Botulinum toxin treatment for facial palsy: A systematic review

Summary Background Facial palsy may be complicated by ipsilateral synkinesis or contralateral hyperkinesis. Botulinum toxin is increasingly used in its management, however the optimum dose, treatment interval, adjunct therapy and performance as compared with alternative treatments has not been well established. This study aimed to systematically review the evidence for the use of Botulinum toxin in facial palsy. Method The Cochrane central register of controlled trials (CENTRAL), MEDLINE(R) (1946 to September 2015), Embase Classic + Embase (1947 to September 2015) were searched for randomised studies using Botulinum toxin in facial palsy. Results Forty-seven studies were identified, and three included. Their physical and patient-reported outcomes are described, and observations and cautions discussed. Discussion Facial asymmetry has a strong correlation to subjective domains such as impairment in social interaction, and perception of self-image and appearance. Botulinum toxin injections represent a minimally invasive technique, helpful in restoring facial symmetry at rest and during movement in chronic, and potentially acute, facial palsy. Botulinum toxin in combination with physical therapy may be particularly helpful. Currently there is a paucity of data; areas for further research are suggested. A strong body of evidence may allow Botulinum toxin treatment to be nationally standardised and recommended in the management of facial palsy.