Changes in swallowing
The difficulty in swallowing (dysphagia) is a symptom that, associated with other clinical data, does not usually pose diagnostic problems.
On the other hand, when presented in isolation, it should be carefully evaluated by means of the corresponding instrumental studies so as not to overlook potentially serious conditions.
Usually the patient refers to difficulty starting to swallow, or a sensation of constriction in the throat or behind the sternum.
It is necessary to distinguish this symptom from the sensation of a mass in the throat, generally not related to swallowing. Dysphagia should not be confused with painful swallowing (odynophagia), although both symptoms may be associated with an ongoing inflammatory process.
Within dysphagia two types are distinguished: the oropharyngeal and the esophageal, which differ from one another by the phase of swallowing affected in each case.
Oropharyngeal dysphagia is spoken when there is difficulty for the bolus to pass from the oropharynx to the upper part of the esophagus. Physiological swallowing is the result of a rapid series of perfectly coordinated phases, lasting approximately 1.5 seconds. The process consists of a voluntary phase during which the tongue pushes the bolus towards the pharynx; once it has left the oral cavity, swallowing becomes involuntary, controlled by nervous reflexes.
The pharyngeal muscles contract in peristaltic sequence and the upper esophageal sphincter relaxes to allow passage of the alimentary bolus to the esophagus.
Aspiration is avoided by elevating the larynx, closing the laryngeal lobes, lowering the epiglottis and discontinuing respiration.
Patients with oropharyngeal dysphagia report difficulties at the beginning of swallowing; Other possible symptoms are: choking sensation, nasal regurgitation, cough and aspiration asphyxia. Oropharyngeal dysphagia tends to worsen with swallowing of beverages, contrary to what happens in esophageal dysphagia, in which it is more difficult to ingest solid foods.