Al Al Samman, MD is a member of the following medical societies: American College of Gastroenterology, American College of Physicians, and American Gastroenterological Association
Disclosure: Nothing to disclose.
John Schaberg, MD
Disclosure: Nothing to disclose.
Noel Williams, MD Professor Emeritus, Department of Medicine, Dalhousie University, Halifax, Nova Scotia, Canada; Professor, Department of Internal Medicine, Division of Gastroenterology, University of Alberta, Edmonton, Alberta, Canada
Noel Williams, MD is a member of the following medical societies: Royal College of Physicians and Surgeons of Canada
Schatzki Ring. Endoscopic appearance of the distal esophagus illustrating a Schatzki ring.
Schatzki Ring. Endoscopic appearance of the distal esophagus illustrating a Schatzki ring.
Schatzki Ring. Barium swallow illustrating an indentation at the gastroesophageal junction consistent with a Schatzki ring above a sliding hiatal hernia.
Schatzki Ring. Endoscopic appearance of the distal esophagus illustrating a Schatzki ring.
Schatzki Ring. Barium swallow illustrating an indentation at the gastroesophageal junction consistent with a Schatzki ring above a sliding hiatal hernia.
Schatzki Ring. A Schatzki ring dilated by the passage of a single large bougie.
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