An outline of the esophageal ring and the esophageal membrane

Article written by Doctor Mai Vien Phuong - Department of Examination & Internal Medicine - Vinmec Central Park International General Hospital

Esophageal membranes and rings are structures protruding into the esophageal lumen of the esophageal wall that can partially obstruct the esophageal lumen. The membrane and ring of the esophagus are usually asymptomatic but can sometimes present with intermittent dysphagia with solids.

The etiology of the membranes and rings of the esophagus is still a controversial topic. Several conditions are associated with the membranes and rings of the esophagus. Esophageal membranes are classically associated with Plummer-Vinson syndrome, classically a triad of dysphagia, iron deficiency anemia, and esophageal membranes.
Other associated conditions include Zenker's diverticulum disease, congenital bullous epidermolysis bullosa (generally presenting as bullous formation following minor trauma to the skin and mucous membranes, severity of the disease, The depth of the vesicle varies depending on the lesion at the molecular level, which is caused by damage to the hemidesmosome that binds the basal cell layer to the basement membrane, which can be from within the cytoplasmic membrane of the basal cell layer or extracellular and basal membrane), Pemphigus disease (Autoimmune disease, with circulating IgG autoantibodies against the surface of keratinoaftes cells, disrupting the intercellular bonds causing blistering in the epithelium. tare). On the other hand, esophageal ring is almost always involved in diaphragmatic hernia. They are also associated with eosinophilic esophagitis.

Because most esophageal membranes and rings are asymptomatic, the true prevalence of these lesions is unclear. Membrane and esophageal ring pathology is identified in 5 to 15% of patients undergoing upper endoscopy for dysphagia.
2.1 Pathophysiology of esophageal membrane and esophageal ring pathology The pathophysiology of the esophageal membrane and ring is poorly understood. Chronic inflammation can irritate the esophageal wall and create these lesions. They are also present in the pediatric population suggesting a congenital origin. If the webs and seals are large enough, they can narrow the esophagus, causing difficulty swallowing and reflux of food.
2.2 Histopathology of the esophageal membrane and esophageal ring The esophageal membrane is usually found proximal to the esophagus and is covered by a layer of squamous epithelium. On the other hand, esophageal rings are usually located distal to the esophagus and may be covered by squamous epithelium, columnar epithelium, or both depending on their location to the squamous junction:
A rings are located near the junction of the planes. They are completely covered with squamous epithelium. They are uncommon and are not usually pathological. The B rings or Schatzki rings are located exactly at the intersection of the planes. The proximal part is covered with squamous epithelium, and the distal part is covered with columnar epithelium. They are the most common type of ring and can become symptomatic. Schatzki ring:
The Schatzki ring is a narrowing of the gastro-oesophageal junction, causing dysphagia, which may be congenital, or may be due to gastroesophageal reflux. Before dysphagia occurs, the lumen of the esophagus usually narrows to less than 13 mm. The ring of Schatzki is always associated with a small sliding diaphragmatic hiatus hernia, and is always evident when the esophagus is dilated after oral administration of Barium.

Figure A: Schatzki ring on contrast-enhanced esophageal radiograph.
Figure B: bread soaked in Barium was swallowed and stuck at the Schatzki ring.
Source: A.H.A. Chapman, (2000)

The C rings are located far from the plane intersection point. They are completely covered with columnar epithelium. They are the least common, rarely symptomatic, and usually represent indentation of the diaphragm of the esophagus.