Bell's paralysis

Peripheral, usually unilateral, idiopathic paralysis of facial muscles. Less than 1% of cases are bilateral. Characterized by weakness of the entire half of the face, pain and swelling behind the ears and pain and stiffness of the neck, followed by paralysis. The patient cannot control salivation or lacrimation, and in severe cases cannot close the eye on the affected side. Facial expression is distorted. Sudden onset.

The incidence of Bell's palsy is estimated to be 20 to 30 per 100,000, but appears to increase with age. There is an equal male to female ration and a 3.3 times greater incidence in pregnant females. Patients with diabetes have 4–5 times more risk of developing the disease.
Sometimes following exposure to cold or draft; most cases benign without apparent reason. The cause is unknown but is presumed to involve swelling of the seventh (facial) nerve due to immune or viral disease; familial cases reported.

See also Mona Lisa syndrome, a facial muscle contracture that develops after Bell’s palsy under Mona Lisa – Lisa di Antonio Maria Gherardini, wife of Francesco del Giocondo. Also known as La Gioconda.

• Nicolaus Anton Friedreich:
  De paralysi musculorum faciei rheumatici. Wirceburgi, 1797.
• C. Bell:
  On the nerves; giving an account of some experiments on their structure and functions, which lead to a new arrangement of the system.
  Philosophical Transactions of the Royal Society of London, 1821; 111: 398-424. On the nerves of the face; being a second paper on that subject.
  Reprinted in Medical Classics 1936, 1: 155-169.
• Robert C. van de Graaf, Jean-Philippe A. Nicolai:
  Bell's palsy before Bell: Cornelis Stalpart van der Wiel's observation of Bell's palsy in 1683.
  Otologt & Naurotology, November 2005, 26 (6): 1235-1238.
  The authors are affiliated with the Department of Otorhinolaryngology, Head and Neck Surgery, University Medical Center Groningen, The Netherlands.
  
  "Bell's palsy is named after Sir Charles Bell (1774-1842), who has long been considered to be the first to describe idiopathic facial paralysis in the early 19th century. However, it was discovered that Nicolaus Anton Friedreich (1761-1836) and James Douglas (1675-1742) preceded him in the 18th century. Recently, an even earlier account of Bell's palsy was found, as observed by Cornelis Stalpart van der Wiel (1620-1702) from The Hague, The Netherlands in 1683. Because our current knowledge of the history of Bell's palsy before Bell is limited to a few documents, it is interesting to discuss Stalpart van der Wiel's description and determine its additional value for the history of Bell's palsy. It is concluded that Cornelis Stalpart van der Wiel was the first to record Bell's palsy in 1683. His manuscript provides clues for future historical research."
  
  Stalpart van der Wiel in 1683 gave a detailed report of Bell's palsy as “a wryness or one-sided spasm of the mouth.” Douglas described it in 1704, Friedreich in 1797.