Facial paralysis: Description
Facial paralysis originates from a disorder of the facial nerve and is therefore also called facial nerve palsy or facial nerve palsy.
Facial nerve, the seventh cranial nerve
In addition, the facial nerve also plays a role in the sensation of touch, taste, the production of saliva and lacrimal fluid, and hearing. One of its branches, the chorda tympani, is responsible for taste perception in the anterior region of the tongue, for example, while the stapedius nerve is important for hearing.
Central and peripheral paralysis
In peripheral paralysis, the nerve itself is disturbed at some point along its course. In contrast to central paralysis, those affected can usually no longer move the entire half of their face, including their forehead and eyes. They can no longer frown, for example.
Facial paralysis: causes and possible diseases
Both peripheral and central facial nerve palsy can have different causes.
Peripheral paralysis
In the most common form of hemifacial paralysis, the cause is unknown. This phenomenon is also known as “Bell’s palsy”. In the remaining cases, diseases are behind the peripheral paralysis.
Peripheral facial paralysis with unknown cause
Medical experts suspect that Bell’s palsy is an autoimmune inflammatory reaction of the facial nerve. This can be caused by factors such as drafts, stress, pregnancy, cycle fluctuations, and bacterial or viral infections. The inflammation causes the facial nerve to swell – it becomes literally trapped in the narrow bony canal and thus damages itself.
Peripheral facial palsy with known cause.
Various diseases as well as injuries to the facial nerve can cause facial paralysis. The most common are:
Hereditary diseases:
- Möbius syndrome: Bilateral facial paralysis gives even infants a mask-like rigid facial expression. Several cranial nerves may be underdeveloped and damaged here.
Bacterial infections
- Middle ear infection (otitis media): Otitis media, which is caused by bacteria, is not only very painful, but can also bring a dreaded complication: Due to the anatomical proximity of the facial nerve to the ear, the inflammation can spread into the bone canal and nerve, leading to temporary facial paralysis.
- Other bacterial causes of facial paralysis: scarlet fever, inflammation of the parotid gland, meningitis.
Viral infections
- Other viral causes of facial paralysis: chickenpox (varicella), mumps, influenza (flu), polio (poliomyelitis or polio for short).
Autoimmune diseases
- Sarcoidosis / Boeck’s disease: Here, small tissue nodules form in the lungs. The disease can also affect the face (Heerfordt syndrome): Fever, inflammation of the parotid gland and lacrimal gland, and facial paralysis are typical signs.
Tumors
Tumors of the nerve or adjacent areas can also cause facial paralysis:
- Acoustic neuroma: The most common tumor of the brainstem is initially manifested by tinnitus and hearing impairment.
- Tumors of the facial nerve
- Tumors of the parotid gland: malignant tumors often cause facial paralysis
- Neurofibromatosis Recklinghausen: inherited multi-organ disease affecting mainly the skin and nervous system
- Metastases of other tumors
Injuries
- Birth trauma: forceps delivery
- Craniocerebral trauma with fracture of the petrous bone
- Facial injuries in the area of the parotid gland
- Barotrauma in the middle ear due to flying or diving
Central facial nerve palsy
Causes of central facial paresis include any disease of the brain that causes disturbances in the core area of the facial nerve. These include:
- Cerebral infarction (stroke caused by hemorrhage or vascular occlusion).
- Tumors
- Injuries
- Polio (poliomyelitis)
- Multiple sclerosis
The occurrence of facial paralysis alone is rare in central facial paralysis. Frequently, an arm or a complete half of the body is also affected. Disorders during urination (e.g. incontinence) are also typical accompanying symptoms.
Facial paralysis: When do you need to see a doctor?
Signs of a stroke include:
- sudden weakness or paralysis, usually of one half of the body (face, arms and legs)
- sudden visual disturbances: double vision, impaired vision, restricted field of vision
- Sudden speech disorders: slurred, difficult-to-understand speech, word-finding disorders, comprehension disorders, meaningless word salad
- drowsiness, dizziness, headaches
- sudden change of consciousness: e.g. aggression or disorientation
However, you should also consult a doctor for clarification if you experience temporary numbness or signs of paralysis in the face. If the symptoms are mild, you can also consult your family doctor first. He or she can arrange for further examinations or refer you to a specialist (neurologist).
Facial paralysis: What does the doctor do?
Diagnosis of facial paralysis
However, the first step is the patient interview to obtain the patient’s medical history (anamnesis). Important questions for the physician include the following:
- When did the first signs of paralysis appear?
- How exactly do they manifest themselves?
- Do you have any other complaints (e.g. headaches)?
- Do you suffer from high blood pressure?
Blood tests and a smear test help to detect the pathogen. The detection of Borrelia, herpes viruses or other pathogens can provide initial indications of the cause of the facial paralysis.
Thus, paralysis of individual or all facial muscles indicates a nerve lesion outside the skull. If the nerve is damaged in a more internal section, hemifacial paralysis may be joined by other symptoms, such as:
- taste disturbances in the front two thirds of the tongue
- Decreased salivation
- Sensory disturbances in the area of the ears
- increased sensitivity to sound (hyperacusis)
- reduced lacrimation and dry nasal mucous membranes
Important neurological examination methods are electromyography (EMG) and electroneurography (ENG): This tests the electrical muscle activity (EMG) and the functional state of nerves (ENG), respectively. This helps to substantiate the diagnosis of facial paralysis.
It is also important to distinguish between central and peripheral facial paralysis. If the patient can no longer frown, this indicates peripheral facial paralysis.
Severity of facial paralysis
A six-point scale is used to determine the severity of facial paralysis. Grade I means that there is no interference with the facial nerves. Grade VI, on the other hand, is complete paralysis. Levels II and III are treacherous: the facial nerve is slightly damaged here. However, the lesion does not yet visibly disfigure the face and is thus sometimes only recognized at a late stage.
Therapy of facial paralysis
In the case of Bell’s palsy, the chances of recovery are good: even without treatment, the facial paralysis heals without consequences in around 85 percent of those affected. With cortisone therapy, it even disappears in up to 90 percent of patients. The healing period is between three and six weeks, but can also be up to six months in a severe form.
Facial paralysis: what you can do yourself
Most people feel panic when facial paralysis suddenly strikes. Even the relatives often feel helpless. Most people first think of a stroke.
Stroke test: FAST
Whether symptoms such as a sudden hemiplegia in the face or sudden speech disorders )see above actually indicate a stroke, lay people can assess using the FAST test:
- Arms: Have the affected person raise both arms with the inside of the hand facing up. If one half of the body is paralyzed, this will not work.
- Speech: The affected person must repeat a simple sentence understandably and without errors. If this is not successful, it may be a sign of a stroke.
- Time: If at least one of these tests is positive, you should immediately call an emergency physician and administer first aid.
How to act in case of a positive FAST test
- Stay with the sufferer, talk to them and reassure them – they are often confused and very frightened.
- Avoid dangers: Remove dentures, loosen clothing, do not give anything to drink or eat (paralysis-related swallowing disorders can cause the patient to choke).
- If the affected person is conscious, you should position him or her with the upper body raised – the angle between the floor and the back should be around 30 degrees.
- Check breathing and pulse! If neither of these can be detected in an unconscious person, you must start resuscitation immediately.
