Pharyngeal sensitivity disorders: causes, symptoms, diagnosis, treatment

Disorders of the sensitivity of the pharynx are divided into anesthesia, hypoesthesia, hyperesthesia and paresthesia.

Anesthesia and hypoesthesia are characterized by the disappearance or sharp decrease in the expression of the pharyngeal reflex. Sensitivity disorders are observed most often after diphtheria, in subatrophic and atrophic processes (ozena of the pharynx), in leprosy processes, in epileptics treated with bromine preparations, less often in tabes dorsalis, syringomyelia affecting the bulbar centers of the sensory nerves of the pharynx; very often observed in people suffering from hysteria. Unilateral anesthesia can be observed in syringobulbia, sometimes in hysteria, after damage to the sensory nerves of the pharynx by herpes zoster. Damage to the glossopharyngeal nerve leads to anesthesia of the pharynx, and part of the sensory fibers of the vagus nerve - the soft palate and palatine arches.

Hyperesthesia in some cases occurs with tabes dorsalis, in some hysterics with neuralgia of the glossopharyngeal nerve. This disease was described by the French neurologist R. Sicard and was called Sicard's syndrome, which is characterized by the sudden occurrence of unbearable (dagger) pain in the corresponding half of the soft palate, resembling an electric shock, radiating to the corresponding half of the pharynx, the root of the tongue, the ear-temporal region and the eye. The pain is paroxysmal and lasts from several seconds to 3 minutes and can be repeated several times a day.

An attack is usually provoked by swallowing, chewing, tugging the tongue, speaking in a loud voice, pressing on the area of the angle of the lower jaw, washing the face with cold or hot water, or cold or hot food. Sicard's syndrome is characterized by the fact that in the area of the mucous membrane of the root of the tongue or the back wall of the pharynx there are limited areas (the so-called trigger zones), touching which provokes the onset of an attack, which resembles the trigger mechanism of pain in Sluder's syndrome (frequent sneezing, constant, less often paroxysmal, burning, drilling, pulling pain in the inner corner of the eye, in the eyeball, nose, upper jaw, palate; pain often radiates to the back of the head and shoulder; kinesthesia of the mucous membrane of the upper alveolar process, palate and pharynx on the affected side, unilateral lacrimation; can be provoked by the same factors as an attack of pain in Sicard's syndrome).

An attack can also be provoked by pressure on the palatine tonsils, for example, when it is necessary to extract caseous masses from the lacunae during CT.

Due to severe pain, patients experience a fear of eating, which leads to gradual weight loss; such patients try to speak in a quiet voice, their speech is unclear, they avoid active sneezing and yawning.

Before an attack, there is often a feeling of numbness of the palate and short-term hypersalivation. In addition, there is unilateral hypergeusia with increased sensitivity to bitterness in the area of the posterior third of the tongue (the innervation zone of the glossopharyngeal nerve). During an attack, a dry cough often occurs.

Neuralgia of the glossopharyngeal nerve is not accompanied by disturbances in the motor function of the pharynx, taste sensitivity, or any objective signs of disturbance of general sensitivity.

The cause of glossopharyngeal neuralgia is unclear in most cases. In each case, the patient needs to undergo an X-ray examination to exclude a giant styloid process and diseases of the dental root system. Signs of glossopharyngeal neuralgia may occur with malignant tumors of the palatine tonsils or pharynx, as well as in the area of the MMU with damage to the root of the IX cranial nerve, arachnoiditis in this area, aneurysm of the internal carotid artery, syphilis, etc.

Differential diagnostics are performed between essential neuralgia of the glossopharyngeal nerve and symptomatic (secondary) neuralgia caused by an inflammatory, toxic, vascular, tumor or other cause. Pain in secondary neuralgia of the glossopharyngeal nerve is constant, in contrast to the paroxysmal periodic pain in essential neuralgia (Sicard's syndrome). The specified syndrome is also differentiated from neuralgia of the third branch of the trigeminal nerve, which is also paroxysmal in nature, from neuralgia of the superior laryngeal nerve, in which pain occurs with pressure on the area of innervation by this nerve, produced between the greater horn of the thyroid cartilage and the horn of the hyoid bone, from the posterior sympathetic Barre-Lieou syndrome (occurs with cervical osteochondrosis and deforming spondylosis; manifests itself as headache, usually in the back of the head, dizziness, imbalance, noise and pain in the ears, visual and accommodation disorders, neuralgic pain in the eyes and face, etc.; the disease is associated with irritation of the sympathetic plexus of the vertebral arteries and secondary hemodynamic disorders in the basilar artery pool), in which signs occur that resemble symptoms of neuralgia of the IX nerve: glossodynia, swallowing disorders, atrophy of the pharyngeal muscles and laryngeal dysfunctions.

Treatment of neuralgia of the glossopharyngeal nerve is divided into symptomatic and radical (surgical). The first consists of blockades by introducing a solution of novocaine into the retrotonsillar space and into the area of the superior plus of the palatine tonsil. This procedure stops the occurrence of attacks for some time. Surgical treatment consists of cutting the IX nerve either by extracranial or intracranial access.