Abstract
Unilateral peripheral facial nerve palsy jeopardizes quality of life, rendering psychological consequences such as low self-esteem, social isolation, anxiety, and depression. Among therapeutical approaches, use of Botulinum toxin type A (BoNT-A) on the nonparalyzed side has shown promising results and improvement of quality of life. Nevertheless, the correct technique is paramount, since over-injection of the muscles can result in lack of function, leading to a “paralyzed” appearance, and even worse, functional incompetence, which may cause greater distress to patients. Therefore, the objective of this article is to provide a practical guideline for botulinum toxin use in facial palsy. To this aim, adequate patient assessment, BoNT-A choice, injection plan and dosage, and injection techniques are covered.
Highlights
Regardless of its etiology, idiopathic (Bell’s Palsy) or secondary facial nerve palsy, due to multiple etiologies such as Ramsey Hunt syndrome, infection, vascular, tumor resection and base of skull injuries, among others, manifests a unilateral peripheral facial nerve palsy which may lead to involuntary static and dynamic alterations of facial expression due to aberrant regeneration of fibers in the neural repair process in as many as 55.5% of patients with longstanding facial weakness [1,2,3,4,5]
The treatment options for facial nerve palsy usually aim to activate the mimic muscles on the affected side, or improve symmetry on both sides and can range from conservative to more invasive approaches, and the choice depends upon the etiology and the pathogenesis of the condition [1,6]
Botulinum toxin type A (BoNT-A) injection in the nonparalyzed side has been used since 1987 for the treatment of asymmetries caused by facial paralysis and has shown promising results and improvement of quality of life; only a small minority of injectors feel able to treat this condition, which requires a complex approach and a detailed knowledge of facial functional anatomy
Summary
Regardless of its etiology, idiopathic (Bell’s Palsy) or secondary facial nerve palsy, due to multiple etiologies such as Ramsey Hunt syndrome, infection, vascular, tumor resection and base of skull injuries, among others, manifests a unilateral peripheral facial nerve palsy which may lead to involuntary static and dynamic alterations of facial expression due to aberrant regeneration of fibers in the neural repair process in as many as 55.5% of patients with longstanding facial weakness [1,2,3,4,5]. The objective of this article is to provide a practical guideline for botulinum toxin use in facial palsy To this aim we will review patient assessment based on functional anatomy to assist in an individualized approach. Individuals with flaccid paralysis (prosopoplegia) may present absence of wrinkles on the forehead on the paralyzed side and important functional deficits, such as lagophthalmos with potential for corneal ulceration and blindness, as well as oral incompetence, poor articulation, lip and buccal mucosa biting These individuals develop brow and facial ptosis, severe facial atrophy, an effaced nasolabial fold, and absent animation, affecting mainly the smile mechanism, on the affected side [12,13]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
