Sections View Full Chapter Figures Tables Videos Annotate Full Chapter Figures Tables Videos Supplementary Content ++ Facial palsyPeripheral facial paralysis ++ 351.0 Bell’s palsy ++ G51.0 Bell’s palsy, facial palsy +++ Description ++ Paralysis or weakness of muscles on one side of faceSudden onset, often overnightDamage to the 7th cranial (facial) nerve that controls muscles on one side of the face, causing that side of face to droopNerve damage may affect sense of taste, production of tears and saliva +++ Essentials ++ Lower motor neuron (LMN) disease Diagnosis usually made by history and clinical examination +++ General Considerations ++ Afflicts approximately 40,000 Americans each year +++ Demographics ++ Equally likely in men and women Can present at any age, but less common before age 15 years or after age 60More prevalent in people with diabetes or upper respiratory ailments, such as flu or cold More likely in pregnant women +++ Signs and Symptoms ++ Sudden weakness or paralysis on one side of face that causes it to droop (main symptom)Difficulty closing eye on affected sideDroolingDry mouthEye problems, such as excessive tearing or dry eyeLoss of ability to tastePain in or behind earFacial numbness on affected side Increased sensitivity to soundHeadacheFacial twitchInability to smile or make facial expressions +++ Functional Implications ++ Dry eyesEatingHearingPsychological impact +++ Possible Contributing Causes ++ The nerve that controls muscles on one side of the face is damaged by inflammation in most casesRoot cause of Bell's palsy is not clear Most cases thought to be caused by the herpes virus that causes chickenpox and shingles, or Epstein-Barr virus that causes mononucleosis +++ Differential Diagnosis ++ StrokeHIV infectionHerpes simplex virusInfectionsLyme diseaseMiddle ear infectionMeningitisDiabetes mellitusSarcoidosisBrucellosisTumorsRamsay Hunt syndrome +++ Laboratory Tests ++ Blood tests +++ Imaging ++ MRI of the head to rule out brain tumorCT scan of the head to rule out brain tumor +++ Diagnostic Procedures ++ History and physical and neurological exam to check facial nerve functionIf cause of symptoms is not clear, other tests are needed, such as Nerve conduction test for facial nerveElectromyography (EMG) for facial nerve ++ Facial muscle weakness or total paralysis (e.g., unable to frown) due to swollen, inflamed, or compressed facial nerveDrooping of eyelid and corner of mouth on the affected side due to muscle weakness or paralysis ++ OphthalmologistsEar, Nose & Throat surgeonsPlastic surgeonsPsychologists ++ Impaired facial expression due to paralysisProblems eating (food stuck in month or falling ... Your Access profile is currently affiliated with '[InstitutionA]' and is in the process of switching affiliations to '[InstitutionB]'. Please click ‘Continue’ to continue the affiliation switch, otherwise click ‘Cancel’ to cancel signing in. Get Free Access Through Your Institution Learn how to see if your library subscribes to McGraw Hill Medical products. Subscribe: Institutional or Individual Sign In Username Error: Please enter User Name Password Error: Please enter Password Forgot Password? Forgot Username? Sign in via OpenAthens Sign in via Shibboleth You already have access! Please proceed to your institution's subscription. Create a free a profile for additional features.