The use of human acellular dermal matrix in the prevention of infra-auricular depressed deformities and Frey's syndrome following total parotidectomy

Effects of acellular dermal matrix on the prevention of complications and esthetic outcome after parotidectomy: A propensity score matched analysis

OBJECTIVE

The present study was designed to investigate whether acellular dermal matrix (ADM) grafts could prevent Frey's syndrome (FS) and improve esthetic scores following parotidectomy.

METHODS

From January 2015 to December 2019, 175 patients underwent parotidectomy. We divided the patients into two groups: the ADM group and the control group. We included in each group 30 patients according to a propensity score matched analysis.

RESULTS

FS was subjective in 1 patient (3%) from the ADM group and 9 patients (30%) from the control group (P=0.015). Patients in the ADM group had a subjective esthetic score of 6.1 + 1.7 compared with 5.2 + 1.7 in the control group. The subjective esthetic score for patients in the ADM group was higher than that for patients in the control group (P =0.040).

CONCLUSION

The present clinical study suggests that ADM grafts are effective in preventing FS and improving esthetic scores after parotidectomy.

Management of Aesthetical and Functional Complications after Total Parotidectomy. First Long-Term Experiences with Dermal Matrix Surgimend ® in Patient Affected by Malignant Parotid Tumors

Background

This is an observational cohort study on patients affected by malignant parotid tumors treated with total parotidectomy. The aim of our work is to analyze and compare the effects and complications after parotidectomy, using or not SurgiMend ®.

Methods

40 patients were retrospectively enrolled between September 2014 and June 2020. Basing on the placement of SurgiMend ® for parotid lodge reconstruction, the samples were divided into two groups. Thus, the incidence rate of complications after the surgical procedure was analyzed between the two groups.

Results

Patients in whom SurgiMend ® was used reported a lower rate of complications. The ANOVA test (p = 0.05) revealed a significant difference of Vancouver Scar Scale (VSS) between the two groups, representation as vascularity and pigmentation improvement, changing scar color, scar height reduction, and increased pliability.

Conclusion

Although many techniques are available to fill the parotidectomy defect, improve facial contour and prevent Frey’s syndrome, the use of SurgiMend ® matrix is one of most effective and reliable method to address these complications, with the advantage of decreased operative time due to not require an additional surgical donor site.

Comparison of the use of allogenic acellular dermal matrix on rates of Frey syndrome post parotidectomy: A systematic review and meta-analysis

OBJECTIVE

The aim of this study was to evaluate the efficacy of acellular dermal matrix (ADM) use in reducing Frey syndrome (FS) rates in patients postparotidectomy.

STUDY DESIGN

We performed a systematic review and meta-analysis of existing literature comparing rates of FS with and without ADM use.

RESULTS

Eight studies were shortlisted for qualitative study, of which 7 compared rates of FS with and without the use of ADM. A total of 211 patients underwent parotidectomy with the use of ADM. Of these, mean patient age was 44.7 (SD ± 7.2); 89 of 159 were pleomorphic adenoma (55.9%), 29 of 159 with histological diagoses stated were Warthin's tumor (18.2%), and 159 of 211 were other histologic diagnoses (25.7%). Subjective and objective incidence rates for FS were 23 of 211 (10.9%) and 7 of 211 (3.3%), respectively. Patients in whom ADM barriers were used had significantly lower rates of subjective and objective FS (relative risk = 0.22; 95% confidence interval, 0.09-0.57; P = .002; and relative risk = 0.07; 95% confidence interval, 0.07-0.33; P < .001), respectively, compared to patients with no ADM.

CONCLUSION

The use of ADM was associated with lower FS rates compared to no ADM and should be considered in routine use to prevent this condition.

The Progress of Decellularized Scaffold in Stomatology

The oral and maxillofacial region contains oral organs and facial soft tissues. Due to the complexity of the structures and functions of this region, the repair of related defects is complicated. Different degrees of defects require different repair methods, which involve a great combination of medicine and art, and the material requirements are extremely high. Hence, clinicians are plagued by contemporary oral repair materials due to the limitations of bone harvesting, immune rejection, low osteogenic activity and other problems. Decellularized extracellular matrix has attracted much attention as a bioactive scaffold material because of its nonimmunogenic properties, good osteogenic properties, slow release of growth factors, promotion of seed cell adhesion and maintenance of stem cell characteristics. This article reviews the sources, preparation methods, application and research progress of extracellular matrix materials in the repair of oral and maxillofacial defects to provide an overview for fundamental research and clinical development.

Acellular dermal matrix for prevention of Frey's syndrome after superficial parotidectomy of benign tumors

PURPOSE

To evaluate: 1) the efficacy of acellular dermal matrix (ADM) to prevent Frey's syndrome (FS) after superficial parotidectomy of benign tumors. 2) the effect of different follow-up intervals on the incidence of FS.

METHODS

Fifty-five patients with benign parotid gland tumors underwent superficial parotidectomy were divided into two groups: Non-ADM group (n = 31, 56.3%) and ADM group (n = 24, 43.6%). The primary outcomes measure was the incidence of FS. The secondary outcomes were surgical site depression, infection, salivary sialocele, and salivary fistula. Subjective FS was evaluated using a clinical questionnaire submitted via WeChat at 3, 6, 12, 18, 24, and 32 months postoperatively. Objective FS was evaluated using Minor starch-iodine test at 6 and 12 months postoperatively.

RESULTS

There was a statistically significant difference in the incidence of subjective and objective FS when ADM compared with Non-ADM groups (P<0.05). The respective incidence of subjective FS at 3, 6, 12, 18, 24, and 32 months was 4.2%, 8.3%,20.8%, 20.8%, 20.8%, 20.8% in ADM group and 3.2%, 9.7%, 29%, 38.7%, 45.2% in Non-ADM group. The incidence of objective FS after 6 and 12 months was 4.2%, 8.3% in ADM group and 8.3% (2/24), 38.7% (12/31) in Non-ADM group respectively. Five patients in ADM group and 1 patient in Non-ADM group developed sialocele, and all patients resolved with conservative management. Surgical site depression was significantly higher in the Non-ADM group (15/31) compared with (5/24) in ADM (P=0.049). No cases of immune rejection, infection, hematoma, or salivary fistula were observed in ADM group.

CONCLUSIONS

The current study demonstrated that 1) ADM could reduce the incidence of FS in the patients undergoing superficial parotidectomy. 2) the peak onset of about 18 months appear to be acceptable follow-up for the development of FS.

Prevention of Frey's Syndrome with the Use of Porcine Dermal Collagen Graft: Retrospective Analysis of 76 "Formal" Parotidectomies for Benign Pathologies

BACKGROUND

Frey's syndrome is a well-known complication of parotid surgery; its prevention may be achieved by the use of an interpositional barrier between the overlying flaps and the exposed parenchymal bed of parotid gland. The aim of this study was to retrospectively evaluate clinical outcomes with and without the interpositional placement of a porcine dermal collagen graft (PDCG) for prevention of syndrome occurrence.

METHODS

We conducted a 20-year retrospective study including the patients who had undergone "formal" (superficial, total, or subtotal) parotidectomies for benign pathologies. The inclusion criteria also involved patients that were (i) regularly monitored about clinical symptoms related to syndrome, and (ii) examined with Minor starch-iodine test. The severity of the diagnosed syndrome was retrospectively evaluated according to the grading score system of Luna-Ortiz. To assess group differences in terms of the extent of dissection in operating sites, we estimated the tumor and histological specimen volumes using the available dimensions.

RESULTS

We included 73 patients who had undergone 76 formal parotid surgeries. The surgical sites were divided into 2 groups: (1) Group A consisted of 44 sites that were reconstructed with a SMAS flap, and (2) Group B, comprised 32 sites where a PDCG was additionally applied as an artificial preventive barrier. At a mean follow-up of 26.3 months, a significantly lower incidence of clinically diagnosed Frey's syndrome was found after the use of dermal collagen interpositional barrier (P = .031). Specifically, subjective symptoms were reported at an incidence of 31.8% in Group A and 6.7% in Group B. Minor's test was positive at an incidence of 59.09% in Group A and 21.87% in Group B (P = .004, 95% CI). Severe Frey's syndrome was observed in 31.82% of the patients of Group A and in 3.12% of the patients of Group B (P = .002, 95% CI). Since there were no statistical significant differences between the volumes of the removed tumors and the excised histological specimens, the extent of dissection was not proved to influence the occurrence of Frey's syndrome in the compared groups.

CONCLUSION

Porcine dermal collagen is a safe, practical, and useful means for parotid reconstruction, since it seems to contribute in prevention of Frey's syndrome when increased amount of glandular tissue has to be removed. Additional randomized controlled studies with bigger samples are required to better assess the PDCG use in parotid surgery.

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.

Different Surgical Strategies in the Prevention of Frey Syndrome: A Systematic Review and Meta-analysis

OBJECTIVE/HYPOTHESIS

To define the best surgical technique able to reduce Frey syndrome (FS) incidence after parotidectomy.

STUDY DESIGN

Systematic review and network meta-analysis.

METHODS

An arm-based network analysis was conducted using a Bayesian hierarchical model. The primary and secondary outcomes were the incidence of subjective (clinical) and objective (positive starch-iodine test result) FS, respectively.

RESULTS

A total of 3830 patients with a median age of 50.35 years (n = 2323; IQR 44.25-54.18) were included for six interventions [temporoparietal fascia (TPFF), free fat graft (FFG), acellular dermal matrix (ADM), sternocleidomastoid muscle (SCM) flap, and superficial musculoaponeurotic system (SMAS) flap]. If compared to no treatment, the greatest reduction of subjective (clinical) FS incidence was measured for the TPFF (OR: 0.07, CI: 0.004-0.57), the ADM (OR: 0.09, CI: 0.02-0.35), and the FFG (OR: 0.11, CI: 0.03-0.42) techniques. However, a significant difference was measured also for the SCM flap (OR: 0.38, CI: 0.18-0.73) and for the SMAS flap (OR: 0.42, CI: 0.19-0.97). All treatments showed a significant reduction of the objective FS incidence if compared to no treatment (FFG, OR: 0.06, CI: 0.002-0.62; TPFF, OR: 0.07, CI: 0.01-0.33; ADM, OR: 0.11, CI: 0.03-0.44; SMAS, OR: 0.36, CI: 0.17-0.71; SCM, OR: 0.40, CI: 0.19-0.74).

CONCLUSIONS

TPFF, ADM, and FFG seem to be the best treatment strategies to prevent FS after parotidectomy. Further randomized controlled trials comparing these techniques should be conducted to define specific indications. Laryngoscope, 131:1761-1768, 2021.

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.

Minor Parotidectomy Complications: A Systematic Review

OBJECTIVES

To report descriptive statistics for minor parotidectomy complications.

METHODS

A systematic review was performed, selecting 235 studies for analysis. The incidence of complications was tabulated, and descriptive statistics calculated. Outlier studies, 1 standard deviation above the mean, were reexamined to determine potential causal factors for each complication. All studies were examined for statistically significant differences for any potential causal factor.

RESULTS

The pooled incidence of minor complications reported were hematoma 2.9% (95% confidence interval [CI]: 2.4-3.5), wound infection 2.3% (95% CI: 1.8-2.9), sialocele 4.5% (95% CI: 3.5-5.7), salivary fistula 3.1% (95% CI: 2.6-3.7), flap necrosis 1.7% (95% CI: 1.1-2.5), scar issues 3.6% (95% CI: 2.4-5.4), numbness 33.9% (95% CI: 25.6-43.4), and deformity 11.8 (95% CI: 6.9-19.5). Implants result in more wound complications, such as hematoma, sialocele, or salivary fistula. Sialocele and salivary fistula appear more frequently after less extensive parotid surgery, whereas hematoma, wound infections, flap necrosis, and aesthetic considerations are worse with more extensive resections.

CONCLUSIONS

Minor parotidectomy complications are more frequent than generally assumed and related to certain factors that should be investigated. Laryngoscope, 131:571-579, 2021.

Graft interposition for preventing Frey's syndrome in patients undergoing parotidectomy

BACKGROUND

Frey's syndrome is characterised by transient flushing and sometimes facial sweating in the area of the auriculotemporal nerve. It most commonly occurs after parotidectomy, but other causes may include submandibular gland surgery, mandibular condylar fracture, obstetric (forceps) trauma, sympathectomy and metabolic disease. Although the pathophysiology of Frey's syndrome remains controversial, the generally accepted hypothesis is that it occurs as the result of injury to the auriculotemporal nerve.There is currently no clear evidence to establish the efficacy and safety of the different methods used for the treatment of Frey's syndrome, therefore the prevention of this symptom during surgery is important. The main method used for prevention is the interposition of a graft between the skin flap and the parotid bed during surgery. Biomaterials, allograft or autograft can be used for this purpose.

OBJECTIVES

To evaluate the effects and safety of biomaterial, allograft or autograft interposition for the prevention of Frey's syndrome in patients undergoing parotidectomy, and to identify its effect on prevention and delayed occurrence.

SEARCH METHODS

The Cochrane ENT Information Specialist searched the Cochrane ENT Trials Register; Cochrane Register of Controlled Trials (CENTRAL; 2019, Issue 2); Ovid MEDLINE; Ovid Embase; CINAHL; Web of Science; ClinicalTrials.gov; ICTRP and additional sources for published and unpublished trials. The date of the search was 5 February 2019.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) in patients with parotid disease (including tumours, inflammation, trauma etc.) undergoing parotidectomy with a minimal follow-up period of six months. We planned to include trials with interventions including biomaterial, allograft or autograft interposition alone or in combination with other surgical techniques. We included trials that compared any graft interposition and no graft interposition, or different graft interpositions.

DATA COLLECTION AND ANALYSIS

We used the standard methodological procedures expected by Cochrane. Our primary outcome measures were incidence rate of Frey's syndrome assessed clinically (Minor's starch-iodine test) and other complications (postoperative infection, subjective painful or restricted cervical movement, scar spread, rejection of the graft, complications related to the donor site such as accessory nerve injury and haematoma). Our secondary outcome measures were incidence rate of Frey's syndrome assessed by participants (by questionnaire) and sweating area assessed by Minor's starch-iodine test. We used GRADE to assess the certainty of the evidence for each outcome.

MAIN RESULTS

We included three RCTs (124 participants), two of which we assessed as at high risk of bias and one at unclear risk of bias. All studies were hospital-based and recruited participants undergoing superficial parotidectomy. Most participants were diagnosed with benign lesions of the parotid gland. Participants were followed up for more than six months. The studies evaluated the two comparisons shown below:Sternocleidomastoid muscle flap versus no flapTwo studies assessed this comparison. Both assessed the effects of the sternocleidomastoid muscle flap procedure on the incidence rate of Frey's syndrome assessed clinically but neither showed a significant difference between groups (risk ratio (RR) 0.08, 95% confidence interval (CI) 0.00 to 1.23; 24 participants and RR 1.23, 95% CI 0.88 to 1.73; 36 participants; very low-certainty evidence). We did not pool the data due to the high heterogeneity (I² = 87%).One study found that the sternocleidomastoid muscle flap may result in little or no difference in other complications including haematoma (RR 2.18, 95% CI 0.09 to 50.16; 36 participants; low-certainty evidence), subjective painful or restricted cervical movement (RR 0.54, 95% CI 0.14 to 2.05; 36 participants; low-certainty evidence) and scar spread in the cervical region (RR 0.71, 95% CI 0.05 to 10.54; 36 participants; low-certainty evidence). Both studies reported the incidence rate of Frey's syndrome assessed by participants, with one reporting no events in either group and the other finding no evidence of a difference (RR 0.63, 95% CI 0.32 to 1.26; 36 participants; low-certainty evidence).Acellular dermal matrix versus no graftOnly one study assessed this comparison. Use of an acellular dermal matrix graft may result in little or no difference to the incidence rate of Frey's syndrome (assessed clinically) in comparison with the no graft group, but the evidence is very uncertain (RR 0.08, 95% CI 0.00 to 1.25; 30 participants; very low-certainty evidence).Acellular dermal matrix may slightly increase the wound infection rate compared with control (RR 17.00, 95% CI 1.02 to 282.67; 64 participants; low-certainty evidence). Acellular dermal matrix may result in little or no difference to the incidence of seromas or sialoceles (RR 2.33, 95% CI 0.66 to 8.23; 64 participants; low-certainty evidence). Acellular dermal matrix may result in little or no difference to the incidence rate of Frey's syndrome (assessed by participants) in comparison with the no graft group (RR 0.33, 95% CI 0.04 to 3.04; 64 participants; low-certainty evidence).

AUTHORS' CONCLUSIONS

The evidence for the effectiveness of graft interposition in preventing Frey's syndrome is of low or very low certainty. The use of acellular dermal matrix may be associated with an increase in the wound infection rate, and little or no difference in the incidence of seromas or sialoceles. Further studies are needed to draw reliable conclusions.

Acellular dermal matrix (Insuregraf) in the prevention of Frey's syndrome and surgical site depression after parotidectomy

BACKGROUND

Parotidectomy is the treatment of choice in many parotid tumors. Due to the extensive nature of the procedure, unfavorable complications such as gustatory sweating, surgical site depression are common. Various techniques using fascia, muscle or AlloDerm have been developed but debate still remains regarding its availability and affordability. We applied a newly developed acellular dermal matrix (Insuregraf) to the parotidectomy field to act as a physical barrier and to provide adequate filling effect for prevention of functional and aesthetic complications.

METHODS

From March 2010 to March 2017, 30 patients with parotid tumors underwent superficial parotidectomy. Twenty patients underwent only superficial parotidectomy. Ten patients had Insuregraf applied to the surgical site after superficial parotidectomy. We evaluated the incidence of Frey's syndrome, surgical site depression, and patient satisfaction rate in both groups.

RESULTS

The incidence of Frey's syndrome was lower in the Insuregraf group (0 vs. 2). Surgical site depression was also lower in the Insuregraf group (2 vs. 20). Satisfaction score for facial contour in Insuregraf group was 9.2 out of 10, which was comparable to 6.2 out of 10 in the control group.

CONCLUSION

Application of Insuregraf after superficial parotidectomy is an effective surgical procedure to prevent complications such as Frey's syndrome and surgical site depression. This technique is affordable and safe with no immune reactions. Above all this surgical method should be considered as an option for patients who are concerned about the contour of the face after surgery.

Mixed Tumor in Deep Lobe and Versatility of Acellular Dermal Matrix

Frey's syndrome and infra-auricular depressed deformities are the ones of the most common complications that can occur after total parotidectomy. We report 1 case of pleomorphic adenoma occurred in the deep lobe that obtained good results from using acellular dermal matrix (ADM) after total parotidectomy. A 24-year-old man visited the hospital with oval shape mass in right mandibular angle which of 4 cm in size was found in the deep lobe of right parotid gland from Magnetic resonance imaging scanning and a pleomorphic adenoma was suspected. A total parotidectomy was performed while preserving the facial nerve. The material known as ADM were placed in the depressed part from where the mass was removed, and the site was sutured. The surgery site was healed well without any complications such as Frey's syndrome or infra-auricular depressed deformities. The pathological result was confirmed as pleomorphic adenoma. In addition to these advantages, it does not have little potential of deformation by the gravity after the surgery, and there is no restraint on circulation, which makes fabrication free and each deformation into various shapes can be described as another advantage of the reconstruction using the ADM.

Effectiveness of platysma muscle flap in preventing Frey syndrome and depressive deformities after parotidectomy

BACKGROUND

Frey syndrome (FS) or depressive deformity (DD) occurring after parotidectomy significantly reduces a patient's quality of life. However, there seems to be no effective treatment strategy against these complications. In this study, we report our experience of using platysma muscle flap (PMF) to prevent the development of FS and DD after parotidectomy, and evaluate its effect subjectively and objectively.

METHODS

Superficial parotidectomy was performed for eight cases of parotid gland tumor, and a PMF was transferred to cover the site. The incidence of FS and DD were evaluated subjectively, using a questionnaire to the patients and board-certified reconstructive surgeons, and objectively, using Minor's starch-iodine test.

RESULTS

In seven patients, the defect could be completely covered with PMF, and none of them developed FS or obvious DD. However, in one patient, the defect could be only partially covered, and the patient developed complications in the exact site that the flap did not cover. Overall scores from the questionnaire were high in relation to both cosmetic and functional perspectives from most of the patients and all the surgeons. No patients had major postoperative complications requiring revision.

CONCLUSIONS

PMF can be useful to cover the defect and prevent complications after parotidectomy. PMF is relatively easy to perform with fewer complications; however, a complete coverage of the defect should be ensured to obtain optimal results.