What Are the Different Types of Vagus Nerve Damage?

The vagus nerve is the longest and most widely distributed cranial nerve. It exits the skull together with the glossopharyngeal nerve and the accessory nerve through the jugular foramen. It is located in the carotid sheath in the neck and descends between the carotid artery and the internal jugular vein. . The vagus nerve is a mixed nerve. The nucleus of the vagus nerve, the nucleus of the solitary bundle, and the nucleus of the trigeminal spine coexist with the glossopharyngeal nerve. Therefore, simple vagus nerve injury is rare and often occurs simultaneously with the glossopharyngeal nerve.

Basic Information

English name: Vagus Nerve Injuries
Visiting department: neurosurgery
Common causes: Skull base fracture, neck firearm injury, iatrogenic injury, skull base tumor, etc.

Common symptoms: Damage to one side of the pharyngeal, vagus nerve or its nucleus can cause coughing and hoarseness; bilateral damage to eating, swallowing, severe pronunciation disorders, and salivation in severe cases

Causes of vagus nerve injury

Skull base fracture

Symptoms of glossopharyngeal nerve, hypoglossal nerve, and accessory nerve can occur at the same time.

2. Neck firearm injury

Can damage the vagus nerve stem or its branches. The upper part of the vagus nerve is often injured when the mastoid, mandibular, and posterior mandibular spaces are damaged; only the recurrent laryngeal nerve is injured in the lateral injury of the mandible; the vagus nerve is located behind the large neck blood vessels and moves with the vascular bundle. Vagus nerve stem damage can occur.

3. Iatrogenic injury

Jugular foramen tumor surgery can damage the vagus nerve, thyroid surgery can damage the superior laryngeal nerve, recurrent laryngeal nerve and so on.

4. Skull base tumor

Tumors in the foramen of the jugular vein, such as bulbous tumors of the jugular vein, schwannoma; tumors in the medullary region can damage the vagus nerve.

5. Other

Such as bulbar vascular disease, encephalitis caused by bacteria or virus can damage the glossopharyngeal nerve, vagus nerve or its nucleus.

Clinical manifestations of vagus nerve injury

When the glossopharyngeal, vagus nerve or its nucleus is damaged on one side, the ipsilateral soft palate paralysis and pharyngeal reflex may disappear, and cough and hoarseness may occur. When bilateral damage occurs, the patient has severe disturbances in eating, swallowing, and pronunciation. In severe cases, the patient cannot even pronounce, swallow, and salivary fluid, which is called true bulbar palsy.

Vagus nerve injury examination

1. Routine and biochemical detection of cerebral effusion

There may be an increase in white blood cell count during encephalitis. CSF biochemical detection in jugular foramen tumors has no significant clinical significance.

2. X-ray of skull base

Fractures of the skull base caused by trauma can be diagnosed.

3. Skull CT and magnetic resonance examination

Spiral CT skull base bone imaging is more meaningful for the diagnosis of skull base fractures. It can also help diagnose skull base tumors, brain stem tumors, vascular lesions, and encephalitis.

4. Brainstem evoked potential examination

It is also valuable for the diagnosis of brain stem or brain stem lesions involving posterior cranial fossa lesions.

Diagnosis of vagus nerve injury

Diagnosis of vagus nerve can be confirmed based on medical history and neurological examination and auxiliary examination.

Vagus nerve injury treatment

Cause treatment

(1) Firearm injuries Firearm nerve injuries are mostly caused by high-speed projectiles (shrapnel or gun bullets), which have a wide range of nerve damage, severe contamination of the wound, and prone to wound infection. The initial treatment principle is: the wound should be thoroughly debrided instead of sutured nerves; the injured part of the nerve should not be removed, and free stumps should not be made to prevent the spread of pollution; nerve stumps should not be marked with silk threads, and should not be sutured in tissue Covering free nerves with normal tissue; promoting wound healing as soon as possible, creating conditions for secondary repair.

(2) Fracture of the skull base The fracture of the skull base itself does not require special treatment. The focus of treatment is to prevent infection and the rational use of antibiotics. Cerebrospinal fluid nasal leak or ear leak are contraindicated for stuffing, blowing the nose, reducing sneezing, coughing, and keeping the external ear canal clean. Try to avoid lumbar puncture to prevent retrograde infection.

(3) Strengthening neuroprotection during the operation It is important to carefully protect the vagus nerve and glossopharyngeal nerve from irreversible damage when applying microneurosurgical techniques when performing skull base surgery. The treatment of small tumors in the foramen of the jugular vein for stereotactic radiosurgery should be reasonably and scientifically designed to avoid aggravating vagus nerve and glossopharyngeal nerve injury. When performing thyroid surgery and carotid endarterectomy, you should be familiar with the anatomy of the recurrent laryngeal nerve and the superior laryngeal nerve and their relationship with surrounding blood vessels. Apply good microsurgical techniques and use EMG monitoring techniques during surgery. The upper laryngeal and recurrent laryngeal nerves are effectively protected. If the recurrent laryngeal nerve is severed during the operation, the recurrent laryngeal nerve-vagus nerve cervical end-to-side anastomosis is feasible, and it is expected to receive good results in the long run.

(4) Central nervous system inflammation requires anti-inflammatory treatment, anti-inflammatory treatment should be early, and the course of treatment should be sufficient. Need to choose antibiotics that easily penetrate the blood-brain barrier.

(5) Microsurgery, X-knife, Gamma-knife treatment should be performed on the medullary vascular lesions as appropriate.

(6) Skull base tumors undergo surgical treatment or stereotactic radiotherapy as appropriate. Tumors in the foramen magnum area are mainly resected in the extracranial segment, and those with intracranial remnants should undergo stereotactic radiation therapy. Glioma of the medulla oblongata is confined to patients who can only be treated with microsurgical resection, combined with stereotactic radiation therapy and chemotherapy.

Symptomatic treatment

(1) Patients with severe choking should take a pasty semi-liquid food to avoid puffing into the airway and cause pneumonia.

(2) Patients with high intracranial pressure will be given treatment to reduce intracranial pressure. Commonly used are 20% mannitol, fructose, and glucocorticoid.

(3) feasible antiemetic treatment for headache, nausea and vomiting .