Investigation of cranial nerves. IX AND X Pairs: Glossopharyngeal and vagus nerves

The motor branch of the glossopharyngeal nerve innervates the shigellar muscle (t. Stylopharyngeus).

Vegetative parasympathetic secretory branches go to the ear ganglion, which in turn sends the fibers to the parotid salivary gland. The sensory fibers of the glossopharyngeal nerve supply the posterior third of the tongue, the soft palate, the pharynx, the skin of the outer ear, the mucosa of the middle ear (including the inner surface of the tympanic membrane), and the Eustachian tube; visceral sensory afferents carry impulses from the carotid sinus; The taste fibers carry a sense of taste from the posterior third of the tongue. The wandering nerve innervates the striated muscles of the pharynx (except the shillopharyngeal muscle), the soft palate (except for the trigeminal nerve muscle that stretches the palatine curtain), the tongue (m. Palatoglossus), the larynx, the vocal cords and the epiglottis. Vegetative branches go to the smooth muscles and glands of the pharynx, larynx, internal organs of the thoracic and abdominal cavity. Visceral sensory afferents conduct impulses from the larynx, trachea, esophagus, internal organs of the thoracic and abdominal cavity, from the aortic arch baroreceptors and the aortic chemoreceptors. Sensitive fibers of the vagus nerve innervate the skin of the outer surface of the auricle and the external auditory canal, part of the outer surface of the eardrum, pharynx, larynx, and a solid medulla of the posterior cranial fossa.

The glossopharyngeal and vagus nerves have several common nuclei in the medulla oblongata and run close together, their functions are difficult to separate, so they are examined simultaneously.

When collecting an anamnesis, it is determined whether the patient has problems with swallowing, speech (voice).

Vote

Pay attention to the clarity of speech, timbre and sonority of the voice. If the function of the vocal cords is disturbed, the voice becomes hoarse and weak (up to aphonia). Due to a malfunction of the soft palate, not enough to cover the entrance to the nasopharynx cavity during phonation, a nasal shade of the voice (nasolalia) appears. Violation of the function of the larynx muscles (defeat of the vagus nerve) affects the pronunciation of high sounds (u-and-u), which requires the convergence of the vocal cords. In order to exclude the weakness of facial muscles (VII pair) and the muscles of the tongue (XII pair) as a possible cause of speech disturbance, the patient is offered to pronounce lip (p-p-p, mi-mi-mi) and front-lingual (la-la-la) sounds or syllables, including them. The sonicity of the voice is revealed when the syllables are spoken, having in their composition guttural sounds (ha-ha-ha, kai-kai-kai). The patient is also offered to forcibly cough. A patient with acute unilateral paralysis of the vocal cords is not able to pronounce the sound "i-and-and" or forcedly cough.

Palatine curtain

A soft palate is examined when the subject pronounces the sounds "aaaaaaaaa" and "ei". Evaluate how fully, strongly and symmetrically the soft palate rises during phonation; Do not deviate in the direction of the tongue of the palatine curtain. With unilateral paresis of the muscles of the soft palate, the palatine curtain falls behind on the side of the lesion during phonation and is pulled by healthy muscles in the opposite side of the paresis; The tongue deviates to a healthy side.

Palatine and pharyngeal reflexes

A wooden spatula or a strip (tube) of paper gently touch the mucous membrane of the soft palate alternately from two sides. The normal answer is pulling the palatine curtain up. Then touch the back wall of the pharynx, also on the right and left. Touch causes swallowing, sometimes vomiting. Reflex response is expressed in varying degrees (in older persons may be absent), but in norm it is always symmetrical. The absence or decrease of reflexes on one side indicates a peripheral lesion of IX and X pairs of cranial nerves.