A Review of the Surgical and Medical Treatment of Frey Syndrome

Prevalence of Frey syndrome following extraoral surgical treatment for mandibular fractures: a systematic review and meta-analysis

Our study aims to estimate the prevalence of Frey syndrome following open reduction and internal fixation (ORIF) for mandibular fractures. Two reviewers independently conducted a systematic literature search in the Medline and Scopus databases. The pooled prevalence with 95% confidence intervals (CI) was estimated, and quality assessment, outlier analysis, and influential analysis were performed. In total, fifteen eligible studies were included in this meta-analysis. One study was identified as critically influential. The overall prevalence of Frey syndrome following extraoral surgical treatment for mandibular fractures was estimated as 0.01% (95%CI 0%-0.7%) with moderate heterogeneity observed between studies. In the meta-regression analysis with continuous variables, no statistically significant association was observed. Despite the relatively low prevalence, the impact of Frey syndrome on affected individuals should not be underestimated. Additional research will provide a more comprehensive understanding of the underlying factors contributing to Frey syndrome, leading to improved preventive measures and treatment strategies. A better grasp of the prevalence and associated risk factors will aid in the development of guidelines to minimize the occurrence of this syndrome.

Brief Clinical Study: An Alternative Method to Prevent Frey Syndrome After Resection of Huge Masses in Parotis: De-epithelialized Skin Flap Use

Frey syndrome is still a significant problem in postparotidectomy patients 6 to 18 months after surgery. The most accepted theory of the pathogenesis of Frey syndrome is the aberrant regeneration theory. Creating a barrier between the remnant parotid gland and the overlying skin prevents Frey syndrome. A 51-year-old female patient who developed pleomorphic adenoma in the parotid gland was operated. After superficial parotidectomy, a barrier between the underlying postganglionic parasympathetic nerves in the deep parotid gland and the overlying cutaneous tissue was created with a local skin flap to prevent Frey syndrome. The patient was successfully treated, and she was followed up to 5 years. No postoperative complications were observed. No signs of Frey syndrome were found in follow-up. This case highlights that local skin flaps can be an innovative natural method as it is a quick and simple method to create this barrier in the presence of expanded skin.

Effect of human acellular dermal matrix (Megaderm™) on infra-auricular depressed deformities, Frey's syndrome, and first bite syndrome following parotidectomy: a multi-center prospective study

Background

Parotidectomy is the primary treatment for parotid gland tumors. However, complications may include a prominent facial scar or infra-auricular depressed deformity, Frey's syndrome, first bite syndrome, or other facial pain, numbness, and paralysis. Acellular dermal matrix (ADM) has been widely used to prevent these complications in parotid surgery, but there have been no prospective, multi-center trials documenting its efficacy. This study evaluates the effectiveness of ADM implantation in preventing infra-auricular depressed deformity, Frey's syndrome and first bite syndrome after parotidectomy.

Methods

We analyzed 51 cases of standard parotidectomy and 58 cases of parotidectomy with implantation of Megaderm™ ADM through prospective multicenter trial. Acute complications including infection, seroma, hematoma, skin necrosis, and acute parotid area pain were evaluated 1 week postoperatively. Clinician grading of Frey's syndrome and blinded clinician evaluation of infra-auricular depressed deformities were conducted at 3, 6, and 12 months. Patients evaluated subjective satisfaction with neck appearance, Frey's syndrome quality, and acute parotid area pain at 3, 6, and 12 months.

Results

There was a higher incidence of seroma in the Megaderm™ group than in the control group at week 1. The incidence and total clinician-evaluated Frey's syndrome scores were significantly lower in the Megaderm™ group than in the control group at 3, 6, and 12 months. Both the objective and subjective evaluations of the facial contour showed a better outcome in the Megaderm™ group compared to the control group at 3, 6, and 12 months. There were no significant differences between the groups in the patient-reported Frey's syndrome quality scores at 3, 6, and 12 months, but the Megaderm™ group reported significantly less acute pain than the control group.

Conclusions

ADM implantation can effectively reduce the occurrence of Frey's syndrome, infra-auricular depressed deformity, and first bite syndrome after parotidectomy. ADM may be especially advantageous in complex parotidectomy cases when significant complications are expected.

What is the best method for prevention of postparotidectomy Frey syndrome? Network meta-analysis

BACKGROUND

Prevention of Frey syndrome (FS) after parotidectomy using an interposition barrier has long been gaining a wide popularity; however, there is no clear evidence regarding which preventive technique is more effective. The aim of this network meta-analysis (NMA) is to answer the question: What is the best method for prevention of FS after parotidectomy?

METHODS

A comprehensive search of the PubMed, Embase, SCOPUS, and Cochrane library was conducted to identify the eligible studies. The outcome was the incidence of subjective Frey syndrome (SFS) and objective Frey syndrome (OFS). The Bayesian NMA accompanied with a random effects model and 95% credible intervals (CrIs) were calculated using GeMTC R package.

RESULTS

Thirty-four studies (n = 2987 patients) with five interventions, namely Alloderm (ADM), temporoparietal fascia (TPF), sternocleidomastoid muscle (SCM), superficial musculoaponeurotic system (SMAS), and free fat graft (FFG), were compared together and with no interposition barrier (NB). The results of NMA showed a statistically significant reduction in both SFS and OFS when ADM, TPF, SMAS, FFG, and SCM were compared with NB. No statistical differences were observed when comparing ADM, SCM, SMAS, FFG, and TPF. TPF ranked the best of all treatments (59.4%) and was associated with the least incidence of SFS; whereas ADM ranked the best of all treatments (61.1%) and was associated with the least incidence of OFS.

CONCLUSIONS

All interventions (TPF flap, ADM, FFG, SMAS, and SCM) were associated with a significant reduction in the incidence of FS when compared with NB. TPF and ADM showed the best outcome with the least incidence of SFS and OFS, respectively.

Evaluation of antioxidant and antimutagenic activities of aluminum chloride

Purpose:

Hemostatic agents are used to control hemorrhage and the gingival crevicular fluid for dental applications. In this study; the antimutagenic and antioxidant activities of aluminum chloride (AlCl3), a topical hemostatic agent used especially in the fields of dermatology and dentistry, were determined. To our knowledge, this is the first study that investigates these properties.

Materials and methods:

The antioxidant activity was determined by DPPH free radical scavenging and β-carotene-linoleic acid bleaching assays. The antimutagenic activity was evaluated with the Ames Salmonella/ microsome mutagenicity test using Salmonella typhimurium TA98 and TA100 strains.

Results:

The total antioxidant activity of AlCl3, determined by β-carotene bleaching assay was found to be 25.59 ± 2.55% and the DPPH scavenging activity of AlCl3 was determined as 17.49 ± 3.07%. AlCl3 showed not any mutagenicity at the tested concentrations by the AMES test used S. typhimurium TA98 and TA100. This drug demonstrated antimutagenic effects at the test concentrations and the strongest antimutagenic activity was observed on 1.25 mg·mL-1/plate concentration of AlCl3.

Conclusion:

AlCl3 showed potent antimutagenic and antioxidant activities and these properties are significant for dentistry and dermatology.

Use of botulinum toxin in Frey's syndrome

Frey's syndrome is the most common adverse event after parotidectomy, and usually, it appears after 6 months. In our case, symptoms appear 20 years from surgery, an uncommon condition. Intralesional botulinum toxin gives excellent results in therapy, regardless of the time elapsed between surgery and the first treatment.

The Effects of Superficial Musculoaponeurotic System Flap on the Development of Frey's Syndrome and Cosmetic Outcomes After Superficial Parotidectomy

Objective

To investigate the outcomes of superficial musculoaponeurotic system (SMAS) flap and classic techniques in superficial parotidectomy in terms of Frey's syndrome (FS) and cosmetic satisfaction.

Methods

In this study, a retrospective chart review of patients that underwent superficial parotidectomy was performed. These patients were divided into two subgroups: group 1 included patients in which the SMAS flap was harvested and group 2 comprised the remaining patients on whom classic superficial parotidectomy was performed. All the patients were evaluated clinically and with Minor's starch-iodine test for FS. For the evaluation of the cosmetic results, the patient's satisfaction was queried according to the incision scar and surgical field skin retraction/facial symmetry. Both groups were compared in terms of complications and numbness of surgical area.

Results

Fifty-five patients (31 male and 24 female) with a mean age of 50.19 years were included in the study. Thirty-two patients were in group 1 and 23 in group 2. Thirteen patients (23.7%) described as having FS and six of them were in group 1, while seven were in group 2. Minor's starch-iodine test was positive in nine patients in group 1 (28.1%) and six patients in group 2 (26.1%) (p=1.000). With regard to cosmetic satisfaction, eight patients (25%) stated mild discomfort from the incision scar and two patients (6.3%) stated cosmetic dissatisfaction for facial asymmetry in group 1. In group 2 for the same factors the number of patients were 11 (47.8%) and 2 two (8.7%), respectively (p=0.027). There were no statistically significant differences in means of complication and numbness (p>0.05).

Conclusion

According to our study results, there was no superiority between both the groups in terms of FS and incision scar satisfaction. We determined that there was a significant benefit of SMAS flap application in the prevention of volume loss and surgical area retraction.

Infantile Frey's syndrome

Frey's syndrome in children is rare and often erroneously attributed to food allergy. Here we describe a case of Frey's syndrome in an infant and provide a review of the literature. Awareness of this condition is important for the Otolaryngologist in order to avoid unnecessary medical costs and procedures and provide reassurance to both parents and primary care providers in the setting of this benign condition.

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.

[Radiation therapy for pleomorphic adenoma of the parotid]

Parotid pleomorphic adenoma is the most frequent tumor of salivary glands. The prognosis depends on the recurrences because they could lead to iatrogenic events (facial paralysis). Moreover the risk of malignant transformation increases with the number of local relapses. This article aims at reviewing histological and radiological criteria and the surgical techniques. To improve local control, adjuvant irradiation (in first intention or after recurrence) may be useful but is still controversial for benign tumors in young patients with a risk of radio-induced cancer. We listed studies in which adjuvant radiotherapy was used so as to define its place in the treatment strategy. Prognostic factors were found by some authors. Other studies have to be done before strong evidence-based recommendations are issued.

The Efficiacy of Sternocleidomastoid Muscle Flap on Frey's Syndrome via a Novel Test: Galvanic Skin Response

The aim of this study was to evaluate the effects of sternocleidomastoid (SCM) muscle flap on preventing Frey's syndrome by using, Galvanic skin responses (GSR). Fourty-three patients who underwent superficial parotidectomy were randomly divided into two groups and their GSR were recorded. SCM muscle flap was applied over the surgical area only in one group. Six months after the surgery, GSRs were remeasured. In addition, the patients completed a questionnaire regarding their complaints about clinical Frey's syndrome. Four patients had symptoms of clinical Frey's syndrome. Postoperative GSR measurements revealed no significant difference between two sides in flap group (p = 0.426) but higher in without flap group (p = 0.003). The patients with clinical Frey syndrome had significantly higher GSR values than the remaining patients. The SCM muscle flap was an effective method in preventing Frey's syndrome. Moreover, GSR test was highly sensitive and specific for diagnosis.

Free fat grafting in superficial parotid surgery to prevent Frey's syndrome and improve aesthetic outcome

Background:

Frey's syndrome and cosmesis are important considerations in parotid surgery. Placement of an interpositional barrier can prevent these complications; however, surgical technique and efficacy remain controversial.

Methods:

A prospective case series was collected comprising all patients undergoing primary superficial parotidectomy for benign pathology with abdominal free fat grafting between June 2007 and December 2010, performed by a single surgeon. A survey was also distributed to otorhinolaryngology consultants across Australia to assess current practice.

Results:

Twenty-eight patients were included. No patient had clinical symptoms of Frey's syndrome. Seventy-five per cent of patients were completely satisfied with their aesthetic outcome, 18 per cent scored 4/5 and the remaining 7 per cent (2 patients) scored 3/5. The survey revealed that 79 per cent of respondents did not use interpositional grafts.

Conclusion:

Abdominal free fat is ideal for grafting as it is an effective, safe, simple, accessible, fast and inexpensive method of providing an interpositional graft.

The sternocleidomastoid muscle flap for the prevention of Frey syndrome and cosmetic deformity following parotidectomy: A systematic review and meta-analysis

Approximately 34-86% of neoplasms of the salivary glands are located in the parotid gland and parotidectomy is the first-line treatment for parotid gland tumors. Frey syndrome and cosmetic deformity are common complications experienced by patients following parotidectomy and the sternocleidomastoid muscle flap (SCMF) is used to prevent them. Numerous studies have been performed to examine the effectiveness of the SCMF for the prevention of cosmetic deformity and Frey syndrome, however, they provide contradictory results and possess small sample sizes with consequently low statistical power. In order to evaluate the effectiveness of the SCMF for the prevention of Frey syndrome and cosmetic deformity following parotidectomy, we performed a systematic review and meta-analysis based on published randomized controlled trials (RCTs), which were identified using PubMed and CNKI databases, and references of studies up to August 2012 were included. Using these criteria, we yielded 11 RCTs. Following an independent assessment of the methodological quality of these studies and the extraction of data, a systematic review and meta-analysis was conducted. The results of the meta-analysis demonstrated that there was a significant trend towards a lower risk of objective incidence [67%; risk ratio (RR), 0.33; 95% confidence interval (CI), 0.16-0.67; P<0.01] and subjective incidence (66%; RR, 0.34; 95% CI, 0.16-0.75; P= 0.01) of Frey syndrome in the SCMF group. The sensitivity analysis also indicated that this result was significant. Due to the considerable variation between the included studies, a meta-analysis was not applicable to assess cosmetic deformity. Two RCTs demonstrated that the difference between the SCMF and no SCMF group was not statistically significant, while the other seven RCTs detected a statistically significant difference between the two groups. Publication bias was detected. In conclusion, based on currently available evidence, the use of the SCMF is benefical for the prevention of Frey syndrome, however, whether it is also benefical for cosmetic deformity remains inconclusive.

Two-stage surgical approach with dermofat graft and lipofilling for the treatment of established Frey syndrome and facial depression deformity

Frey syndrome and facial contour deformity commonly occur after parotid surgery. Although the treatment of established Frey syndrome has focused on medical solutions, surgical solutions to established Frey syndrome have been less reported. Moreover, these methods may not resolve the facial depression. In the presented case here, we used 2-stage surgical approach with dermofat graft and lipofilling for the treatment of established Frey syndrome and facial depression deformity. We considered that this technique provides the easiest, most practical, satisfying, and effective solution for Frey syndrome that develops in the late follow-up period after superficial parotidectomy.

Delayed Frey syndrome after closed treatment of condylar fracture

Frey syndrome is also known as auriculotemporal syndrome and gustatory sweating. It is characterized by the occurrence of hyperesthesia, flushing, and warmth or sweating over the distribution of the auriculotemporal nerve and/or greater auricular nerve while eating foods that produce a strong salivary stimulus. It is commonly seen as a complication of parotidectomy and open surgery of temporomandibular joint. It can also be caused by other forms of trauma, including blunt trauma, but rarely does it occur without trauma. The relation between fracture displacement of the condyle and Frey syndrome adds further support to the view of the intimate anatomic relationship of the auriculotemporal nerve with the capsule of the temporomandibular joint. However, despite the proximity of these structures and the high incidence of condylar fracture (25%-36% of mandibular fractures), Frey syndrome is rare after this type of fracture. Symptoms are sometimes delayed and can be very slight; often neither the patient nor the surgeon realizes their presence. The symptoms usually appear 5 weeks to 1 year after nerve damage.In this clinical report, we presented the delayed occurrence of Frey syndrome in a patient in 6 years after closed reduction of condylar fracture. One prospective study and 11 case reports describing the development of Frey syndrome after closed treatment of mandibular condyle fractures were found in the last 4 decades. Our clinical report participates to literature as a 12th case report.

Lucja Frey (1889–1942): life destroyed by the Holocaust--on the 70th anniversary of her death

Lucja Frey was the first to explain the pathogenesis of the auriculotemporal syndrome, and the syndrome is recognized today as the Frey syndrome. Patients with this disease are subjected to paroxysmal paraesthesia of half of the face combined with sweating and redness. This syndrome can be found in the differential diagnosis of contemporary dermatology. Among others, it is differentiated from food allergies. The life and scientific career of Lucja Frey was brutally interrupted by the tragic times of the Holocaust.

AlloDerm implants for prevention of Frey syndrome after parotidectomy: a systematic review and meta-analysis

Although Frey syndrome is not life-threatening, it is identified as the most serious and widely recognized sequela of parotidectomy and has significant potential negative social and psychological implications. Several studies have investigated whether AlloDerm® implants prevent Frey syndrome effectively and safely, however, the conclusions are inconsistent. We aimed to evaluate the precise effectiveness of AlloDerm implants for preventing Frey syndrome after parotidectomy, using a systematic review and meta-analysis. We searched randomized and quis-randomized controlled trials in which AlloDerm implants were compared to blank controls for preventing Frey syndrome after parotidectomy, from the PubMed, Embase, the Cochrane Library and the ISI Web of Knowledge databases, without any language restriction. Two reviewers independently searched, identified, extracted data and assessed methodological quality. Relative risks with 95% confidence intervals were calculated and pooled. Five articles involving 409 patients met the inclusion criteria. Meta-analyses showed a significant 85% relative risk reduction in objective incidence (RR=0.15, 95% CI 0.08-0.30; P<0.00001) and 68% in subjective incidence (RR=0.32, 95% CI 0.19-0.57; P<0.00001) of Frey syndrome with AlloDerm implants; there was a significant 91% relative risk reduction in salivary fistula (RR=0.09, 95% CI 0.01-0.66; P=0.02); there was no statistical significance for the incidence of facial nerve paralysis (RR=0.96, 95% CI 0.84-1.09; P=0.51); there was no statistical significance for the incidence of seroma/sialocele (RR=1.36, 95% CI 0.66-2.80; P=0.40); there was a trend for a small effect in improving facial contour. Adverse events related to AlloDerm implants were not found. There is evidence that AlloDerm reduces the incidence of Frey syndrome effectively and safely, and also has the potential to improve facial contour and decrease salivary fistula. However, it is unclear whether AlloDerm implants improve facial contour and decrease other complications. Thus, further controlled evaluative studies incorporating more precise measures are required.

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

OBJECTIVE

Botulinum toxin is a widely accepted, effective treatment for Frey's syndrome. While some patients need only one injection, others require repeated treatments. We aimed to describe the clinical features of patients with a more challenging treatment course.

DESIGN

Literature review and retrospective analysis of eight consecutive patients treated at a university hospital.

SUBJECTS

These patients' treatment responses were categorised (using our own system) and compared with those of 25 published cases.

RESULTS

Combined analysis identified no significant correlation between treatment response and age, gender or the extent of primary salivary gland surgery. There was no significant correlation between botulinum toxin dosage and time between treatments.

CONCLUSION

Frey's syndrome should be viewed as a dynamic process in which the stimulus for aberrant reinnervation of parasympathetic nerve fibres can be reduced, in some patients, with higher botulinum toxin dose injections to the treated areas. However, responses are unpredictable, and relapses may occur at different time points and in different areas.

Familial auriculotemporal nerve (Frey) syndrome

Auriculotemporal nerve (Frey) syndrome in children is rare, and may be misdiagnosed as food allergy. Trauma to the auriculotemporal nerve during forceps-assisted delivery has been implicated in about half of the reported childhood Frey syndrome cases and most patients present with unilateral involvement. We describe two Caucasian sisters with bilateral Frey syndrome, neither of whom was delivered with forceps assistance, and highlight its distinction from food allergy. Frey syndrome may occur in a familial pattern, and in the absence of a history of perinatal trauma.