In this section we will discuss the two main cranial nerves - the trigeminal nerve (Vth cranial nerve) and facial nerve (VII cranial nerve). Why are they basic? Because these nerves perform two main functions for the face: sensory and motor. So now let's find out who is responsible for what.
This is a very large nerve that has three branches on the face: ocular, maxillary and mandibular, each responsible for its own area. Its main function is sensitive, namely the sensitivity of the soft tissues of the face, mucous membranes of the mouth and nose, as well as the dura mater. The trigeminal nerve also contains part of the motor fibers that are responsible for the masticatory muscles.
What can happen to this nerve?
In general, all the causes of trigeminal neuralgia (trigeminal neuralgia) are divided into 3 groups:
- Classical: there is a conflict between the root of the trigeminal nerve and the vessel (the vessel begins to press on the root), called neurovascular conflict
- Secondary: the nerve may be affected by other diseases of the nervous system (tumors, multiple sclerosis, basal meningitis)
- Idiopathic: no other diseases of the nervous system, no neurovascular conflict or it has not led to morphological (structural) changes
How does the trigeminal lesion manifest itself?
A typical attack of trigeminal neuralgia should not be confused with anything, it has clear characteristics:
- Pain in the face (may have a specific location depending on which branch is affected) is paroxysmal (episodic) and shooting nature
- This pain usually lasts from a few seconds to several minutes
- The intensity of pain is significant
- Presence of trigger zones - hypersensitive areas, irritation of which can provoke an attack of pain (during shaving, chewing, yawning and even when talking)
- Occasionally there may be autonomic symptoms (tearing, redness of the eye on the affected side)
- At the height of the pain in some patients there was a painful tic (tingling of the facial muscles) ¹
So what to do if you have the above symptoms?
You need to consult a doctor as soon as possible. During the consultation, the doctor will determine further tactics and additional methods of examination. to find out the group of causes that have led to your nerve damage. And then, depending on the results of the examination, carry out appropriate treatment: whether it will be symptomatic drug therapy, whether it will be surgery, or it will be therapy aimed at combating other diseases of the nervous system that lead to secondary trigeminal neuralgia.
To treat trigeminal neuralgia, your doctor usually will prescribe medications to lessen or block the pain signals sent to your brain. The most commonly used groups of anticonvulsants, muscle relaxants or even botulinum toxin injections. Small studies have shown the effectiveness of Onabotulotoxin in the treatment of trigeminal neuralgia. Surgical treatment may include microvascular decompression (through a small incision the trigeminal nerve is released from the pressure of a nearby vessel), radiosurgery (gamma radiation destroys the trigeminal root and as a result the patient loses pain).
The facial nerve cannot hurt because it does not contain sensitive fibers. It performs motor and autonomic (parasympathetic) function. This nerve provides work to all facial muscles (motor fibers), and it is responsible for the secretion of tears, the taste of 2/3 of the front tongue and even for the transmission of auditory vibrations (all due to parasympathetic fibers). Why is it important to know about these features? －Depending on the presence of symptoms of lesions of these parasympathetic branches, a neurologist can understand the specific place where the lesion of the facial nerve, respectively, can determine the cause of the lesion with additional methods of examination.
What can affect the facial nerve?
The main cause of the lesion is considered to be compression of the nerve in the place where it passes (facial nerve canal), the size of this canal in all people is different (and this is usually genetically determined). Therefore, in the case of provoking factors (neuroviral infections, ischemia) in these people there is inflammation of the facial nerve. Possible triggers (causes) include:
- Ear damage
- Tumors of the pons-cerebellar angle
- Basal meningitis, encephalitis
- Viral infections (the most common pathogens of the herpes virus group, as well as influenza virus, mumps, enteroviruses)
- Somatic diseases (diabetes, high blood pressure, toxins)
- Cosmetic interventions
- Other diseases of the nervous system (multiple sclerosis) ³
How to understand that this is a lesion of the facial nerve?
When the doctor at the examination asks you to frown, smile or show your teeth, he is not doing it for fun, but to check the function of the facial nerve. Symptoms of facial nerve neuropathy include:
- Lack of movement of half of the face (and as a result of asymmetry of the face, one half slightly lowered, lowered corner of the mouth, smoothed nasolabial fold)
- Dilated eye slit or inability to close the eye completely on the affected side
- Tearing or dryness of the eye on the affected side (depending on the level of damage, which is of great diagnostic value)
- Hypersensitivity to sounds, tinnitus or hearing loss
- Dry mouth
- Taste disturbance on the front 2/3 of the tongue
Diagnosis and treatment of facial nerve neuropathy
In case of at least one of the above symptoms, consult a doctor immediately. The result of the restoration of nerve function (and hence the restoration of facial muscle movements and facial symmetry) directly depends on how early to start treatment. During the examination, the doctor, depending on your complaints and the results of the neurological examination, will decide on the need for additional research, and if so, which ones. Then there will be an immediate opportunity to move on to treatment. Treatment tactics are divided into 3 groups: drug therapy, surgery and physical therapy. The drug group includes hormone therapy, antiviral therapy (most often antiherpesvirus drugs), and symptomatic use of moisturizing eye drops or artificial tears. The key point in treatment is physical therapy. And this type of therapy depends only on the patient. Physical therapy includes: self-massage of the affected half of the face by special techniques, as well as daily exercise for facial muscles. Examples of exercises and massage your doctor will give you during the consultation, as well as tell you how to do them correctly. There is also sometimes a need for physiotherapy (electrical stimulation of the facial nerve), acupuncture.
Take care of yourself and your nerves, and especially your face nerves!
1. Neurology: textbook /I.A. Grigorova, L.І. Sokolova, R.D. Gerasimchuk and others; for ed. I.A. Grigorova, L.I. Sokolova. - K .: VSV "Medicine", 2014. - p.259
2. Name from the screen. - https://www.mayoclinic.org/diseases-conditions/trigeminal-neuralgia/diagnosis-treatment/drc-20353347
3. Name from the screen. - https://www.hopkinsmedicine.org/health/conditions-and-diseases/bells-palsy
4. Name from the screen. - https://www.ninds.nih.gov/health-information/patient-caregiver-education/fact-sheets/bells-palsy-fact-sheet#3050_6