Paralysis refers to a temporary or permanent loss or impairment of motor or sensory function in a part. The IXth cranial nerve is one of twelve pairs of nerves connected with the brain, which provides sensory input from the pharynx, tonsils, posterior third of the tongue and carotid arteries. It also moves the swallowing and salivary gland muscles.

Causes of paralysis of the nerve may include: tumors or lesions of the nerve or nerve root; brainstem lesions or injury; vascular lesions; chronic degenerative disorders such as amyotrophic lateral sclerosis (ALS); surgery; infections; inflammatory processes such as herpes zoster; or trauma.

Manifestations may include: diminished gag reflex; difficulty swallowing; hoarseness; deviation of the soft palate; numbness of the back wall of the pharynx; and nasal regurgitation of fluids.

Diagnostic measures may include: a complete history; physical and neurological examinations; sensory and motor tests; blood studies; spinal tap; computed tomography (CT) scan; magnetic resonance imaging (MRI).

Treatment may be directed to the specific underlying cause and symptoms. Treatment measures may include surgery and medications to treat underlying diseases or infections. Nutritional intervention and physical therapy may be needed. Other treatments for symptoms of affected neighboring nerves may also be indicated.

Regeneration of the nerve may depend on the degree of paralysis and site of injury. The closer the injury is to the central nervous system (CNS), regeneration of a severely damaged nerve is less likely to occur. There may be permanent loss of the gag reflex and sense of taste. The nutritional status may decline, and a feeding tube may be necessary. There may also be injury to neighboring nerves.

• This disease shall be granted service connection although not otherwise established as incurred in or aggravated by service if manifested to a compensable degree within the applicable time limits under 38 CFR 3.307 following service in a period of war or following peacetime service on or after January 1, 1947, provided the rebuttable presumption provisions of 38 CFR 3.307 are also satisfied [38 CFR 3.309 [Disease subject to presumptive service connection], 38 CFR 3.309(a). [chronic disease].

• Dependent upon relative loss of ordinary sensation in mucous membrane of the pharynx, fauces, and tonsils.

• Disability from lesions of peripheral portions of first, second, third, fourth, sixth, and eighth nerves will be rated under the Organs of Special Sense. The ratings for the cranial nerves are for unilateral involvement; when bilateral, combine but without the bilateral factor.