Long-term sequelae treatment of peripheral facial paralysis with botulinum toxin type A: Repartition and kinetics of doses used

Botulinum toxin A treatment in facial palsy synkinesis: a systematic review and meta-analysis

BACKGROUND

Synkinesis is defined as involuntary movements accompanying by voluntary movements and can occur during the aftermath of peripheral facial palsy, causing functional, aesthetic and psychological problems in the patient. Botulinum toxin A (BTX-A) is frequently used as a safe and effective treatment; however, there is no standardized guideline for the use of BTX-A in synkinesis. The purpose of this article is to review and summarize studies about the BTX-A treatment of synkinesis in patients with a history of peripheral facial palsy; including given dosages, injection sites and time intervals between injections.

MATERIALS AND METHODS

A multi-database systematic literature search was performed in October 2020 using the following databases: Pubmed, Embase, Medline, and The Cochrane Library. Two authors rated the methodological quality of the included studies independently using the 'Newcastle-Ottawa Quality Assessment Scale' for non-randomised studies' (NOS).

RESULTS

Four-thousand-five-hundred-and-nineteen articles were found of which 34 studies met the inclusion criteria, in total comprising 1314 patients. Most studies were assessed to be of 'fair' to 'good' methodological quality. The Cohen's kappa (between author FJ and AS) was 0.78. Thirty-one studies investigated the reported dosage injected, 17 studies reported injection location and 17 studies investigated time intervals. A meta-analysis was performed for three studies comprising 106 patients, on the effects of BTX-A treatment on the Synkinesis Assessment Questionnaire (SAQ) scores. The mean difference was 11.599 (range 9.422-13.766), p < 0.01. However, due to inconsistent reporting of data of the included studies, no relationship with the dosage and location could be assessed.

CONCLUSIONS

Many treatment strategies for synkinesis exist, consisting of varying BTX-A brands, dosages, time intervals and different injection locations. Moreover, the individual complaints are very specific, which complicates creating a standardized chemodenervation treatment protocol. The BTX-A treatment of long-term synkinesis is very individual and further studies should focus on a patient-tailored treatment instead of trying to standardize treatment.

Cost of peripheral facial palsy treatment with Botulinum Toxin type A

INTRODUCTION

Facial palsy (FP) is one of the most common neuropathies. Overall, 15%-30% of patients develop chronic sequelae. Several studies support the use of botulinum toxin A (BoNT-A) in the treatment of FP sequelae. No studies have analyzed the cost of treating FP with BoNT-A.

METHODS

A retrospective review of data from all clinical records of consultations and procedures that took place at the FP Treatment Unit clinic throughout 2017. Type of BoNT-A used, total dose used, unilateral or bilateral injection, date of consultation, and gender were collected. The price of expendable materials, BoNT-A, and the 2017 salary scale was obtained to establish costs.

RESULTS

During 2017, 605 clinical procedures were conducted in 240 patients. The mean number of procedures was 2.5 (0.80). The average time between procedures was 124(28.72) days. The total annual cost was 34.155,10€. The average annual cost of BoNT-A for each procedure was 39,93€, and the total annual cost of BoNT-A was 24.160,58€. On average, more units of IncotoxA were injected. This difference is not reflected in the final cost of each BoNT-A. For patients who achieved treatment stability, the average annual cost per patient was 106,6€ (OnatoxA) and 100,6€ (IncotoxA).

CONCLUSION

In our unit, treatment with BoNT-A in FP sequelae had an average annual cost of 124,31€ per patient, requiring a visit to the hospital to receive treatment every 124 days. Given the functional and quality of life improvements, we should consider that it is a beneficial treatment at an acceptable cost.

[Synkinesis in facial palsy: What do we know about the physiopathology?]

INTRODUCTION

Synkinesis is a disabling sequelae of facial palsy, which worsens facial asymmetry and diminishes the patients' quality of life. Their physiopathology is partially known, but cannot explain all the synkinesis.

MATERIAL AND METHODS

We report a literature review of the state of the art concerning the knowledge on synkinesis physiopathology, as well as their management.

RESULTS

It is accepted that the physiopathological mechanism of synkinesis is mixed. The phenomena of cerebral plasticity, aberrant nerve regrowth, hyperexcitability of the facial nerve nucleus and ephaptic nerve transmission, have been observed. We propose a new physiopathological hypothesis: synkinesis could be the consequence of latent circuits activation, preexisting in the healthy subject. We could propose three potential latent circuits: physiological synergistic contractions, adjacent motor units recruitment, and reactivation of remote latent circuits for function compensation. The treatment options are multiple, dominated by chemodenervation, whose effectiveness is undeniable. Rehabilitation has also proven its effectiveness, particularly with feedback techniques. Finally, surgery helps with these options. However, the indications of the different treatments remain to be codified.

CONCLUSION

The validation of our physiopathological hypothesis would allow a better understanding and a better screening of synkinesis, in order to propose a more adapted treatment.

[Satisfaction survey of patients with sequels of peripheral facial palsy treated with botulinum toxin A]

INTRODUCTION

Treatment of peripheral facial palsy with botulinum toxin A is safe and effective. Although its beneficial impact on patients' quality of life is known, to date, there have been no studies specifically analysing patients' subjective perceptions.

PATIENTS AND METHOD

We performed a prospective study in a random sample of patients with sequels of peripheral facial palsy treated with botulinum toxin in the Physical Medicine and Rehabilitation Service of our hospital. We created a simple questionnaire to assess both patient satisfaction and subjective perception of improvement after botulinum toxin treatment.

RESULTS

After infiltration, 95% of the patients felt good or very good. More than 80% noted improvement in the sensation of tightness in the cheek and neck. Around 75% of patients perceived an improvement in the range of voluntary movement and approximately 80% reported improvement in synkinesis. Almost all the patients would repeat the treatment, if proposed, and 100% would recommend botulinum toxin infiltration to other patients with facial palsy.

CONCLUSIONS

Patients treated with botulinum toxin experience substantial subjective improvement in the sequels of peripheral facial palsy, both in repose and in the control of synkinesis. Satisfaction was higher than 8/10 in 99% of patients in this study.

Treatment Patterns and Outcomes in Botulinum Therapy for Patients With Facial Synkinesis

Importance

In the last decade, there has been a significant increase in the number of practitioners administering botulinum toxin for facial synkinesis. However, there are few resources available to guide treatment patterns, and little is known about how these patterns are associated with functional outcomes and quality of life.

Objective

To evaluate botulinum treatment patterns, including the dosing and frequency of muscle targeting, for treatment of facial synkinesis and to quantify patient outcomes.

Design, Setting, and Participants

This prospective cohort study of 99 patients treated for facial synkinesis was conducted from January 2016 through December 2018 at the Vanderbilt Bill Wilkerson Center in Nashville, Tennessee, a tertiary referral center.

Intervention

Onabotulinum toxin A treatment of facial synkinesis.

Main Outcomes and Measures

Patient-reported outcomes on the Synkinesis Assessment Questionnaire and botulinum treatment patterns, including the dosages and frequency of injection for each facial muscle, were compared at the initiation of treatment and at the end of recorded treatment.

Results

In total, 99 patients (80 female patients [81%]) underwent botulinum injections for treatment of facial synkinesis. The median (interquartile range) age was 54.0 (43.5-61.5) years, and the median (interquartile range) follow-up was 27.1 (8.9-59.7) months. Most patients underwent injections after receiving a diagnosis of Bell palsy (41 patients, 41%) or after resection of vestibular schwannoma (36 patients [36%]). The patients received a total of 441 treatment injections, and 369 pretreatment and posttreatment Synkinesis Assessment Questionnaire scores were analyzed. The mean botulinum dose was 2 to 3 U for each facial muscle and 9 to 10 U for the platysma muscle. The dose increased over time for the majority of all muscles, with steady state achieved after a median of 3 treatments (interquartile range, 2-3). Linear regression analysis for cluster data of the mean total questionnaire score difference was -14.2 (95% CI, -17.0 to -11.5; P < .001). There was a significant association of postinjection questionnaire score with younger patients, female sex, total dose, and synkinesis severity. Oculo-oral synkinesis may respond more to treatment compared with oro-ocular synkinesis.

Conclusion and Relevance

Patients with facial synkinesis responded significantly to botulinum treatment. Treatment began with 6 core facial muscles that were injected during most treatment sessions, and dosages increased after the first injection until steady state was achieved. Those with a greater degree of morbidity, younger patients, and females showed significant improvement, and the larger the dose administered, the greater the response. Oculo-oral synkinesis may be more responsive than oro-ocular synkinesis.

Level of Evidence

3.

Toxin-induced hormesis may restrain aging

Mild environmental stress might have beneficial effects in aging by activating maintenance and repair processes in cells and organs. These beneficial stress effects fit to the concept of hormesis. Prominent stressors acting in a hormetic way are physical exercises, fasting, cold and heat. This review will introduce some toxins, which have been found to induce hormetic responses in animal models of aging research. To highlight the molecular signature of these hormetic effects we will depict signaling pathways affected by low doses of toxins on cellular and organismic level. As prominent examples for signaling pathways involved in both aging processes as well as toxin responses, PI3K/Akt/mTOR- and AMPK-signal transduction will be described in more detail. Due to the striking overlap of signaling pathways mediating toxin induced responses and aging processes we propose considering the ability of low doses of toxins to slow down the rate of aging.