Editor-In-Chief: C. Michael Gibson, M.S., M.D. [2]
Causes
Common Causes
Bell's palsy
Bell's palsy is the most common cause of acute facial nerve paralysis (>80%). Previously considered idiopathic, it has been recently linked to herpes zosterof the facial nerve (rarely Lyme disease).
Bell's palsy is an exclusion diagnosis. Some factors that tend to rule out Bell's palsy include:
- Recurrent paralysis
- Slowly progressive paralysis (The onset of Bell's palsy is very sudden)
- Twitching
- Associated symptoms (either cochlear or neurologic)
Bell's palsy is believed in the most recent studies to be due to herpes virus. Other proposed etiologies include vascular problems in the inner ear. Treatment includesteroids and antivirals.
Trauma
Physical trauma, especially fractures of the temporal bone, may also cause acute facial nerve paralysis. Understandably, the likelihood of facial paralysis after trauma depends on the location of the trauma. Most commonly, facial paralysis follows temporal bone fractures, though the likelihood depends on the type of fracture.
Transverse fractures in the horizontal plane present the highest likelihood of facial paralysis (40-50%). Patients may also present with hemotympanum (blood behind the tympanic membrane), sensory deafness, and vertigo – the latter two symptoms due to damage to vestibulocochlear nerve (cranial nerveVIII) and the inner ear. Longitudinal fracture in the vertical plane present a lower likelihood of paralysis (20%). Patients may present with hematorrhea (bloodcoming out of the external auditory meatus), tympanic membrane tear, fracture of external auditory canal, and conductive hearing loss.
Traumatic injuries can be assessed by computed tomography (CT) and nerve conduction studies (ENoG). In patients with mild injury, management is the same as with Bell's palsy – protect the eyes and wait. In patients with severe injury, progress is followed with nerve conduction studies. If nerve conduction studies show a large (>90%) change in nerve conduction, the nerve should be decompressed. The facial paralysis can follow immediately the trauma due to direct damage to the facial nerve, in such cases a surgical treatment may be attempted. In other cases the facial paralysis can occur a long time after the trauma due to oedema and inflammation. In those cases steroids can be a good help.
Tumors
A tumor compressing the facial nerve anywhere along its complex pathway can result in facial paralysis. Common culprits are facial neuromas, congenitalcholesteatomas, hemangiomas, acoustic neuromas, parotid gland neoplasms, or metastases of other tumors.
Patients with facial nerve paralysis resulting from tumors usually present with a progressive, twitching paralysis, other neurological signs, or a recurrent Bell's palsy-type presentation.
The latter should always be suspicious, as Bell's palsy should not recur. A chronically discharging ear must be treated as a cholesteatoma until proven otherwise; hence, there must be immediate surgical exploration.
Computed tomography (CT) or magnetic resonance (MR) imaging should be used to identify the location of the tumor, and it should be managed accordingly.
Herpes zoster oticus
Herpes zoster oticus is essentially a herpes zoster infection that affects cranial nerves VII (facial nerve) and VIII (vestibulocochlear nerve).
Patients present with facial paralysis, ear pain, vesicles, sensorineural hearing loss, and vertigo.
Management includes antivirals and oral steroids.
Acute and chronic otitis media
Otitis media is an infection in the middle ear, which can spread to the facial nerve and inflame it, causing compression of the nerve in its canal.
Antibiotics are used to control the otitis media, and other options include a wide myringotomy (an incision in the tympanic membrane) or decompression if the patient does not improve
Chronic otitis media usually presents in an ear with chronic discharge (otorrhea), or hearing loss, with or without ear pain (otalgia). Once suspected, there should be immediate surgical exploration to determine if a cholesteatoma has formed and must be removed.
Neurosarcoidosis
Facial nerve paralysis, sometimes bilateral, is a common manifestation of neurosarcoidosis (sarcoidosis of the nervous system), itself a rare condition.
Causes by Organ System
| Cardiovascular
|
Aneurysm, Arteriosclerosis, Carotid artery aneurysm, Cayler cardiofacial syndrome, Cerebral infarction, Cerebral vascular accidents, DiGeorge syndrome, Embolization, Foix–Alajouanine syndrome, Foville syndrome, Hemangioblastoma, Hemangioma of tympanum, Hypertension, Ischemic mononeuropathy, Polyarteritis nodosa, Pontine infarction, Stroke, Temporal arteritis, Transient ischemic attack, Vertebrobasilar dolichoectasia, Wallenberg's syndrome
|
| Chemical/Poisoning
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Arsenic intoxication, Carbon monoxide, Chemical poisoning, Cresylic acid, Ethylene glycol
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| Dental
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Dental procedure
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| Dermatologic
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Facial hemiatrophy, Hidradenoma, Melkersson-Rosenthal-Schuermann syndrome, Neurofibromatosis, Systemic sclerosis, Thrombotic thrombocytopenic purpura
|
| Drug Side Effect
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Cidofovir, Pergolide, Thalidomide
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| Ear Nose Throat
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Acoustic neuroma, Acquired cholesteatoma, Acute otitis media, Adenoid cystic carcinoma, Adenoidectomy, Anomalous sigmoid sinus, Benign lesions of parotid, CHARGE syndrome, Chronic otitis media, Congenital cholesteatoma, Deafness, conductive stapedial, with ear malformation and facial palsy, Diptheria, Ear surgery, Enterovirus 70, External otitis, Goldenhar's syndrome, Heerfordt-Waldenström syndrome, Hemangioma of tympanum, Herpes zoster oticus, Middle-ear infection, Otitis media, Parotid gland neoplasm, Parotid gland surgery, Parotid tumor, Penetrating injury to middle ear, Posttonsillectormy, Ramsay Hunt syndrome type II, Salivary gland cancer, Suppurative otitis media, Uveoparotid fever
|
| Endocrine
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Diabetes mellitus, DiGeorge syndrome, Hyperthyroidism
|
| Environmental
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Barotrauma
|
| Gastroenterologic
|
No underlying causes
|
| Genetic
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Albers-Schonberg disease, Alternating hemiplegia, Beta-ketothiolase deficiency, CHARGE syndrome, Craniodiaphyseal dysplasia, Craniometaphyseal dysplasia, Deafness, conductive stapedial, with ear malformation and facial palsy, DiGeorge syndrome, Dystophia myotonica, Facioscapulohumeral muscular dystrophy, Finnish type amyloidosis, Goldenhar's syndrome, Hereditary congenital facial paresis 1, Hereditary congenital facial paresis 2, Hereditary hypertrophic neuropathy, Melkersson-Rosenthal-Schuermann syndrome, Moebius syndrome, Myotonic dystrophy, Osteopathia striata with cranial sclerosis, Osteopetrosis, Trisomy 13, Trisomy 18
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| Hematologic
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Hand-Schuller-Christian disease, Leukemia, Lymphoma, Temporal bone leukemia, Thrombotic thrombocytopenic purpura
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| Iatrogenic
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Adenoidectomy, Antitetanus serum, Ear surgery, Iontophoresis, Mandibular block anesthesia, Mastoid surgery, Parotid gland surgery, Postimmunization, Posttonsillectormy, Ramsay Hunt syndrome type II, Vaccine treatment for rabies
|
| Infectious Disease
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Acquired immune deficiency syndrome, Acute hemorrhagic conjunctivitis, Acute otitis media, Bell's palsy, Borrelia burgdorferi, Botulism, Cat scratch disease, Chickenpox, Chronic otitis media, Coxsackievirus, Diptheria, Enterovirus 70, External otitis, Geniculate herpes zoster, Gnathostomiasis, Gummatous meningitis, Herpes simplex virus, Herpes zoster oticus, Herpes zoster, Infectious mononucleosis, Influenza, Lepromatous leprosy, Lyme disease, Malaria, Mastoiditis, Middle-ear infection, Mucormycosis, Mumps, Otitis media, Poliomyelitis, Shingles, Suppurative otitis media, Syphilis, Tuberculosis
|
| Musculoskeletal/Orthopedic
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Albers-Schonberg disease, Basal skull fracture, Cayler cardiofacial syndrome, Craniodiaphyseal dysplasia, Craniometaphyseal dysplasia, Dystophia myotonica, Facioscapulohumeral muscular dystrophy, Fibrous dysplasia, Hand-Schuller-Christian disease, Mastoid surgery, Mastoiditis, Myasthenia gravis, Myopathy, Myotonic dystrophy, Osteopathia striata with cranial sclerosis, Osteopetrosis, Poland's syndrome, Rhabdomyosarcoma, Sclerotosis, Skull fracture, Temporal bone fracture, Temporal bone leukemia, Tumor of the petrous bone
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| Neurologic
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Acoustic neuroma, Alternating hemiplegia, Bell's palsy, Beta-ketothiolase deficiency, Bickerstaff's brainstem encephalitis, Botulism, Cerebral contusion, Cerebral infarction, Cerebral tumor, Cerebral vascular accidents, Degenerative cerebral disease, Encephalitis, Facial hemiatrophy, Facial nerve tumor, Facial neuroma, Foix–Alajouanine syndrome, Foville syndrome, Geniculate herpes zoster, Glioma, Glomus jugulare tumor, Guillain-Barre syndrome, Gummatous meningitis, Heerfordt-Waldenström syndrome, Hereditary hypertrophic neuropathy, Herpes zoster oticus, Intracranial space-occupying lesion, Iontophoresis, Ischemic mononeuropathy, Lepromatous leprosy, Lissauer's paralysis, Mandibular block anesthesia, Melkersson-Rosenthal-Schuermann syndrome, Meningioma, Miehlke syndrome, Millard-Gubler syndrome, Miller Fisher syndrome, Moebius syndrome, Motor neuron disease, Multiple sclerosis, Myasthenia gravis, Neurofibromatosis, Opercular syndrome, Paraganglioma, Poliomyelitis, Polyneuritis cranialis, Polyneuritis, Polyradiculoneuropathy, Pontine infarction, Schwannoma, Seventh nerve tumor, Stroke, Temporal lobe epilepsy, Tetanus, Transient ischemic attack, Uveoparotid fever, Vertebrobasilar dolichoectasia, Wallenberg's syndrome
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| Nutritional/Metabolic
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Vitamin A deficiency
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| Obstetric/Gynecologic
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Difficult labour, Pregnancy
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| Oncologic
|
Acoustic neuroma, Adenoid cystic carcinoma, Carcinoma, Cerebral tumor, Cylindroma, Facial nerve tumor, Facial neuroma, Glioma, Glomus jugulare tumor, Hand-Schuller-Christian disease, Hemangioblastoma, Leukemia, Lymphoma, Meningioma, Metastatic neoplasm, Neoplasm, Neurofibromatosis, Paraganglioma, Parotid gland neoplasm, Parotid tumor, Rhabdomyosarcoma, Salivary gland cancer, Schwannoma, Seventh nerve tumor, Temporal bone leukemia, Teratogenesis, Teratoma, Tumor of the petrous bone
|
| Ophthalmologic
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Acute hemorrhagic conjunctivitis, Heerfordt-Waldenström syndrome, Uveoparotid fever|-
|
| Overdose/Toxicity
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Alcoholism
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| Psychiatric
|
No underlying causes
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| Pulmonary
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No underlying causes
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| Renal/Electrolyte
|
No underlying causes
|
| Rheumatology/Immunology/Allergy
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Acquired immune deficiency syndrome, Antitetanus serum, Bickerstaff's brainstem encephalitis, Facial hemiatrophy, Guillain-Barre syndrome, Miller Fisher syndrome, Multiple sclerosis, Myasthenia gravis, Polyarteritis nodosa, Postimmunization, Sarcoidosis, Systemic sclerosis, Temporal arteritis, Thrombotic thrombocytopenic purpura, Vaccine treatment for rabies
|
| Sexual
|
No underlying causes
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| Trauma
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Barotrauma, Basal skull fracture, Cerebral contusion, Difficult labour, Facial injury, Head injury, Penetrating injury to middle ear, Skull fracture, Temporal bone fracture, Trauma
|
| Urologic
|
No underlying causes
|
| Miscellaneous
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Amyloidosis, Finnish type amyloidosis, Lightning, Poland's syndrome, Sarcoidosis, Sarcoma
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Causes in Alphabetical Order
References