The natural history of Bell's palsy.

The purpose of this investigation was to explain the spontaneous course of idiopathic facial palsy without treatment of any kind. The investigation included 1011 patients seen over a fifteen-year period. The patients were checked at short intervals until remission occurred, and these checks were discontinued only when normal function was restored or after a period of one year. For 85 percent of patients the first signs of remission were observed within three weeks after the outbreak; for the last 15 percent remission occurred three to six months later. Seventy-one percent recovered normal mimical function of the face, 13 percent had insignificant sequelae, and the last 16 percent had permanently diminished function with contracture and associated movements.