Oesophageal webs are thin (1-3 mm vertical thickness) mucosal membranes typically located in the proximal (cervical) oesophagus, causing a benign luminal stenosis. They generally arise from the anterior wall, but they can also assume a circumferential shape [1, 2]. Histologically, they contain areas of hyperkeratosis and submucosal inflammation. They are more common in Caucasian middle-aged women (male-female ratio, 1:2) and are usually unique. The aetiology of oesophageal webs is controversial. Mostly idiopathic, they are associated with Plummer-Vinson syndrome, a rare disease postulated to arise from a combination of genetic factors and nutritional deficiencies, and characterised by iron deficiency anaemia, stomatitis, glossitis, cheilosis, thyroid and nail disorders. Other associations of oesophageal webs exist with graft-versus-host disease, status post-radiation therapy, benign mucous membrane pemphigoid, epidermolysis bullosa dystrophica, and gastroesophageal reflux disease for the rare distal web [1, 3].
Clinical manifestations depend on the degree of stenosis, ranging from an absence of symptoms to dysphagia and regurgitation of food, eventually leading to aspiration pneumonia.
Recommended diagnostic tests are either videofluoroscopy, or an upper GI tract barium swallowing study, where oesophageal webs typically appear during full-column distension as regular shelf- or ring-like oesophageal filling defects, possibly proximal oesophageal dilation, and a "jet effect" of contrast passing through the web's stoma [1, 4, 5]. A highly constricting proximal web can interfere with the visualisation of (rare) additional distally located webs [1], lowering the sensitivity of videofluoroscopy. Differential diagnoses for a regular oesophageal focal narrowing seen with videofluoroscopy are a normal submucosal venous plexus (slightly more irregular), a prominent crycopharyngeal muscle (only posterior, more proximal at the C5-C6 vertebra level, thicker), and rarely an A-ring or a Schatzki ring (B-ring) for narrowings in the gastroesophageal junction region.
Oesophagoscopy can be both diagnostic and therapeutic, but in oesophageal strictures appearing unequivocally benign on videofluoroscopy it is mainly indicated for treatment [6]. As a diagnostic procedure it enables confirmation of an oesophageal web and increases the detection rate of additional distal webs. As a therapeutic procedure it permits minimally invasive treatment by balloon dilation or bougienage. In less obstructing, but still symptomatic cases, dietary changes alone may prove to be sufficient [1].
Oesophageal webs may increase the risk of oesophageal cancer.
In conclusion, an oesophageal web is a rare and treatable cause of dysphagia (and aspiration pneumonia) which can be detected by high-volume swallowing studies.