Botulinum toxin for Frey's syndrome: a closer look at different treatment responses

The preventive effect of decellularized pericardial patch against Frey's syndrome following the superficial parotidectomy

PURPOSE

This study aimed to investigate the feasibility of adopting the ThormalGEN surgical patch (a porcine decellularized pericardial patch) in the superficial parotidectomy to prevent postoperative Frey's syndrome in patients with benign parotid tumor.

MATERIALS AND METHODS

A total of 59 patients with benign parotid tumor undergoing superficial parotidectomy between April 2016 and January 2017 were enrolled, and divided into the ThormalGEN group (n = 37) and the control group (n = 22) based on their willingness to have the ThormalGEN surgical patch used in the superficial parotidectomy. At 6 months postoperation, the incidences of postoperative complications and Frey's syndrome were assessed by subjective assessment (patient self-assessment) and objective assessment (starch-iodine test), respectively. The risk factor of Frey's syndrome was analyzed by the multivariate logistic regression model.

RESULTS

The starch-iodine test, for objective assessment, showed that the ThormalGEN group had a significantly lower incidence of Frey's syndrome than the control group (8.11% vs. 40.91%, p = 006). However, in the patient self-assessment, there was no significant difference in the incidence of Frey's syndrome between groups (8.11% [3/37] vs. 13.64% [3/22], p = 0.4968). The incidences of postoperative complications were not significantly different between group (all p > 0.05). Two patients (5.41%) in the ThormalGEN group had salivary fistula. Multivariate logistic regression analysis showed that the ThormalGEN group had a significantly lower risk of Frey's syndrome than the control group (odds ratio = 0.11, 95% confidence interval = 0.02-0.51, p < 0.01).

CONCLUSION

These results suggest that the ThormalGEN surgical patch can effectively reduce the incidence of Frey's syndrome following superficial parotidectomy in patients with benign parotid tumor, and that this patch has a good safety and biocompatibility profile.

Temporoparietal frey syndrome: An uncommon variant of a common syndrome

OBJECTIVES/HYPOTHESIS

To describe a previously unreported variant of Frey syndrome. Gustatory sweating is a common complication of parotidectomy and typically directly overlies the surgical site or parotid bed. In some instances, the sweating may occur beyond the parotid bed or involve tissue that was undisturbed during the procedure.

STUDY DESIGN

Retrospective case series.

METHODS

All cases of temporoparietal Frey syndrome in a single surgeon's experience were reviewed.

RESULTS

Seven patients were found to have temporoparietal Frey syndrome. Three patients had concomitant first bite syndrome. Three patients had some form of reconstruction at time of surgery. The mean time to onset of symptoms was 11.5 months, with a range of 7 to 21 months. Four patients did not require any treatment for their symptoms, but two patients required intradermal Botox injections for symptomatic relief.

DISCUSSION

This study describes a previously unreported variant of Frey syndrome with symptoms occurring distal to the parotid gland. This likely develops either by regeneration of severed postganglionic fibers into sympathetic targets distally along the course of the auriculotemporal nerve or by regeneration into fibers of the sympathetic plexus traveling along the superficial temporal artery.

LEVEL OF EVIDENCE

Laryngoscope, 129:2071-2075, 2019.

The therapeutic usage of botulinum toxin (Botox) in non-cosmetic head and neck conditions - An evidence based review

Botulinum toxin (Botox) is an exotoxin produced from Clostridium botulinum. It blocks the release of acetylcholine from the cholinergic nerve end plates resulting in inactivity of the muscles or glands innervated. The efficacy of Botox in facial aesthetics is well established; however, recent literature has highlighted its utilization in multiple non-cosmetic medical and surgical conditions. The present article reviews the current evidence pertaining to Botox use in the non-cosmetic head and neck conditions. A literature search was conducted using MEDLINE, EMBASE, ISI Web of Science and the Cochrane databases limited to English Language articles published from January 1980 to December 2014. The findings showed that there is level 1 evidence supporting the efficacy of Botox in the treatment of laryngeal dystonia, headache, cervical dystonia, masticatory myalgia, sialorrhoea, temporomandibular joint disorders, bruxism, blepharospasm, hemifacial spasm and rhinitis. For chronic neck pain there is level 1 evidence to show that Botox is ineffective. Level 2 evidence exists for vocal tics and trigeminal. For stuttering, facial nerve paresis, Frey's syndrome and oromandibular dystonia the evidence is level 4. Thus, there is compelling evidence in the published literature to demonstrate the beneficial role of Botox in a wide range of non-cosmetic conditions pertaining to the head and neck (mainly level 1 evidence). With more and more research, the range of clinical applications and number of individuals getting Botox will doubtlessly increase. Botox appears to justify its title as 'the poison that heals'.

Efficacy and safety of botulinum toxin type A for treatment of Frey's syndrome: evidence from 22 published articles

Frey’s syndrome (FS) is an unavoidable sequela following the surgery of the parotid gland. Although several treatment methods are available, their efficacy is short term or accompanied by unacceptable complications. In the past two decades, botulinum toxin type A (BTXA) has been widely used to treat FS. Although several systematic reviews have been reported recently, they were conflicting and with obvious deficiencies. Thus, we performed an objectively systematic review to determine whether BTXA is an effective and safe treatment for FS. A literature retrieval covering PubMed, Web of Science, Ovid, Embase and Cochrane library was performed on 16 January, 2015. Proportion meta-analysis and corresponding 95% confidence interval (CI) were performed to evaluate the efficacy and safety of BXTA in treatment of FS. A total of 499 records were retrieved and 22 articles with 23 studies were included after scrutiny by two independent authors. Statistical analyses regarding the effective rate, incidence of complications were used to estimate the efficacy and safety of BTXA. Our results suggested that the effective rate of BTXA for treatment of FS is 98.5% (95% CI = 0.971–0.994) and the incidence of complication is 3.6% (95% CI = 0.017–0.061). In conclusion, our study supports that BTXA produces meaningful benefits on the treatment of patients with FS. However, owing to lack of strong evidence, future studies with well-designed inclusion criteria and multicenter randomized controlled trials are needed to give more credible evidence, if possible.

Temporomandibular Myofacial Pain Treated with Botulinum Toxin Injection

This article reviews the diagnoses and treatment of temporomandibular disorders (TMD) and outlines of the role of botulinum toxin (BoNT) in the treatment of myofacial TMD. This manuscript includes a brief history of the use of BoNT in the treatment of pain, the mechanism of action of BoNT, and the techniques for injections, adverse effects and contraindications when using BoNT to treat mayofacial pain caused by TMD.

Interventions for the treatment of Frey's syndrome

BACKGROUND

Frey's syndrome is a rare disorder, the symptoms of which include sweating, flushing and warming over the preauricular and temporal areas following a gustatory stimulus. It often occurs in patients who have undergone parotidectomy, submandibular gland surgery, radical neck dissection, infection and traumatic injury in the parotid region, and is caused by the aberrant regrowth of facial autonomic nerve fibres. Currently there are several options used to treat patients with Frey's syndrome; for example, the topical application of anticholinergics and antiperspirants, and the intradermal injection of botulinum toxin. It is uncertain which treatment is most effective and safe.

OBJECTIVES

To assess the efficacy and safety of different interventions for the treatment of Frey's syndrome.

SEARCH METHODS

We searched the Cochrane Ear, Nose and Throat Disorders Group Trials Register; the Cochrane Central Register of Controlled Trials (CENTRAL); PubMed; EMBASE; CINAHL; Web of Science; ICTRP and additional sources for published and unpublished trials. The date of the search was 28 April 2014.

SELECTION CRITERIA

We included randomised or quasi-randomised controlled trials (RCTs) in participants diagnosed with Frey's syndrome using a clinical standard such as Minor's starch-iodine test. We planned to include trials in which participants received any intervention versus no treatment (observation) or an alternative intervention, with or without a second active treatment. Our primary outcome measures were success rate (as assessed clinically by Minor's starch-iodine test, the iodine-sublimated paper histogram method, blotting paper technique or another method) and adverse events. Our secondary outcome measure was success rate as assessed by patients (disappearance or improvement of symptoms).

DATA COLLECTION AND ANALYSIS

We used the standard methodological procedures expected by The Cochrane Collaboration.

MAIN RESULTS

We identified no RCTs or quasi-RCTs that fulfilled the inclusion criteria. Our searches retrieved eight potentially relevant studies, but after assessment of the full-text reports we excluded all of them due to the absence of randomisation or because the patients did not have Frey's syndrome. We excluded one randomised controlled trial that compared two different doses of botulinum toxin in patients with Frey's syndrome because the comparator was not an alternative treatment.

AUTHORS' CONCLUSIONS

We are unable to establish the efficacy and safety of the different methods used for the treatment of Frey's syndrome.RCTs are urgently needed to assess the effectiveness of interventions for the treatment of Frey's syndrome. Future RCTs should include patients with Frey's syndrome of different ranges of severity and report these patients separately. Studies should investigate all possibly effective treatments (such as anticholinergics, antiperspirants and botulinum toxin) compared to control groups using different treatments or placebo. Subjective assessment of Frey's syndrome should be considered as one of the outcome measures.

Intradermal botulinum toxin a for peristomal hyperhidrosis: a case study

BACKGROUND

Peristomal hyperhidrosis can interfere with pouch adherence, resulting in pouch leakage and peristomal skin damage.

CASE

A patient with autonomic dysregulation resulting in excessive sweating (hyperhidrosis) experienced difficulty with adherence of her ileostomy appliance. Two hundred units of botulinum toxin A (BTX-A) were injected in the dermis of the surrounding skin in order to improve adherence of her pouching system and alleviate moisture of her peristomal skin.

RESULTS

Following BTX-A injection, the typical wear time of her pouching system improved from less than 24 hours to 120 hours. Peristomal moisture-associated skin damage resolved almost completely. These effects lasted 3 months. A repeat intradermal BTX-A injection had a similar positive effect.

CONCLUSION

Peristomal hyperhidrosis can be controlled with BTX-A intradermal injections, improving patient pouch adherence and alleviating moisture-associated skin damage.

Facial nerve paralysis and frey syndrome in an infant following removal of an internal mandibular distraction device

Mandibular distraction using an implantable device has become a widely accepted and utilized procedure for the treatment of retrognathia. Although excellent results have been reported and observed with distraction osteogenesis, complications such as facial nerve injury have been previously reported. Often, this injury is usually temporary and corrects over the course of time. Frey syndrome has been classically described as an injury or severance of the auricotemporal branch of the trigeminal nerve. It is commonly seen as a complication of parotid surgery and has never been reported in association with mandibular distraction. The authors report a unique case of both facial nerve paralysis and Frey syndrome in a patient following the removal of an internal mandibular distraction device. A review of the literature along with diagnosis and management are discussed.

Frey's syndrome: diagnosis in geriatric dentistry

Frey's syndrome, is characterized by warmth, flushing and sweating of the face, most of time in the preauricular region, initiated by any gustatory stimulus. It is frequently related to parotid surgery. A case of Frey's syndrome in a 81-year-old female whose long-delayed clinical onset post-parotidectomy is presented.

An evidence-based review of botulinum toxin (Botox) applications in non-cosmetic head and neck conditions

Botulinum toxin (Botox) is an exotoxin produced from Clostridium botulinum. It works by blocking the release of acetylcholine from the cholinergic nerve end plates leading to inactivity of the muscles or glands innervated. Botox is best known for its beneficial role in facial aesthetics but recent literature has highlighted its usage in multiple non-cosmetic medical and surgical conditions. This article reviews the current evidence pertaining to Botox use in the head and neck. A literature review was conducted using The Cochrane Controlled Trials Register, Medline and EMBASE databases limited to English Language articles published from 1980 to 2012. The findings suggest that there is level 1 evidence supporting the efficacy of Botox in the treatment of spasmodic dysphonia, essential voice tremor, headache, cervical dystonia, masticatory myalgia, sialorrhoea, temporomandibular joint disorders, bruxism, blepharospasm, hemifacial spasm and rhinitis. For chronic neck pain there is level 1 evidence to show that Botox is ineffective. Level 2 evidence exists for vocal tics, trigeminal neuralgia, dysphagia and post-laryngectomy oesophageal speech. For stuttering, 'first bite syndrome', facial nerve paresis, Frey's syndrome, oromandibular dystonia and palatal/stapedial myoclonus the evidence is level 4. Thus, the literature highlights a therapeutic role for Botox in a wide range of non-cosmetic conditions pertaining to the head and neck (mainly level 1 evidence). With ongoing research, the spectrum of clinical applications and number of people receiving Botox will no doubt increase. Botox appears to justify its title as 'the poison that heals'.