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
Additional symptoms (related to facial nerve function)
- Dry eye with epiphora (excessive tearing)
- Ipsilateral loss of taste sensation
- 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!
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’ [Bell C. 1821 p21] and that ‘…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 p25]
- Avicenna [Ibn Sīnā] (980-1037)
- François Magendie (1783-1855)
- Nikolaus Friedreich (1825-1882)
- Sir Charles Bell (1774–1842)
- 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]
- Afnan SM. AVICENNA [Ibn Sina]: His life (980-1037) and Work. 1958
- Gruner OC. A Treatise on the Canon of Medicine of Avicenna; with translation of the First Book. London: Luzac 1930
- Friedreich NA. De paralysis musculorum faciei rheumatica. J. der Erfindungen (Gotha), Vol. 8, No. XXV. In: Annals of Medicine (Edinburgh) 1800,5, 214-226.
- Bird TD. Nicolaus A. Friedreich’s description of peripheral facial nerve paralysis in 1798. J Neurol Neurosurg Psychiatry. 1979;42:56-58.
- Magendie F. Expériences sur les fonctions des racines des nerfs rachidiens . J. Physiol. Exp. Pathol. 1822;2 276–279
- Magendie F. Mémoire sur quelques découvertes récentes relatives aux fonctions du système nerveux. 1823
- Bell C. Appendix to the papers on the nerves. London: Longman 1827:68-72
- Goldman L, Schechter CG. Art in Medicine. Peripheral facial palsy throughout the ages.. N Y State J Med. 1967 May 15;67(10):1331-4. [PMID 5342413]
- Wilkins RH, Brody IA. Bell’s Palsy and Bell’s Phenomenon. Arch Neurol. 1969;21(6):661-662.