Is It Always Necessary to Apply Botulinum Toxin into the Lower Facial Muscles in Hemifacial Spasm? A Randomized, Single-Blind, Crossover Trial

Abstract

Background: Botulinum toxin (BTX) injections are accepted as safe and efficacious in the treatment of hemifacial spasm (HFS), but it is still debated whether BTX treatment of lower facial muscles should be performed or not. Objective: The study aims to evaluate the necessity of BTX administration into lower facial muscles in patients with HFS. Methods: A randomized, single-blind, crossover, clinical trial was conducted. Twenty-three HFS patients were randomly allocated to two different application methods. The patients were administered BTX type A into both the orbicularis oculi and perioral muscles in the first method and BTX type A into the orbicularis oculi but placebo into the perioral muscles in the second method. Subjects were crossed over to the alternate method when they needed BTX injection with a minimum of 3 months’ duration. All the patients underwent both methods with no change in the total dose of BTX. Results: All the patients benefited from BTX treatment regardless of the methods. However, in the patients with severe lower facial muscle involvement, the application of BTX into both orbicularis oculi and lower facial muscles led to better results. Conclusion: Our data suggest that BTX application to lower facial muscles might not be necessary in patients with mild lower facial involvement.

Botulinumtoxin – Therapie des Spasmus hemifacialis: Ein Update

“…Meist wird v. a. der M. orbicularis oculi (zumeist der orbitale Anteil) behandelt, die untere Gesichtshälfte wird seltener mitbehandelt [34]. In Einzelfällen erfolgt eine Injektion auch in den M. frontalis, häufig auch intra-oder subkutan im Bereich des Platysma und unilateral in den M. mentalis.…”

Botulinum Toxin for the Treatment of Hemifacial Spasm: An Update on Clinical Studies

“…In a subgroup of HFS patients, characterized by mild symptomatology, the treatment of orbicularis oculi seemed to be able to control muscle contractions, even in the lower part of the face [4]. This might be due to either the lowering of a triggering spasm from the upper muscles or the spread of the botulinum toxin [48]. In the case of more severe spasms involving the lower facial muscles, a broader treatment targeting the lower facial muscles is recommended [48].…”

“…This might be due to either the lowering of a triggering spasm from the upper muscles or the spread of the botulinum toxin [48]. In the case of more severe spasms involving the lower facial muscles, a broader treatment targeting the lower facial muscles is recommended [48].…”

Therapie des Spasmus hemifacialis mit Botulinumtoxin

“…Meist wird v. a. der M. orbicularis oculi (zumeist der orbitale Anteil) behandelt; die untere Gesichtshälfte wird seltener mitbehandelt [31]. In Einzelfällen erfolgt eine Injektion auch in den M. frontalis, häufig auch intra-oder subkutan im Bereich des Platysma und unilateral in den M. mentalis.…”