Bell's palsy is a type of facial paralysis that results in an inability to control the facial muscles on the affected side. Symptoms can vary from mild to severe. They may include muscle twitching, weakness, or total loss of the ability to move one or rarely both sides of the face. Other symptoms include drooping of the eyelid, a change in taste, pain around the ear, and increased sensitivity to sound. Typically symptoms come on over 48 hours.
The cause of Bell's palsy is unknown. Risk factors include diabetes, a recent upper respiratory tract infection, and pregnancy. It results from a dysfunction of cranial nerve VII (the facial nerve). Many believe that this is due to a viral infection that results in swelling. Diagnosis is based on a person's appearance and ruling out other possible causes. Other conditions that can cause facial weakness include brain tumor, stroke, Ramsay Hunt syndrome, myasthenia gravis, and Lyme disease.
The condition normally gets better by itself with most achieving normal or near-normal function. Corticosteroids have been found to improve outcomes, while antiviral medications may be of a small additional benefit. The eye should be protected from drying up with the use of eye drops or an eyepatch. Surgery is generally not recommended. Often signs of improvement begin within 14 days, with complete recovery within six months. A few may not recover completely or have a recurrence of symptoms.
Bell's palsy is the most common cause of one-sided facial nerve paralysis (70%). It occurs in 1 to 4 per 10,000 people per year. About 1.5% of people are affected at some point in their life. It most commonly occurs in people between ages 15 and 60. Males and females are affected equally. It is named after Scottish surgeon Charles Bell (1774–1842), who first described the connection of the facial nerve to the condition.
|A person attempting to show his teeth and raise his eyebrows with Bell's palsy on his right side (left side of the image; notice how the forehead is not spared).|
|Symptoms||Inability to move the facial muscles on one side, change in taste, pain around the ear|
|Usual onset||Over 48 hours|
|Risk factors||Diabetes, recent upper respiratory tract infection|
|Diagnostic method||Based on symptoms|
|Differential diagnosis||Brain tumor, stroke, Ramsay Hunt syndrome, Lyme disease|
|Treatment||Corticosteroids, eye drops, eyepatch|
|Prognosis||Most recover completely|
|Frequency||1–4 per 10,000 per year|
The facial nerve controls a number of functions, such as blinking and closing the eyes, smiling, frowning, lacrimation, salivation, flaring nostrils and raising eyebrows. It also carries taste sensations from the anterior two-thirds of the tongue, via the chorda tympani nerve (a branch of the facial nerve). Because of this, people with Bell's palsy may present with loss of taste sensation in the anterior 2/3 of the tongue on the affected side.
Although the facial nerve innervates the stapedius muscle of the middle ear (via the tympanic branch), sound sensitivity, causing normal sounds to be perceived as very loud, and dysacusis are possible but hardly ever clinically evident.
Although defined as a mononeuritis (involving only one nerve), people diagnosed with Bell's palsy may have "myriad neurological symptoms" including "facial tingling, moderate or severe headache/neck pain, memory problems, balance problems, ipsilateral limb paresthesias, ipsilateral limb weakness, and a sense of clumsiness" that are "unexplained by facial nerve dysfunction".
Some viruses are thought to establish a persistent (or latent) infection without symptoms, e.g., the varicella-zoster virus and Epstein–Barr viruses, both of the herpes family. Reactivation of an existing (dormant) viral infection has been suggested as a cause of acute Bell's palsy. This new activation could be triggered by trauma, environmental factors, and metabolic or emotional disorders.
Bell's palsy occurs due to a malfunction of the facial nerve (cranial nerve VII), which controls the muscles of the face. Facial palsy is typified by inability to control movement in the muscles of facial expression. The paralysis is of the infranuclear/lower motor neuron type.
It is thought that as a result of inflammation of the facial nerve, pressure is produced on the nerve where it exits the skull within its bony canal (the stylomastoid foramen), blocking the transmission of neural signals or damaging the nerve. Patients with facial palsy for which an underlying cause can be found are not considered to have Bell's palsy per se. Possible causes include tumor, meningitis, stroke, diabetes mellitus, head trauma and inflammatory diseases of the cranial nerves (sarcoidosis, brucellosis, etc.). In these conditions, the neurologic findings are rarely restricted to the facial nerve. Babies can be born with facial palsy. In a few cases, bilateral facial palsy has been associated with acute HIV infection.
In some research, the herpes simplex virus type 1 (HSV-1) has been identified in a majority of cases diagnosed as Bell's palsy via endoneurial fluid sampling. Other research, however, identified, out of a total of 176 cases diagnosed as Bell's palsy, HSV-1 in 31 cases (18 percent) and herpes zoster in 45 cases (26 percent).
In addition, HSV-1 infection is associated with demyelination of nerves. This nerve damage mechanism is different from the above-mentioned - that edema, swelling and compression of the nerve in the narrow bone canal is responsible for nerve damage. Demyelination may not even be directly caused by the virus, but by an unknown immune response.
Bell's palsy is a diagnosis of exclusion, meaning it is diagnosed by elimination of other reasonable possibilities. By definition, no specific cause can be determined. There are no routine lab or imaging tests required to make the diagnosis. The degree of nerve damage can be assessed using the House-Brackmann score.
One study found that 45% of patients are not referred to a specialist, which suggests that Bell's palsy is considered by physicians to be a straightforward diagnosis that is easy to manage.
Once the facial paralysis sets in, many people may mistake it as a symptom of a stroke; however, there are a few subtle differences. A stroke will usually cause a few additional symptoms, such as numbness or weakness in the arms and legs. And unlike Bell's palsy, a stroke will usually let patients control the upper part of their faces. A person with a stroke will usually have some wrinkling of their forehead.
One disease that may be difficult to exclude in the differential diagnosis is involvement of the facial nerve in infections with the herpes zoster virus. The major differences in this condition are the presence of small blisters, or vesicles, on the external ear and hearing disturbances, but these findings may occasionally be lacking (zoster sine herpete). Reactivation of existing herpes zoster infection leading to facial paralysis in a Bell's palsy type pattern is known as Ramsay Hunt syndrome type 2.
Lyme disease may produce facial palsy. Sometimes the facial palsy occurs at the same time as the classic erythema migrans rash. Other times, it occurs later. In areas where Lyme disease is common, it may be the cause of facial palsy in half of cases.
Steroids have been shown to be effective at improving recovery in Bell's palsy while antivirals have not. In those who are unable to close their eyes, eye protective measures are required. Management in during pregnancy is similar to the non pregnant.
Corticosteroids such as prednisone improve recovery at 6 months and are thus recommended. Early treatment (within 3 days after the onset) is necessary for benefit with a 14% greater probability of recovery.
One review found that antivirals (such as aciclovir) are ineffective in improving recovery from Bell's palsy beyond steroids alone in mild to moderate disease. Another review found a benefit when combined with corticosteroids but stated the evidence was not very good to support this conclusion.
They are commonly prescribed due to a theoretical link between Bell's palsy and the herpes simplex and varicella zoster virus. There is still the possibility that they might result in a benefit less than 7% as this has not been ruled out.
Physiotherapy can be beneficial to some individuals with Bell's palsy as it helps to maintain muscle tone of the affected facial muscles and stimulate the facial nerve. It is important that muscle re-education exercises and soft tissue techniques be implemented prior to recovery in order to help prevent permanent contractures of the paralyzed facial muscles. To reduce pain, heat can be applied to the affected side of the face. There is no high quality evidence to support the role of electrical stimulation for Bell's palsy.
Surgery may be able to improve outcomes in facial nerve palsy that has not recovered. A number of different techniques exist. Smile surgery or smile reconstruction is a surgical procedure that may restore the smile for people with facial nerve paralysis. It is unknown if early surgery is beneficial or harmful. Adverse effects include hearing loss which occurs in 3–15% of people. As of 2007 the American Academy of Neurology did not recommend surgical decompression.
The efficacy of acupuncture remains unknown because the available studies are of low quality (poor primary study design or inadequate reporting practices). There is very tentative evidence for hyperbaric oxygen therapy in severe disease.
Most people with Bell's palsy start to regain normal facial function within 3 weeks—even those who do not receive treatment. In a 1982 study, when no treatment was available, of 1,011 patients, 85% showed first signs of recovery within 3 weeks after onset. For the other 15%, recovery occurred 3–6 months later.
After a follow-up of at least one year or until restoration, complete recovery had occurred in more than two-thirds (71%) of all patients. Recovery was judged moderate in 12% and poor in only 4% of patients. Another study found that incomplete palsies disappear entirely, nearly always in the course of one month. The patients who regain movement within the first two weeks nearly always remit entirely. When remission does not occur until the third week or later, a significantly greater part of the patients develop sequelae. A third study found a better prognosis for young patients, aged below 10 years old, while the patients over 61 years old presented a worse prognosis.
Major complications of the condition are chronic loss of taste (ageusia), chronic facial spasm, facial pain and corneal infections. To prevent the latter, the eyes may be protected by covers, or taped shut during sleep and for rest periods, and tear-like eye drops or eye ointments may be recommended, especially for cases with complete paralysis. Where the eye does not close completely, the blink reflex is also affected, and care must be taken to protect the eye from injury.
Another complication can occur in case of incomplete or erroneous regeneration of the damaged facial nerve. The nerve can be thought of as a bundle of smaller individual nerve connections that branch out to their proper destinations. During regrowth, nerves are generally able to track the original path to the right destination—but some nerves may sidetrack leading to a condition known as synkinesis. For instance, regrowth of nerves controlling muscles attached to the eye may sidetrack and also regrow connections reaching the muscles of the mouth. In this way, movement of one also affects the other. For example, when the person closes the eye, the corner of the mouth lifts involuntarily.
Around 9% of patients have some sort of sequelae after Bell's palsy, typically the synkinesis already discussed, or spasm, contracture, tinnitus and/or hearing loss during facial movement or |crocodile tear syndrome. This is also called gustatolacrimal reflex or Bogorad's syndrome and involves the sufferer shedding tears while eating. This is thought to be due to faulty regeneration of the facial nerve, a branch of which controls the lacrimal and salivary glands. Gustatorial sweating can also occur.
The number of new cases of Bell's palsy ranges from about one to four cases per 10,000 population per year. The rate increases with age. Bell's palsy affects about 40,000 people in the United States every year. It affects approximately 1 person in 65 during a lifetime.
A range of annual incidence rates have been reported in the literature: 15, 24, and 25–53 (all rates per 100,000 population per year). Bell's palsy is not a reportable disease, and there are no established registries for people with this diagnosis, which complicates precise estimation.
Cornelis Stalpart van der Wiel (1620–1702) in 1683 gave an account of Bell's palsy and credited the Persian physician Ibn Sina (980–1037) for describing this condition before him. James Douglas (1675–1742) and Nicolaus Anton Friedreich (1761–1836) also described it.
A notable person with Bell's palsy is former Prime Minister of Canada Jean Chrétien. During the 1993 Canadian federal election, Chrétien's first as leader of the Liberal Party of Canada, the opposition Progressive Conservative Party of Canada ran an attack ad in which voice actors criticized him over images that seemed to highlight his abnormal facial expressions. The ad was interpreted as an attack on Chrétien's physical appearance and garnered widespread anger among the public, while Chrétien used the ad to make himself more sympathetic to voters. The ad had the adverse effect of increasing Chrétien's lead in the polls and the subsequent backlash clinched the election for the Liberals, which the party won in a landslide.
Carnie Wilson (born April 29, 1968) is an American singer and television host, perhaps best known as a member of the pop music group Wilson Phillips.Charles Bell
Sir Charles Bell (12 November 1774 – 28 April 1842) was a Scottish surgeon, anatomist, physiologist, neurologist, artist, and philosophical theologian. He is noted for discovering the difference between sensory nerves and motor nerves in the spinal cord. He is also noted for describing Bell's palsy.
His three older brothers included Robert Bell (1757–1816) a Writer to the Signet, John Bell (1763–1820), also a noted surgeon and writer; and the advocate George Joseph Bell (1770–1843) who became a professor of law at the University of Edinburgh and a principal clerk at the Court of Session.Cranial nerve disease
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.
It is possible for a disorder of more than one cranial nerve to occur at the same time, if a trauma occurs at a location where many cranial nerves run together, such as the jugular fossa. A brainstem lesion could also cause impaired functioning of multiple cranial nerves, but this condition would likely also be accompanied by distal motor impairment.
A neurological examination can test the functioning of individual cranial nerves, and detect specific impairments.Cranial nerves
Cranial nerves are the nerves that emerge directly from the brain (including the brainstem), in contrast to spinal nerves (which emerge from segments of the spinal cord). 10 of the cranial nerves originate in the brainstem. Cranial nerves relay information between the brain and parts of the body, primarily to and from regions of the head and neck.Spinal nerves emerge sequentially from the spinal cord with the spinal nerve closest to the head (C1) emerging in the space above the first cervical vertebra. The cranial nerves, however, emerge from the central nervous system above this level. Each cranial nerve is paired and is present on both sides. Depending on definition in humans there are twelve or thirteen cranial nerves pairs, which are assigned Roman numerals I–XII, sometimes also including cranial nerve zero. The numbering of the cranial nerves is based on the order in which they emerge from the brain, front to back (brainstem).The terminal nerves (0), olfactory nerves (I) and optic nerves (II) emerge from the cerebrum or forebrain, and the remaining ten pairs arise from the brainstem, which is the lower part of the brain.The cranial nerves are considered components of the peripheral nervous system (PNS), although on a structural level the olfactory (I), optic (II), and trigeminal (V) nerves are more accurately considered part of the central nervous system (CNS).Cyclosporiasis
Cyclosporiasis is a disease caused by infection with Cyclospora cayetanensis, a pathogenic protozoan transmitted by feces or feces-contaminated food and water. Outbreaks have been reported due to contaminated fruits and vegetables. It is not spread from person to person, but can be a hazard for travelers as a cause of diarrhea.Electroneuronography
Electroneuronography or electroneurography (ENoG) is a neurological non-invasive test used to study the facial nerve in cases of muscle weakness in one side of the face (Bell's palsy). The technique of electroneuronography was first used by Esslen and Fisch in 1979 to describe a technique that examines the integrity and conductivity of peripheral nerves. In modern use, ENoG is used to describe study of the facial nerve, while the term nerve conduction study is employed for other nerves.
It consists of a brief electrical stimulation of the nerve in one point underneath the skin, and at the same time recording the electrical activity (compound action potentials) at another point of the nerve's trajectory in the body. The response is displayed in a cathode ray tube (CRT) or through the video monitor of a computer. The stimulation as well as the recording are carried out by disc electrodes taped to the skin, and the technician may use electrically conducting gel or paste to bolster the signals being input and output. Alternatively, the recording electrodes may also be used to pick up the electrical activity of a muscle innervated by that nerve. In such instances electroneuronography is closely related to electromyography.
It is performed by an audiologist, who carries out tests to compare the two sides of the face.
The stimulation electrode is located at the stylomastoid foramen and the recording electrode is located near the nasolabial fold. The ENoG test is the only objective measure of facial nerve integrity.Facial nerve decompression
Facial nerve decompression is a type of nerve decompression surgery where abnormal compression on the facial nerve is relieved.Facial nerve paralysis
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. The most common is Bell's palsy, a disease of unknown cause that may only be diagnosed by exclusion.Facial toning
Facial toning, or facial exercise is a type of cosmetic procedure or physical therapy tool which promises to alter facial contours by means of increasing muscle tone, and facial volume by promoting muscular hypertrophy, and preventing muscle loss due to aging or facial paralysis. Facial toning and exercise is therefore in part a technique to achieve facial rejuvenation by reducing wrinkles, sagging and expression marks on the face and skin. As a physical therapy, facial toning is used for victims of stroke and forms of facial paralysis such as Bell’s palsy. Facial toning achieves this by performing facial muscle exercising. There are two types of facial toning exercises: active and passive face exercises.Facial weakness
Facial weakness is a medical sign associated with a variety of medical conditions.
Some specific conditions associated with facial weakness include:
Ramsay Hunt syndrome
Spontaneous cerebrospinal fluid leak
Myasthenia gravisHouse–Brackmann score
The House–Brackmann score is a score to grade the degree of nerve damage in a facial nerve palsy. The measurement is determined by measuring the upwards (superior) movement of the mid-portion of the top of the eyebrow, and the outwards (lateral) movement of the angle of the mouth. Each reference point scores 1 point for each 0.25 cm movement, up to a maximum of 1 cm. The scores are then added together, to give a number out of 8. The score predicts recovery in those with Bell's palsy.The score carries the name of the Dr John W. House and Dr Derald E. Brackmann, otolaryngologists in Los Angeles, California, who first described the system in 1985. It is one of a number of facial nerve scoring systems, such as Burres-Fisch, Nottingham, Sunnybrook, and Yanagihara. Of these, the Nottingham scale has been identified as possibly being easier and more reproducible. A modification of the original House–Brackmann score, called the "Facial Nerve Grading Scale 2.0" (FNGS2.0) was proposed in 2009.List of people with Bell's palsy
Well-known people who have been diagnosed with Bell's palsy include:
Roseanne Barr, American comedian and actress whose condition occurred as a child
Stevie Benton, bassist for Texas rock band Drowning Pool
Hafþór Júlíus Björnsson, Icelandic professional strongman, actor, and professional basketball player
Amy Brenneman, American actress and producer
Pierce Brosnan, Irish actor, film producer and environmentalist
Freddie Burns, England and Leicester Tigers rugby player
Scott Cairns, American poet and theological writer whose condition occurred as a child
Jean Chrétien, prime minister of Canada
George Clooney, American actor, director, producer, and screenwriter
Norm Coleman, United States Senator
Alexis Denisof, American actor
Glen Durrant, BDO World Darts Champion
Thomas C. Foley, American politician and businessman; U.S. Ambassador to Ireland
David Frum, Canadian-American pundit
Graeme Garden, British comedy writer and performer, who has written about his experiences with the condition
Allen Ginsberg, American beat poet
Tony Gonzalez, American NFL football player
Amy Goodman, American journalist and author
Jane Greer, American actress
Trenton Hassell, American basketball player for the New Jersey Nets of the NBA
Terrence Howard, American actor
Armando Iannucci, Scottish writer
Angelina Jolie, American actress and filmmaker
Anupam Kher, Indian actor
Ralph Kiner, American baseball player in the 1940s and 1950s
Ella Koon, Tahitian-born Hong Kong singer-actress
Curtis LeMay, United States Air Force general and 1968 independent vice presidential candidate
Gordon Lightfoot, Canadian singer
Martin Love, Australian cricketer
Joe Mantegna, American actor
Pete Maravich, American basketball player
Florence Mars, American civil rights activist and author
Tom McCarthy, Canadian National Hockey League player who played for the Minnesota North Stars and Boston Bruins.
Glenda McKay, British actor
Danny Meyer, American restaurateur in New York City; chief executive officer of Union Square Hospitality Group
Scarlett Moffatt, British television personality
Kim Mulkey, American basketball player and coach (Baylor University women)
Ralph Nader, American politician
Cliff Pennington, shortstop for the Oakland Athletics
Jim Ross, professional wrestling commentator for WWE and WCW
Rick Savage, bass guitarist for the British rock band Def Leppard
Tom Seaver, Hall of Fame Major League pitcher
Bernadette Sembrano, Filipino newscaster, host of the medical program Salamat Dok! and anchor of TV Patrol Weekend
Ayrton Senna, Brazilian Formula One racecar driver
Rahul Sharma, Indian cricketer
Jamey Sheridan, American actor whose condition was written into the show Law and Order: Criminal Intent
Sarah Smart, English actress
Mike South, American pornographic director
Bruce Sutter, American Major League Baseball pitcher
Bart Tommelein, Belgian politician
Kevin Tsai, Taiwanese writer and TV host
Colin Turkington, British touring car racing driver
Evan Turner, American basketball player
Chris Walker, British superbike racer
Wesley Walker, American football player was unable to blink his left eye due to Bell's palsy in 1982, but played football anyway
Andrew Lloyd Webber, British composer
Joseph C. Wilson, American diplomat
Nancy Zieman, American television host of the show Sewing with NancyMatt Weibring
Matthew Kirk Weibring (born December 4, 1979) is an American professional golfer. He is the son of D. A. Weibring.Weibring turned professional in 2002, and played on the second-tier Nationwide Tour in 2003 and 2005–08. He played on the PGA Tour in 2009–10 after graduating in 24th place from the 2008 Nationwide Tour. In 2011 he returned to the Nationwide Tour. Weibring's best result on the PGA Tour is T8 at the 2009 Verizon Heritage. He also played on the Canadian Tour in 2003.
Weibring has a history of injuries, include hip and knee surgery. He has Bell's palsy, a condition his father overcame during his career, and cannot blink his right eye.Nancy Zieman
Nancy L. Zieman (née Luedtke; June 21, 1953 – November 14, 2017) was an American author and designer widely known as the host of the television show Sewing with Nancy.Palsy
Palsy is a medical term which refers to various types of paralysis, often accompanied by weakness and the loss of feeling and uncontrolled body movements such as shaking. The word originates from the Anglo-Norman paralisie, parleisie et al., from the accusative form of Latin paralysis, from Ancient Greek παράλυσις (parálusis), from παραλύειν (paralúein, “to disable on one side”), from παρά (pará, “beside”) + λύειν (lúein, “loosen”). The word is longstanding in the English language, having appeared in the play Grim the Collier of Croydon, reported to have been written as early as 1599:
Rob. I'll have thee come, I say. Why tremblest thou?Grim. No sir, not I; 'tis a palsy I have still.
In some editions, the Bible passage of Luke 5:18 is translated to refer to "a man which was taken with a palsy". More modern editions simply refer to a man who is paralysed. Although the term has historically been associated with paralysis generally, "is now almost always used in connection to the word “cerebral”—meaning the brain".Specific kinds of palsy include:
Bell's palsy, partial facial paralysis
Bulbar palsy, impairment of cranial nerves
Cerebral palsy, a neural disorder caused by intracranial lesions
Conjugate gaze palsy, a disorder affecting the ability to move the eyes
Erb's palsy, also known as brachial palsy, involving paralysis of an arm
Spinal muscular atrophy, also known as wasting palsy
Progressive supranuclear palsy, a degenerative disease
Squatter's palsy, a common name for bilateral peroneal nerve palsy that may be triggered by sustained squatting
Third nerve palsy, involving cranial nerve IIIRahul Sharma (Indian cricketer)
Rahul Sharma (born 20 July 1987 in New Delhi, Punjab) is an Indian cricketer. He is primarily a right-handed legbreak and googly bowler. He has been a member of the Punjab cricket team since 2006. He came into the limelight due to his impressive bowling performances in IPL 2011 for Pune Warriors.Roberto Pérez
Roberto Pérez (born December 23, 1988) is a Puerto Rican professional baseball catcher for the Cleveland Indians of Major League Baseball (MLB).Sewing with Nancy
Sewing with Nancy was an American television show about sewing, hosted by Nancy Zieman. It made its debut on the now-defunct Satellite Program Network (SPN, later Tempo Television) in September 1982. On September 1, 1982, PBS began airing the series, which was distributed by NETA. As of 2011, the show aired on 89% of Public Television stations in the United States. It was the longest-running sewing series in the history of North American television.Sewing with Nancy was co-produced by Wisconsin Public Television at Vilas Hall on the University of Wisconsin campus in Madison. Zieman had Bell's palsy, a one-sided facial nerve paralysis, and talked about the condition on an episode in 2011. On September 5, 2017, Zieman announced her retirement due to cancer; she died just over two months later, the day after the final episode was broadcast. Older episodes continue to be broadcast on PBS under the name The Best of Sewing with Nancy.Stylomastoid foramen
Between the styloid and mastoid processes of the temporal bone is the stylomastoid foramen
It is the termination of the facial canal, and transmits the facial nerve and stylomastoid artery.