Facial nerve paralysis

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Facial nerve paralysis
Other namesFacial palsy, prosopoplegia [1]
Paralisis facialMOCHE.jpg
Moche culture representation of facial paralysis. 300 AD, Larco Museum Collection, Lima, Peru
Specialty Neurology

Facial nerve paralysis is a common problem that involves the paralysis of any structures innervated by the facial nerve. The pathway of the facial nerve is long and relatively convoluted, so there are a number of causes that may result in facial nerve paralysis. [2] The most common is Bell's palsy, [3] [4] a disease of unknown cause that may only be diagnosed by exclusion of identifiable serious causes.

Contents

Signs and symptoms

Facial nerve paralysis is characterised by facial weakness, usually only in one side of the face, with other symptoms possibly including loss of taste, hyperacusis and decreased salivation and tear secretion[ ambiguous ]. Other signs may be linked to the cause of the paralysis, such as vesicles in the ear, which may occur if the facial palsy is due to shingles. Symptoms may develop over several hours. [5] : 1228  Acute facial pain radiating from the ear may precede the onset of other symptoms. [6] : 2585 

Causes

Bell's palsy

Bell's palsy is the most common cause of acute facial nerve paralysis. [3] [4] There is no known cause of Bell's palsy, [5] [6] although it has been associated with herpes simplex infection. Bell's palsy may develop over several days, and may last several months, in the majority of cases recovering spontaneously. It is typically diagnosed clinically, in patients with no risk factors for other causes, without vesicles in the ear, and with no other neurological signs. Recovery may be delayed in the elderly, or those with a complete paralysis. Bell's palsy is often treated with corticosteroids. [5] [6]

Infection

Lyme disease, an infection caused by Borrelia burgdorferi bacteria and spread by ticks, can account for about 25% of cases of facial palsy in areas where Lyme disease is common. [7] In the U.S., Lyme is most common in the New England and Mid-Atlantic states and parts of Wisconsin and Minnesota, but it is expanding into other areas. [8] The first sign of about 80% of Lyme infections, typically one or two weeks after a tick bite, is usually an expanding rash that may be accompanied by headaches, body aches, fatigue, or fever. [9] In up to 10-15% of Lyme infections, facial palsy appears several weeks later, and may be the first sign of infection that is noticed, as the Lyme rash typically does not itch and is not painful. Lyme disease is treated with antibiotics. [10] [11]

Reactivation of varicella zoster virus, as well as being associated with Bell's palsy, may also be a direct cause of facial nerve palsy. Reactivation of latent virus within the geniculate ganglion is associated with vesicles affecting the ear canal, and termed Ramsay Hunt syndrome type 2. [6] In addition to facial paralysis, symptoms may include ear pain and vesicles, sensorineural hearing loss, and vertigo. Management includes antiviral drugs and oral steroids.

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 as this must be removed if present. Inflammation from the middle ear can spread to the canalis facialis of the temporal bone - through this canal travels the facial nerve together with the statoacoustisus nerve. In the case of inflammation the nerve is exposed to edema and subsequent high pressure, resulting in a periferic type palsy.

Trauma

In blunt trauma, the facial nerve is the most commonly injured cranial nerve. [12] 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 blood behind the tympanic membrane, sensory deafness, and vertigo; the latter two symptoms due to damage to vestibulocochlear nerve and the inner ear. Longitudinal fracture in the vertical plane present a lower likelihood of paralysis (20%). Patients may present with blood coming out of the external auditory meatus), tympanic membrane tear, fracture of external auditory canal, and conductive hearing loss. In patients with mild injuries, 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, congenital cholesteatomas, hemangiomas, acoustic neuromas, parotid gland neoplasms, or metastases of other tumours. [13] [14]

Often, since facial neoplasms have such an intimate relationship with the facial nerve, removing tumors in this region becomes perplexing as the physician is unsure how to manage the tumor without causing even more palsy. Typically, benign tumors should be removed in a fashion that preserves the facial nerve, while malignant tumors should always be resected along with large areas of tissue around them, including the facial nerve. While this will inevitably lead to facial paralysis, safe removal of a malignant neoplasm is vital for patient survival. After tumor removal, the facial nerve can be reinnervated with techniques such as cross-facial nerve grafting, nerve transfers and end-to-end nerve repair. [15] Alternative treatment methods include muscle transfer techniques, such as the gracilis free muscle transfer [16] or static procedures.

Patients with facial nerve paralysis resulting from tumours 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 tumour, and it should be managed accordingly.

Other neoplastic causes include leptomeningeal carcinomatosis.

Stroke

Central facial palsy can be caused by a lacunar infarct affecting fibers in the internal capsule going to the nucleus. The facial nucleus itself can be affected by infarcts of the pontine arteries. Unlike peripheral facial palsy, central facial palsy does not affect the forehead, because the forehead is served by nerves coming from both motor cortexes. [7]

Other

Other causes may include:

Diagnosis

A medical history and physical examination, including a neurological examination, are needed for diagnosis. The first step is to observe what parts of the face do not move normally when the person tries to smile, blink, or raise the eyebrows. If the forehead wrinkles normally, a diagnosis of central facial palsy is made, and the person should be evaluated for stroke. [7] Otherwise, the diagnosis is peripheral facial palsy, and its cause needs to be identified, if possible. Ramsey Hunt's syndrome causes pain and small blisters in the ear on the same side as the palsy. Otitis media, trauma, or post-surgical complications may alternatively become apparent from history and physical examination. If there is a history of trauma, or a tumour is suspected, a CT scan or MRI may be used to clarify its impact. Blood tests or x-rays may be ordered depending on suspected causes. [6] The likelihood that the facial palsy is caused by Lyme disease should be estimated, based on recent history of outdoor activities in likely tick habitats during warmer months, recent history of rash or symptoms such as headache and fever, and whether the palsy affects both sides of the face (much more common in Lyme than in Bell's palsy). If that likelihood is more than negligible, a serological test for Lyme disease should be performed. If the test is positive, the diagnosis is Lyme disease. If no cause is found, the diagnosis is Bell's Palsy.

Classification

The facial nerve Cranial nerve VII.svg
The facial nerve

Facial nerve paralysis may be divided into supranuclear and infranuclear lesions. In a clinical setting, other commonly used classifications include: intra-cranial and extra-cranial; acute, subacute and chronic duration. [17]

Supranuclear and nuclear lesions

Central facial palsy can be caused by a lacunar infarct affecting fibers in the internal capsule going to the nucleus. The facial nucleus itself can be affected by infarcts of the pontine arteries. These are corticobulbar fibers travelling in internal capsule.

Infranuclear lesions

Infranuclear lesions refer to the majority of causes of facial palsy.

Treatment

If an underlying cause has been found for the facial palsy, it should be treated. If it is estimated that the likelihood that the facial palsy is caused by Lyme disease exceeds 10%, empiric therapy with antibiotics should be initiated, without corticosteroids, and reevaluated upon completion of laboratory tests for Lyme disease. [7] All other patients should be treated with corticosteroids and, if the palsy is severe, antivirals. Facial palsy is considered severe if the person is unable to close the affected eye completely or the face is asymmetric even at rest. Corticosteroids initiated within three days of Bell's palsy onset have been found to increase chances of recovery, reduce time to recovery, and reduce residual symptoms in case of incomplete recovery. [7] However, for facial palsy caused by Lyme disease, corticosteroids have been found in some studies to harm outcomes. [7] Other studies have found antivirals to possibly improve outcomes relative to corticosteroids alone for severe Bell's palsy. [7] In those whose blinking is disrupted by the facial palsy, frequent use of artificial tears while awake is recommended, along with ointment and a patch or taping the eye closed when sleeping. [7] [18] Several surgical treatment options exist to restore symmetry to the paralyzed face in patients where function does not return (see section Tumors above).

Prognostic

A study followed thirty individuals with facial paralysis following a stroke. Six months after the onset of paralysis, two-thirds of the patients had fully recovered or only had mild facial paralysis. [19]

In the case of Bell's palsy, 71% of individuals fully recover without any sequelae. Additionally, the majority of individuals begin to recover within seven days after the onset of paralysis. [20]

Related Research Articles

<span class="mw-page-title-main">Otorhinolaryngology</span> Medical specialty of the head and neck

Otorhinolaryngology is a surgical subspecialty within medicine that deals with the surgical and medical management of conditions of the head and neck. Doctors who specialize in this area are called otorhinolaryngologists, otolaryngologists, head and neck surgeons, or ENT surgeons or physicians. Patients seek treatment from an otorhinolaryngologist for diseases of the ear, nose, throat, base of the skull, head, and neck. These commonly include functional diseases that affect the senses and activities of eating, drinking, speaking, breathing, swallowing, and hearing. In addition, ENT surgery encompasses the surgical management of cancers and benign tumors and reconstruction of the head and neck as well as plastic surgery of the face, scalp, and neck.

<span class="mw-page-title-main">Ramsay Hunt syndrome type 2</span> Presentation of shingles in the geniculate ganglion

Ramsay Hunt syndrome type 2, commonly referred to simply as Ramsay Hunt syndrome (RHS) and also known as herpes zoster oticus, is inflammation of the geniculate ganglion of the facial nerve as a late consequence of varicella zoster virus (VZV). In regard to the frequency, less than 1% of varicella zoster infections involve the facial nerve and result in RHS. It is traditionally defined as a triad of ipsilateral facial paralysis, otalgia, and vesicles close to the ear and auditory canal. Due to its proximity to the vestibulocochlear nerve, the virus can spread and cause hearing loss, tinnitus, and vertigo. It is common for diagnoses to be overlooked or delayed, which can raise the likelihood of long-term consequences. It is more complicated than Bell's palsy. Therapy aims to shorten its overall length, while also providing pain relief and averting any consequences.

<span class="mw-page-title-main">Bell's palsy</span> Facial paralysis resulting from dysfunction in the cranial nerve VII (facial nerve)

Bell's palsy is a type of facial paralysis that results in a temporary inability to control the facial muscles on the affected side of the face. In most cases, the weakness is temporary and significantly improves over weeks. Symptoms can vary from mild to severe. They may include muscle twitching, weakness, or total loss of the ability to move one or, in rare cases, both sides of the face. Other symptoms include drooping of the eyebrow, a change in taste, and pain around the ear. Typically symptoms come on over 48 hours. Bell's palsy can trigger an increased sensitivity to sound known as hyperacusis.

<span class="mw-page-title-main">Abducens nerve</span> Cranial nerve VI, for eye movements

The abducens nerve or abducent nerve, also known as the sixth cranial nerve, cranial nerve VI, or simply CN VI, is a cranial nerve in humans and various other animals that controls the movement of the lateral rectus muscle, one of the extraocular muscles responsible for outward gaze. It is a somatic efferent nerve.

<span class="mw-page-title-main">Ear pain</span> Pain in the ear

Ear pain, also known as earache or otalgia, is pain in the ear. Primary ear pain is pain that originates from the ear. Secondary ear pain is a type of referred pain, meaning that the source of the pain differs from the location where the pain is felt.

<span class="mw-page-title-main">Neuritis</span> Inflammation of a nerve or generally any part of the nervous system

Neuritis, from the Greek νεῦρον), is inflammation of a nerve or the general inflammation of the peripheral nervous system. Inflammation, and frequently concomitant demyelination, cause impaired transmission of neural signals and leads to aberrant nerve function. Neuritis is often conflated with neuropathy, a broad term describing any disease process which affects the peripheral nervous system. However, neuropathies may be due to either inflammatory or non-inflammatory causes, and the term encompasses any form of damage, degeneration, or dysfunction, while neuritis refers specifically to the inflammatory process.

<span class="mw-page-title-main">Sixth nerve palsy</span> Medical condition

Sixth nerve palsy, or abducens nerve palsy, is a disorder associated with dysfunction of cranial nerve VI, which is responsible for causing contraction of the lateral rectus muscle to abduct the eye. The inability of an eye to turn outward, results in a convergent strabismus or esotropia of which the primary symptom is diplopia in which the two images appear side-by-side. Thus, the diplopia is horizontal and worse in the distance. Diplopia is also increased on looking to the affected side and is partly caused by overaction of the medial rectus on the unaffected side as it tries to provide the extra innervation to the affected lateral rectus. These two muscles are synergists or "yoke muscles" as both attempt to move the eye over to the left or right. The condition is commonly unilateral but can also occur bilaterally.

<span class="mw-page-title-main">Cavernous sinus thrombosis</span> Medical condition

Cavernous sinus thrombosis (CST) is the formation of a blood clot within the cavernous sinus, a cavity at the base of the brain which drains deoxygenated blood from the brain back to the heart. This is a rare disorder and can be of two types–septic cavernous thrombosis and aseptic cavernous thrombosis. The most common form is septic cavernous sinus thrombosis. The cause is usually from a spreading infection in the nose, sinuses, ears, or teeth. Staphylococcus aureus and Streptococcus are often the associated bacteria.

<span class="mw-page-title-main">Fazio–Londe disease</span> Medical condition

Fazio–Londe disease (FLD), also called progressive bulbar palsy of childhood, is a very rare inherited motor neuron disease of children and young adults and is characterized by progressive paralysis of muscles innervated by cranial nerves. FLD, along with Brown–Vialetto–Van Laere syndrome (BVVL), are the two forms of infantile progressive bulbar palsy, a type of progressive bulbar palsy in children.

<span class="mw-page-title-main">Foix–Chavany–Marie syndrome</span> Medical condition

Foix–Chavany–Marie syndrome (FCMS), also known as bilateral opercular syndrome, is a neuropathological disorder characterized by paralysis of the facial, tongue, pharynx, and masticatory muscles of the mouth that aid in chewing. The disorder is primarily caused by thrombotic and embolic strokes, which cause a deficiency of oxygen in the brain. As a result, bilateral lesions may form in the junctions between the frontal lobe and temporal lobe, the parietal lobe and cortical lobe, or the subcortical region of the brain. FCMS may also arise from defects existing at birth that may be inherited or nonhereditary. Symptoms of FCMS can be present in a person of any age and it is diagnosed using automatic-voluntary dissociation assessment, psycholinguistic testing, neuropsychological testing, and brain scanning. Treatment for FCMS depends on the onset, as well as on the severity of symptoms, and it involves a multidisciplinary approach.

Vocal cord paresis, also known as recurrent laryngeal nerve paralysis or vocal fold paralysis, is an injury to one or both recurrent laryngeal nerves (RLNs), which control all intrinsic muscles of the larynx except for the cricothyroid muscle. The RLN is important for speaking, breathing and swallowing.

<span class="mw-page-title-main">Tolosa–Hunt syndrome</span> Medical condition

Tolosa–Hunt syndrome is a rare disorder characterized by severe and unilateral headaches with orbital pain, along with weakness and paralysis (ophthalmoplegia) of certain eye muscles.

Synkinesis is a neurological symptom in which a voluntary muscle movement causes the simultaneous involuntary contraction of other muscles. An example might be smiling inducing an involuntary contraction of the eye muscles, causing a person to squint when smiling. Facial and extraocular muscles are affected most often; in rare cases, a person's hands might perform mirror movements.

The cerebellopontine angle syndrome is a distinct neurological syndrome of deficits that can arise due to the closeness of the cerebellopontine angle to specific cranial nerves. Indications include unilateral hearing loss (85%), speech impediments, disequilibrium, tremors or other loss of motor control. The cerebellopontine angle cistern is a subarachnoid cistern formed by the cerebellopontine angle that lies between the cerebellum and the pons. It is filled with cerebrospinal fluid and is a common site for the growth of acoustic neuromas or schwannomas.

<span class="mw-page-title-main">Posterior spinal artery syndrome</span> Human spinal cord disorder

Posterior spinal artery syndrome(PSAS), also known as posterior spinal cord syndrome, is a type of incomplete spinal cord injury. PSAS is the least commonly occurring of the six clinical spinal cord injury syndromes, with an incidence rate of less than 1%.

<span class="mw-page-title-main">Cranial nerve disease</span> Impaired functioning of one of the twelve cranial nerves

Cranial nerve disease is an impaired functioning of one of the twelve cranial nerves. Although it could theoretically be considered a mononeuropathy, it is not considered as such under MeSH.

Heerfordt syndrome is a rare manifestation of sarcoidosis. The symptoms include inflammation of the eye (uveitis), swelling of the parotid gland, chronic fever, and in some cases, palsy of the facial nerves.

<span class="mw-page-title-main">Otitis externa</span> Inflammation of the ear canal

Otitis externa, also called swimmer's ear, is inflammation of the ear canal. It often presents with ear pain, swelling of the ear canal, and occasionally decreased hearing. Typically there is pain with movement of the outer ear. A high fever is typically not present except in severe cases.

Alternating hemiplegia is a form of hemiplegia that has an ipsilateral cranial nerve palsies and contralateral hemiplegia or hemiparesis of extremities of the body. The disorder is characterized by recurrent episodes of paralysis on one side of the body. There are multiple forms of alternating hemiplegia, Weber's syndrome, middle alternating hemiplegia, and inferior alternating hemiplegia. This type of syndrome can result from a unilateral lesion in the brainstem affecting both upper motor neurons and lower motor neurons. The muscles that would receive signals from these damaged upper motor neurons result in spastic paralysis. With a lesion in the brainstem, this affects the majority of limb and trunk muscles on the contralateral side due to the upper motor neurons decussation after the brainstem. The cranial nerves and cranial nerve nuclei are also located in the brainstem making them susceptible to damage from a brainstem lesion. Cranial nerves III (Oculomotor), VI (Abducens), and XII (Hypoglossal) are most often associated with this syndrome given their close proximity with the pyramidal tract, the location which upper motor neurons are in on their way to the spinal cord. Damages to these structures produce the ipsilateral presentation of paralysis or palsy due to the lack of cranial nerve decussation before innervating their target muscles. The paralysis may be brief or it may last for several days, many times the episodes will resolve after sleep. Some common symptoms of alternating hemiplegia are mental impairment, gait and balance difficulties, excessive sweating and changes in body temperature.

Facial nerve decompression is a type of nerve decompression surgery where abnormal compression on the facial nerve is relieved.

References

  1. ↑ "prosopoplegia". The Free Dictionary. Retrieved 1 January 2018.
  2. ↑ "Facial Nerve" . Retrieved 22 November 2009.
  3. 1 2 Fuller, G; Morgan, C (31 March 2016). "Bell's palsy syndrome: mimics and chameleons". Practical Neurology. 16 (6): 439–44. doi:10.1136/practneurol-2016-001383. PMID   27034243. S2CID   4480197.
  4. 1 2 Dickson, Gretchen (2014). Primary Care ENT, An Issue of Primary Care: Clinics in Office Practice. Elsevier Health Sciences. p. 138. ISBN   978-0323287173. Archived from the original on 20 August 2016.
  5. 1 2 3 Colledge, Nicki R.; Walker, Brian R.; Ralston, Stuart H., eds. (2010). Davidson's principles and practice of medicine. illust. Robert Britton (21st ed.). Edinburgh: Churchill Livingstone/Elsevier. ISBN   978-0-7020-3084-0.
  6. 1 2 3 4 5 6 7 8 Fauci, Anthony S.; Harrison, T. R., eds. (2008). Harrison's principles of internal medicine (17th ed.). New York: McGraw-Hill Medical. ISBN   978-0-07-147693-5.
  7. 1 2 3 4 5 6 7 8 Garro A, Nigrovic LE (May 2018). "Managing Peripheral Facial Palsy". Annals of Emergency Medicine. 71 (5): 618–623. doi: 10.1016/j.annemergmed.2017.08.039 . PMID   29110887.
  8. ↑ "Lyme Disease Data and surveillance". Lyme Disease. Centers for Disease Control and Prevention. Retrieved 12 April 2019.
  9. ↑ "Lyme disease rashes and look-alikes". Lyme Disease. Centers for Disease Control and Prevention. Retrieved 18 April 2019.
  10. ↑ Wright WF, Riedel DJ, Talwani R, Gilliam BL (June 2012). "Diagnosis and management of Lyme disease". American Family Physician. 85 (11): 1086–93. PMID   22962880. Archived from the original on 27 September 2013.
  11. ↑ Shapiro ED (May 2014). "Clinical practice. Lyme disease" (PDF). The New England Journal of Medicine. 370 (18): 1724–1731. doi:10.1056/NEJMcp1314325. PMC   4487875 . PMID   24785207. Archived from the original (PDF) on 19 October 2016.
  12. ↑ Cools MJ, Carneiro KA (April 2018). "Facial nerve palsy following mild mastoid trauma on trampoline". Am J Emerg Med. 36 (8): 1522.e1–1522.e3. doi:10.1016/j.ajem.2018.04.034. PMID   29861376. S2CID   44106089.
  13. ↑ Thompson AL, Bharatha A, Aviv RI, Nedzelski J, Chen J, Bilbao JM, Wong J, Saad R, Symons SP (July 2009). "Chondromyoid fibroma of the mastoid facial nerve canal mimicking a facial nerve schwannoma". Laryngoscope. 119 (7): 1380–1383. doi:10.1002/lary.20486. PMID   19507235. S2CID   34800452.
  14. ↑ Thompson AL, Aviv RI, Chen JM, Nedzelski JM, Yuen HW, Fox AJ, Bharatha A, Bartlett ES, Symons SP (December 2009). "MR imaging of facial nerve schwannoma". Laryngoscope. 119 (12): 2428–2436. doi: 10.1002/lary.20644 . PMID   19780031. S2CID   24237419.
  15. ↑ Rodríguez-Lorenzo, Andrés; Tzou, Chieh-Han, eds. (2021). Facial palsy : techniques for reanimation of the paralyzed face. Cham, Switzerland. doi:10.1007/978-3-030-50784-8. ISBN   978-3-030-50784-8. S2CID   235205923 . Retrieved 11 October 2022.{{cite book}}: CS1 maint: location missing publisher (link)
  16. ↑ Bui, Mai-Anh; Goh, Raymond; Vu, Trung-Truc (11 July 2019). "Dynamic Reanimation of Smile in Facial Paralysis with Gracilis Functioning Free Muscle Flap Innervated by Masseteric Nerve: The First Vietnamese Series". International Microsurgery Journal (Imj). 3 (2). doi: 10.24983/scitemed.imj.2019.00116 . S2CID   199045428.
  17. ↑ [ permanent dead link ] The Plastics Fella Guide to Facial Nerve Anatomy
  18. ↑ Michelle Stephenson (4 October 2012). "OTC Drops: Telling the Tears Apart". Review of Ophtalmology. Jobson Medical Information LLC. Retrieved 16 April 2019.
  19. ↑ Svensson, B. H.; Christiansen, L. S.; Jepsen, E. (7 December 1992). "[Treatment of central facial nerve paralysis with electromyography biofeedback and taping of cheek. A controlled clinical trial]". Ugeskrift for Laeger. 154 (50): 3593–3596. ISSN   0041-5782. PMID   1471279.
  20. ↑ Holland, N. Julian; Bernstein, Jonathan M. (9 April 2014). "Bell's palsy". BMJ Clinical Evidence. 2014: 1204. ISSN   1752-8526. PMC   3980711 . PMID   24717284.
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