Botulinum toxin type A in the treatment of synkinesis: a clinical case report and literature review

Synkinesis that develop in the long-term period of damage to the facial nerve significantly reduce the quality of life of patients. However, to date there is no single algorithm for the treatment of this category of patients. The purpose of the article was to describe the principle of treatment of synkinesis that developed after damage to the facial nerve, as well as to summarize the available literature data on the pathophysiological features and principles of botulinum therapy for this category of patients. We present a clinical case of a patient who, 10 months after removal of an acoustic neuroma on the right, developed motor synkinesis. The patient underwent 5 courses of botulinum toxin type A (BTA) injections with a positive effect. The article analyzes in detail the pathophysiological mechanisms of the development of synkinesis. Also presented data from studies since 2015 that assessed the intervals between injections, the total dosage of the drug and the dosage of one injection for patients with synkinesis. Conclusion: long-term treatment of synkinesis with BTA is individual, requires video recording of clinical, written (graphic) recording of injection points and assessment according to the Sunnybrook Facial Grading Scale and Facial Disability Index before and before the next injection session. Future research should focus on personalization rather than standardization of treatments.