Schatzki's ring : an obscure cause of dysphagia (a case report).
The differential diagnosis of dysphagia must include consideration of the lower oesophagus ring. It was first described in 1953 by Schatzki and Gary as a constant, symmetrical diaphragm-like, narrowing in the lower oesophagus just above the diaphragm. This ring-like narrowing occurs at the junction of the oesophagus and gastric mucosa in association with a small sliding hiatus hernia.
A 16 year old male, came with complaints of progressive dysphagia over a period of 6 months. Dysphagia was more for solids than liquids and episodic in nature, with varying intervals of freedom from symptoms.
Barium swallow showed concentric, smooth, ring-like narrowing in the lower oesophagus, constant in position. [Fig. 1] Oesophagus above the ring was normal. Oesophagoscopy showed a narrowing at 34 cm distance from the incisor. There were no ulcers or scars and passage of scope into the stomach was easy.
As there were no features suggestive of reflux oesophagitis, the patient was subjected to repeated oesophageal dilatation over a period of three weeks. The ring was gradually dilated from 20F to 40F size. The patient has remained asymptomatic after 9 months of dilatation.
Postlethwait and Sealy defined the following criteria for the diagnosis of lower oesophageal web or Schatzki's ring:
(1) A sliding hiatus hernia must be present.
(2) The web is always present on repeated roentgenographic examinations.
(3) The lumen of the web does not increase in size during repeated studies.
(4) On swallowing a bolus such as a barium pill, a downward bowing of the web is seen during fluroscopy.
(5) The location of the web which is in the region of oesophago-gastric junction, does not change with relationship to the stomach, but the height above the diaphragm may vary, and
(6) The lumen of the web will decrease slightly over a period of years.
Ingelfinger and Kramer postulated an active motor phenomenon stating "the constriction represents a motor phenomenon caused by intermittent contraction and burnching up of the musculature". However, Schatzki and Gary believe that the ring is rather a passive structure being present at all times, although visible only when the oesophagus proximal and distal to it is distended more than the maximum diameter of the ring. There has been a suggestion of the web being congenital in origin. Goyal et al have described two morphologically distinct types of the rings that differ in their location in the lower oesophagus. A mucosal ring, located at the squamo-columnar junction, made up of a transverse fold of mucosa that encircles the entire circumference of the oesophageal lumen, there being little contribution from the muscle wall and no evidence of inflammatory reaction. A muscular ring on the other hand is formed by a localised annular thickening, covered by squamous epithelium, and corresponds to the inferior oesophageal sphincter. Evidence of marked inflammation observed by some workers have led them to believe that the ring represents an inflammatory stricture.,, It appears that these cases represent examples of a ring like peptic structure that comes to resemble the lower oesophageal ring but is not identical.
The roentgenological picture is so characteristic that most of the usual causes of dysphagia can be excluded easily. Fibrosis following reflux oesophagitis simulates the ring more than any other lesion. In fibrosis, the narrowing is usually asymptomatic, not so short and normally not of equal length around the circumference of the oesophagus. Furthermore, endoscopy shows inflammation, ulcer or scarring.
Many patients with Schatzki's ring are asymptomatic and have no clinical importance. In symptomatic group, when dietary measures fail to control symptoms, two choices are currently available: (1) dilatation and rupture of the ring and (2) rupture of excision of the ring combined with repair of the associated hiatus hernia. Ottinger et al reviewed 36 patients with symptomatic Schatzki's ring who were treated by rupture of the ring and repair and followed up for an average of six years. Out of them, 37% had no recurrence of symptoms, 23% had recurrence of mild symptoms and 40% had recurrences of symptoms as severe as those experienced pre-operatively with recurrence of the ring and hernia in source. Thus, surgery should be offered only in patients with severe symptoms and those with reflux as predominant symptoms rather than dysphagia, with the realisation that there will be a sizable failure rate.
We wish to thank the Dean, Topiwala National Medical College and B.Y.L. Nair Hospital, Bombay for permission to publish the above case report.