Dysphagia is a medical term given to the condition characterized by difficulty in swallowing. This shouldn’t be confused with another term ‘Odynophagia’ which sounds quite similar to ‘dysphagia’.
Dysphagia is difficulty or disability in swallowing, whereas Odynophagia is the term given to painful swallowing.
By definition, dysphagia can be described as the subjective sensation evoked, when the food which is supposed to pass through the mouth, esophagus, and then enters the stomach, is impeded in one or the other way.
Most of the times dysphagia is accompanied by odynophagia.
This condition may also be accompanied by a pain sensation in the chest, in most cases.
To properly understand the cause of dysphagia and its treatment options, we need to learn how exactly the normal swallowing process takes place.
Physiology of Normal Swallowing
Normal swallowing, otherwise known as deglutition is a process controlled by the Vagus nerve in our body and its center is located in the region of the medulla oblongata.
The normal swallowing process takes place in three stages.
Stage 1: Oral Stage
This is a voluntary stage. It is in this stage the chewing of food takes place and the food is formed into the oral bolus.
Bolus is nothing but the ball-like mixture comprising of food and saliva that forms in the mouth during the process of chewing. This bolus is then pushed towards the pharynx, by the action of the tongue.
Stage 2: Pharyngeal Stage
This is an involuntary (not in our control) stage. In this stage, the food passes through the pharynx across the upper esophageal sphincter and enters the proximal part of the esophagus.
This whole process takes place within a second and is divided into five main parts.
Part 1: The elevation of soft palate takes place which is then retracted to prevent regurgitation.
Part 2: The vocal cords are closed and the epiglottis closes the larynx to prevent aspiration.
Part 3: The Upper Esophageal Sphincter relaxes.
Part 4: The larynx is pulled upwards which then opens the esophagus and upper sphincter.
Part 5: The pharyngeal muscles contract which then pushes the food into the esophagus.
Stage 3: Esophageal Stage
In this stage, the food enters the stomach from the esophageal sphincter.
Dysphagia Causes, Classifications, and Symptoms
Classification of Dysphagia
A broader classification of dysphagia can be done as follows.
When there is an obstructive lesion, that causes dysphagia.
Motility Related Dysphagia
This is a condition caused by abnormal motility of digestive tract/organs.
When the motility is normal and the reason may be of psychological origin.
Symptoms and Clinical Features of Dysphagia
- Painful swallowing or odynophagia is a common symptom.
- Pain in the chest area while swallowing may also be frequently felt.
- Regurgitation and heartburn are felt in many patients.
- Nausea and vomiting may be seen in severe cases.
- Weight loss may be seen in severe cases of dysphagia, which need immediate intervention.
- Pneumonia may occur in cases with associated tracheoesophageal fistula.
- Hoarseness is seen in some people.
- Gastrointestinal bleeding is seen in severe cases, which again is an emergency.
Based on the causes this condition can be classified into Oropharyngeal dysphagia and Esophageal dysphagia.
This usually results from abnormal functioning of one of the following.
- Nerves and muscles of the mouth
- Upper Esophageal Sphincter
The other reasons that may cause Oropharyngeal dysphagia are
- Neuromuscular disorders
- Central Nervous System disturbances
- Parkinson’s disease
- Tumor and Cerebrovascular Trauma
- Multiple Sclerosis
- Peripheral Neuropathy
- Myasthenia Gravis
- Skeletal Muscles Diseases
- Muscular Dystrophies
- Cricopharyngeal UES Dysfunction
- Obstructive lesions in the region such as tumors, esophageal web, Zenker’s diverticulum or conditions caused by certain medications.
- Extrinsic structural lesions such as Cervical spondylosis and Cervical masses.
Causes of Esophageal Dysphagia
Below are the main causes of esophageal dysphagia.
- Esophageal Web
- Enlarged Aorta
- Diffuse Esophageal Spasm
- Other Motility Disorders
- Hypertensive Lower Esophageal Sphincter
- Giant Left Atrium
- Substernal Thyroid
- Mediastinal Masses
- Enlarged Lymph nodes
- Lower Esophageal Ring
- Foreign Body stuck inside the region
- Esophageal Carcinoma
How Do They Diagnose Dysphagia?
If someone has difficulty in swallowing and has associated symptoms, he/she may be advised to undergo following diagnostic procedures to determine the cause and type of dysphagia.
One or more of the following tests may be advised.
- Barium swallow or Barium meal test
- Indirect Laryngoscopy
- MRI or Magnetic Resonance Imaging
- Esophageal Manometry
- Esophageal Scintigraphy
- Video Fluoroscopic Evaluation
- Endoscopic Examination and Esophageal Biopsy if necessary.
Treatment for Dysphagia
The treatment for dysphagia is mostly based on the cause of the disease.
However, the treatment commonly involves making adjustments to the type of food eaten on a daily basis and its consistency.
The exact food texture that needs to be swallowed by the patient will be decided by the doctors and dieticians only after conducting suitable tests/investigations. The food containing balanced vitamins and minerals along with some kind of laxative may be advised to facilitate swallowing.
If there is any discrepancy in the head and the neck position during swallowing, that needs to be rectified too.
If there are any obvious oral reasons that are causing dysphagia, the dental surgeon usually takes care of these conditions first, before referring the individual to other specialties.
Difficulty in swallowing caused due to the narrowing of the esophagus or strictures, the esophageal distension/dilatation may be carried out using balloons that are passed through an endoscope or using dilators.
People suffering from eosinophilic esophagitis may be treated using acid lowering agents or steroids.
Difficulty in swallowing caused by Achalasia may be managed with nonsurgical treatment like Pneumatic dilation or Botox or with surgical procedures such as Heller myotomy, Fundoplication or Peroral endoscopic myotomy (POEM).
In cases of tumors, surgical removal may be required in most cases. In the case of Carcinomas, an interdisciplinary approach among the doctors may be followed, for the proper management of the condition.
The need for surgery and the type of surgery is usually decided by the Gastro Enterologist and/or a general surgeon.
Even using substances like artificial saliva and other artificial lubricants may help the individual to swallow the food comfortably.
Difficulty in swallowing isn’t a common disease. If you or someone you know is suffering from such a condition please visit your dentist or the doctor immediately for consultation and treatment.
Diagnosing the disease and its cause at an early stage is very important to manage the condition effectively and efficiently.