Bell’s palsy: Acute idiopathic unilateral paralysis of the facial nerve.

The prototypic case is a lower motor neuron lesion of the facial nerve that presents after a viral prodrome. The patient wakes up in morning and notices in the mirror signs of facial nerve paralysis. Aetiology is most commonly vascular, inflammatory or viral. Risk factors include pregnancy, obesity, hypertension and diabetes

  • Drooping of eyelid or an inability to completely close the eye
  • Drooping of the corner of the mouth
  • Unable to raise an eyebrow or wrinkle the forehead
    • Dry eye with epiphora (excessive tearing)
    • Ipsilateral loss of taste sensation
    • Hyperacusis
    Differential diagnosis
    • Central Lesion of the facial nucleus of the brain stem, UMNL
    • Ramsy Hunt syndrome (Herpes Zoster oticus), painful rash in ear
    • Miller Fisher variant GBS
    • Note: Can present as a polyneuritis involving trigeminal, glossopharyngeal, 2nd cervical or vagal nerve.
    Course and treatment
    • Usually self-limiting and resolves after 12 weeks. Up to 30% have some residual symptoms.
    • Steroids help in severe cases (early complete paralysis) improves recovery time.
    • The House-Brackmann grading scale can be used for assessing severity and progression.
    • Most important supportive treatment is eye protection!

    History of Bell’s Palsy

    1020 – Avicenna (Ibn Sinh) (980-1037) –  described spastic, atonic and convulsive types of facial palsy in ‘Al Qanun Fi Al-Tibb’ (The Canon of Medicine) translated into Latin in the 12th century and then into English (Gruner 1930)

    1797 – Nikolaus Friedreich (1825-1882) in ‘De paralysis musculorum faciei rheumatica.’ provides a detailed description of idiopathic peripheral facial nerve paralysis demonstrating careful clinical observations;  deductive reasoning about the nervous system; useful speculation about pathophysiology and practical attempts at treatment. [Reference]

    1821, Sir Charles Bell briefly mentioned a man whose facial nerve was injured by a:

    suppuration which took place anterior to the ear and through which the nerve passed in its course to the face…cases of this partial paralysis must be familiar to every medical observer. It is frequent for young people to have what is vulgarly called a blight; by which is meant, a slight palsy of the muscles on one side of the face, and which the physician knows is not formidable

    Bell C. 1821: 21, 25

    In 1827, Bell’s classic description was outlined in a case of paralysis of the face on his patient Daniel Stadler.

    Associated Persons
    • Avicenna [Ibn Sīnā] (980-1037)
    • François Magendie (1783-1855)
    • Nikolaus Friedreich (1825-1882)
    • Sir Charles Bell (1774–1842)

    Alternative names
    • Idiopathic peripheral facial paralysis


    It is commonly commented that Bell himself had a right peripheral facial paralysis, however this is erroneous. Bell refers not to himself, but to the physician Professor Roux of Paris who suffered facial paralysis in 1821 [Bell C. 1828 case XVII pp68-70]



    the names behind the name

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