Dysphagia is derived from 2 Greek terms ‘dys’  meaning ‘difficulty’ in swallowing ‘phagia’ meaning ‘to eat’ in Greek. It indicates difficulty in swallowing food after chewing in the mouth. It is a common problem for which patients seek medical attention.

Swallowing is the process by which food safely passes from the mouth to the pharynx (the common area where food-pipe and wind-pipe open) to the esophagus to the stomach (food pipe) without any food particle entering in the wind-pipe. Once the food bolus reaches inside the esophagus, the muscles of the esophagus rhythmically contract to push the food bolus down into the stomach. This process is called peristalsis (‘peri’ means to wrap around ‘stallein’ means to place). So, you can imagine the bolus entering the pipe, and the portion of the pipe behind the bolus contracts pushes it ahead. The contraction must be sufficient to push the bolus ahead plus the portion of the pipe ahead of the bolus has to remain uncontracted so to allow for smooth passage of food. A series of such contractions occur, and food eventually reaches the stomach. Any abnormality in any of these processes can cause dysphagia.

Therefore, to understand and simplify the causes of dysphagia, the tract can be divided into oropharyngeal ( mouth+pharynx, also upper portion) and esophageal (lower portion).

Oropharyngeal dysphagia mostly causes problems with initiation/beginning of swallowing. Since the passage of food may be affected in the pharynx as well, it may cause food particles to enter the windpipe. As the windpipe does not allow anything but air, it tries to throw out the particles. This causes choking (blockage of air, initially) and coughing (attempt to throw out) to dislodge particles from its tract. So, the common symptoms which may indicate this form of dysphagia are:-

1. 1)Difficulty in the initiation of swallowing
2. 2)Choking sensation
3. 3)Coughing

Esophageal dysphagia occurs due to an inability of the food to pass to the stomach after it enters the esophagus. Essentially, the food bolus gets ‘stuck in the food pipe. This is primarily due to 2 reasons. Either there is something blocking the food producing a  mechanical obstruction, or any dysrhythmia (‘dys’ meaning difficulty or abnormality ‘rythmia’ meaning of the rhythm)  of the muscles of the esophagus.

Mechanical obstructions are mainly due to strictures, rings, webs, or masses. Stricture, rings, and webs are benign conditions causing narrowing of the lumen. Masses are mostly due to malignant conditions like esophageal cancer. Usually, mechanical conditions obstruct the lumen incompletely and therefore produce difficulty in the passage of solids mostly. Also, the time course of dysphagia is gradual and chronic usually taking months to years i.e starts slowly progresses slowly and may cause difficulty swallowing liquids as the lumen gets narrower.

On the other hand, rhythmic disturbance ( also called motility disorder, motile in Latin means ‘motion’ i.e ‘to move’) has different causes and courses of progression. The commonly observed motility disorders include Achalasia cardia, diffuse esophageal spasm, and hypertensive peristalsis.  Motility disorders produce total or complete occlusion causing dysphagia to both solids and liquids. Also, they present suddenly or abruptly and cause significant discomfort.

To summarize the symptoms of esophageal dysphagia:-

1. 1)Feeling of ‘food’ getting stuck
2. 2)Difficulty in swallowing solids and liquids depending on etiology.
3. 3)Disease course may be abrupt or gradual depending on etiology.

The approach to dysphagia is through proper clinical history, screening for risk factors for cancer or any other chronic diseases. Based on history and full physical examination, identification of etiology is supplemented with procedures like barium swallow, videofluoroscopy swallowing ( mainly for oropharyngeal dysphagia), or upper endoscopy (for esophageal disorders). In case motility disorder is suspected, esophageal is the gold standard technique to identify the cause.