Dysphagia: causes, clinical differentiation and barium swallow findings

1. Causes of dysphagia

• Neuromuscular: stroke, Parkinson disease, motor neurone disease, myasthenia gravis, multiple sclerosis, bulbar palsy, inclusion body myositis, myotonic dystrophy.
• Muscular or cricopharyngeal: cricopharyngeal achalasia or spasm, polymyositis, dermatomyositis.
• Structural: pharyngeal pouch (Zenker diverticulum), post-cricoid web (Plummer-Vinson or Paterson-Brown-Kelly syndrome), tumours of the tongue, tonsil, pharynx or larynx, retropharyngeal abscess, post-radiotherapy or post-surgical change, cervical osteophytes.
• Mouth and pharynx lesions: tonsillitis, quinsy, painful ulcers, xerostomia.

• Foreign body, food bolus.

• Malignant: carcinoma of the oesophagus (squamous or adenocarcinoma), carcinoma of the cardia, leiomyoma and other rare tumours.
• Benign stricture: peptic (GORD), corrosive, post-radiation, post-intubation, post-sclerotherapy, drug-induced, Barrett stricture.
• Rings and webs: Schatzki lower oesophageal ring.
• Inflammatory: eosinophilic oesophagitis, candidal, herpetic or CMV oesophagitis.
• Diverticula: mid-oesophageal traction or epiphrenic.

• Enlarged left atrium (mitral stenosis), aortic aneurysm, dysphagia lusoria (aberrant right subclavian artery), mediastinal lymph nodes (malignant or tuberculous), bronchial carcinoma, goitre, paraoesophageal hernia, cervical spine disease (osteophytes, Pott disease).

• Primary: achalasia, diffuse oesophageal spasm, jackhammer oesophagus, ineffective oesophageal motility.
• Secondary: scleroderma (systemic sclerosis), Chagas disease (secondary achalasia), diabetes, hypothyroidism, amyloidosis, pseudo-achalasia from a cardia carcinoma.

• Globus, anxiety. This is a diagnosis of exclusion.

2. Clinical differentiation

• Difficulty initiating the swallow, with coughing, choking, nasal regurgitation or hoarseness, points to oropharyngeal dysphagia.
• Food sticking behind the sternum after the swallow has started points to oesophageal dysphagia.

• Mouth and pharynx: tonsils and fauces for lesions, palatal mobility, and the posterior pharyngeal wall for a retropharyngeal abscess.
• Neck: goitre, nodes, and a swelling that appears during meals above the left clavicle (late pharyngeal pouch). "Tracheal tugging" suggests an aortic arch aneurysm. Palpate the left supraclavicular fossa (Virchow node), which may be the only sign of oesophageal carcinoma.
• Chest: pleural effusion in late carcinoma. Aspiration pneumonitis, lung abscess or bronchiectasis in achalasia. Dyspnoea from a hugely dilated oesophagus. Look for a hiatal or paraoesophageal hernia.
• Abdomen: epigastric mass or hepatomegaly from cardia carcinoma and metastases.
• Spine: cervical tenderness or deformity if Pott disease is suspected.
• General: cachexia, anaemia (koilonychia and glossitis in Plummer-Vinson), skin changes of scleroderma, and cranial nerve or limb signs for neurological disease.

• Endoscopy with biopsy is the first investigation for most oesophageal dysphagia. It confirms or excludes carcinoma and stricture, and diagnoses oesophagitis and eosinophilic oesophagitis.
• Barium swallow is described below.
• High-resolution manometry is the gold standard for motility disorders.
• CT or endoscopic ultrasound is used for staging and extrinsic compression.
• Videofluoroscopy and fibreoptic endoscopic evaluation of swallowing (FEES) are used for oropharyngeal dysphagia.
• A normal endoscopy does not exclude achalasia, because 30 to 40% of endoscopies are reported normal before the final diagnosis (Bailey & Love, 28th Edition, achalasia section). Endoscopy is still needed to exclude pseudo-achalasia from a cardia cancer.

3. Barium swallow appearances

• If the history suggests obstruction but the routine images look normal, a barium-coated biscuit or a barium tablet may reveal an occult stricture.
• Use thin barium for a pharyngeal pouch. Thick barium is not washed out of the pouch (S Das, Manual on Clinical Surgery).

• Early: normal-calibre oesophagus with defective distal peristalsis, and barium retained for more than 5 minutes (Grainger & Allison).
• Established: a dilated oesophagus with a smooth, tapering narrowing at the lower end. This is described as a "bird's beak" or "rat's tail" (Bailey & Love, 28th Edition).
• Retention of contrast, an absent gastric air bubble, and abnormal contractions in the body. Progressive dilatation gives a sigmoid-shaped oesophagus.
• A chest X-ray may show an air-fluid level in a widened mediastinum.
• The narrowing is smooth and symmetrical. The mucosa is intact, and the segment relaxes after hot water or amyl nitrite.

Source: S Das, A Manual on Clinical Surgery, Fig. 31.2.

• A short, irregular, rigid stricture with an "apple core" appearance.
• Abrupt "shouldering" at the upper and lower margins, with destroyed or ulcerated mucosa.
• Proximal dilatation is modest. There may be an eccentric mass, a filling defect, or a fistula to the trachea.
• Features that favour cancer over achalasia are a short history, an irregular narrowing, shouldering, and a non-relaxing segment.
• Pseudo-achalasia (a cardia carcinoma mimicking achalasia) can look like a bird's beak. Endoscopy and CT are needed.

• A long, smooth or tapered narrowing with mild proximal dilatation, and no shouldering (S Das, Fig. 31.3).
• A peptic stricture is in the lower third and often accompanies a hiatus hernia, and may be associated with reflux. A corrosive stricture is long and may be multiple.

Source: S Das, A Manual on Clinical Surgery, Fig. 31.3.

• A "corkscrew" or "rosary bead" oesophagus from non-peristaltic, simultaneous contractions (Grainger & Allison). Transit is delayed.
• The study may be normal if the spasm does not occur during the examination.

• Reduced or absent peristalsis, a patulous gastro-oesophageal junction, and free reflux with its complications (Grainger & Allison).
• The oesophagus is dilated and atonic, and a stricture may be present.

• A small-calibre ("narrow-calibre") oesophagus. Fixed rings (the "ringed" or "feline" oesophagus) and strictures are common (Grainger & Allison).

• A posterior outpouching at the pharyngo-oesophageal junction, above the cricopharyngeus.
• The pouch fills first, then spills over. It may be large enough to displace and compress the oesophagus.

• A thin, anterior, shelf-like filling defect at the C5 to C6 level, best seen on lateral views during rapid swallowing.

• A thin, smooth, symmetrical ring at the squamocolumnar junction, just above a hiatus hernia. It is best seen with the oesophagus distended with barium.

• A smooth, extramucosal indentation that is usually pulsatile in vascular lesions.
• An enlarged left atrium causes a posterior indentation at the level of the heart.
• Dysphagia lusoria shows an oblique posterior indentation at the level of the aortic arch.

• A traction diverticulum is a small, tented outpouching in the mid-oesophagus, often from old tuberculous nodes.
• An epiphrenic diverticulum is a larger pouch above the diaphragm, often with an underlying motility disorder.

• A shaggy, "cobblestone" or plaque-like irregular mucosa, with a linear or granular filling-defect pattern, particularly in the upper and mid oesophagus.

• Videofluoroscopy shows delayed or absent initiation of swallow, nasal regurgitation, vallecular and pyriform pooling, aspiration into the larynx and trachea, and a prominent cricopharyngeal bar.
• The sequence of findings is often more informative than the static image.

4. Summary