Combined BTX-A and Collagen Membrane in Benign Parotid Enucleation: A Comparative Cohort Study

The goal of surgical treatment for benign parotid gland tumors is to remove the mass completely without causing facial nerve palsy. In recent years, limited parotidectomy is becoming a new standard procedure for benign tumors, replacing superficial parotidectomy, and excellent results equal to the old procedure are being reported.This study evaluates the postoperative results of 59 benign parotid tumors treated surgically between 1991 and 2001, then determined whether limited parotidectomy can become the new standard of surgical management for benign parotid tumor.In 39 of the 59 patients, we investigated the frequency of local recurrence, Frey's syndrome and facial palsy. The histopathological diagnosis was pleomorphic adenoma in 17, Warthin's tumor in 15 and miscellaneous tumor including cyst, lymphoepithelial lesion or other lesions in 7, respectively. Twenty-one patients underwent partial parotidectomy, 10 enucleation and 8 superficial parotidectomy, respectively. The postoperative follow-up duration ranged from 3 to 14 years with an average of 7.54 years.According to the results of this follow-up study, there was no recurrence with each surgical procedure. Frey's syndrome did not occur in any patient after partial parotidectomy compared to that in 3 patients (37.5%) after superficial parotidectomy. Four patients (19.0%) temporarily experienced in some degree of facial nerve weakness after partial parotidectomy.From these results, partial parotidectomy is thought to be a new trend in the surgical treatment of benign parotid tumor.

Periostin is involved in airway remodeling, salivary tumors, and various otolaryngological diseases. D-β-aspartic acid is the major isomer of D-aspartic acid found in the tissues of elderly individuals. In this study, we investigated the expression and role of D-β-aspartic acid and periostin in the formation of benign parotid tumors. The data of 36 patients (16 male and 20 female) who underwent parotid tumor resection between April 2017 and March 2022 and were clinically and pathologically diagnosed as having benign parotid tumors were included in this study. The mean age of the patients was 59.2 (range 26-82) years. Tumors were histologically classified as pleomorphic adenomas, Warthin's tumors, basal cell adenomas, oncocytomas, and myoepitheliomas. Increased D-β-aspartic acid expression was observed in the epithelium and stroma of benign parotid tumors. In the epithelium, D-β-aspartic acid was found in 35 of 38 samples (92.1%). In the stroma, it was found in 19 of 38 samples (50.0%). In the stroma of benign parotid tumors, increased expression of periostin was found in 32 of 38 samples (84.2%). Four periostin expression patterns were observed in benign parotid tumors: negative, superficial, infiltrative, and diffuse. Statistically significant differences were found between the expression pattern of D-β-aspartic acid in the stroma and the histological classification of benign parotid gland tumors. In addition, a statistically significant difference was found between the expression patterns of D-β-aspartic acid and periostin in the stroma. Our results suggest that D-β-aspartic acid and periostin may be involved in the pathogenesis of benign parotid gland tumors.

How can Frey's syndrome be prevented or treated following parotid surgery?

This study aimed to evaluate and compare the mechanical properties of platelet-rich fibrin (PRF) membrane with that of commercially available collagen membranes and chorionic membranes. The modulus of elasticity and hardness of PRF membrane, bovine collagen membrane, fish collagen membrane, and chorionic membrane were assessed using a universal testing machine. The in vitro degradation rate was assessed by placing these membranes on a temperature-controlled shaker set for one week. The degradation profiles were expressed as the accumulated weight loss of the membrane. A scanning electron microscope (SEM) evaluation of these membranes was done under both low and high magnification. One-way analysis of variance (ANOVA) and Tukey's post hoc tests were performed for statistical analysis. A statistically significant difference in the tensile strength and hardness of membranes was observed. Bovine collagen membrane had the highest strength (84.11 MPa and 16.46 MPa) followed by fish collagen membrane, chorionic membrane, and least for PRF membranes observed. The degradation rate at one week was highest for the PRF membrane (55.6%), followed by the fish collagen membrane (32.5%). SEM evaluation showed that the bovine collagen membrane had significantly higher numbers of collagen fibres compared to the fish collagen membrane and chorionic membrane. Bovine collagen membrane had the highest mechanical properties with the maximum amount of collagen fibre meshwork. Only the PRF membrane had cellular distribution in its composition, while the commercially available membrane had significantly higher numbers of collagen fibres with the total absence of cellular components.

Does center or surgeon volume influence adoption of minimally invasive versus open pancreatoduodenectomy? A systematic review and meta-regression

Aim The aim of this study was to evaluate in vivo the absorption rate of three membranes: bovine collagen (GenDerm, Baumer, Brazil), collagen (Genoss, Dentium, Korea) and porcine dermis membrane (Kytinon M.O.R., Asmopul, Argentina). The additional aims were to evaluate blood vessel penetration and fiber collagen penetration in the early wound healing process. Materials and Methods Four dogs were used for the study and the membranes were applied by subperiosteal placement and analyzed after 15, 30, 60 and 90 days. Results The absorption rate of 65% absorption. This bovine collagen membrane was completely absorbed after 90 days. At this time point absorption of the bovine collagen (Collagen®, Dentium, Korea) was >65%, while absorption of the porcine dermis (Kytinon®, Asmopul, Argentina) was found to be between just 35% and 65%. Conclusion Blood vessel penetration and fiber collagen penetration in the three membranes showed significant differences, with faster vascularization and collagen penetration in the more rapidly absorbed membranes.

Synchronous unilateral tumors of the parotid gland are found only rarely. The majority of these are multifocal Warthin's tumors (papillary cystadema lymphomatosum). The incidence is reported to range up to 12%. Malignant processes develop within a pleomorphic adenoma in about 6.6% of all cases. In a few cases, they also develop in a Warthin's tumor. Two coexisting benign parotid tumors of different histologic types are extremely rare. In this report we present a patient with an unilateral pleomorphic adenoma and a Warthin's tumor. It is the eleventh published case of this kind. The problems of diagnosis, differential diagnosis, and surgical therapy of benign multiple parotid tumors are discussed. The current literature is reviewed. Synchronous multiple Warthin's Tumors or multiple tumors of different histologic types in the same parotid gland are found rarely. Nevertheless careful preoperative diagnosis causing B-mode ultrasound as the primary imaging modality. Meticulous intraoperative inspection and palpation of the glandular tissue and periglandular lymph nodes is indicated. In order to ensure adequate tumor removal, the therapy of choice is a total or subtotal parotidectomy. We suggest careful preoperative diagnosis and meticolous intra-operative exploration in order to localize multifocal lesions of benign parotid tumors. This minimizes the chance of overlooking synchronous tumor foci, which would necessitate difficult revision surgery entailing a risk of injury to the facial nerve.

Use of allogenic acellular dermal matrix in prevention of Frey's syndrome after parotidectomy

ObjectiveTo retrospective analysis of the epidemiological and clinical characteristics of parotid gland tumors, and to explore the value of ultrasound in the differentiation of benign and malignant parotid gland tumors.MethodsThe clinical data of 350 patients with parotid gland tumors in our hospital from 2002 to 2022 were retrospectively analyzed. These patients were examined by ultrasound. The postoperative pathological test results were used as the “gold standard” to verify and analyze the value of color Doppler ultrasound in the differential diagnosis of benign and malignant parotid tumors (PT).ResultsThe male‐to‐female ratio of 350 patients with parotid gland tumors was 1.16:1. The age of patients ranged from 12 to 87 years old. Patients aged 40–65 years accounted for 54.6%, which was the most common age of parotid gland tumors. Among 350 cases, 259 were benign and 91 were malignant. The top three benign PTs were pleomorphic adenoma, Warthin tumor, and basal cell adenoma. The top three malignant tumors were mucoepidermoid carcinoma, acinar cell carcinoma, and adenoid cystic carcinoma. The specificity, sensitivity, accuracy, positive predictive value, and negative predictive value of ultrasonography in the diagnosis of benign and malignant parotid masses were 96.53%, 69.23%, 89.43%, 87.50%, and 87.72%, respectively.ConclusionThe pathological types of parotid gland tumors are complex and diverse. Ultrasonography has high accuracy in the diagnosis of PT, which can provide important evidence for the differentiation of benign and malignant PT, and then assist in the clinical selection of individualized surgical programs.

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

ObjectiveParotid gland neoplasms account for a large proportion of benign salivary gland tumors, with pleomorphic adenomas (PA) being the most common in the civilian population, followed by Warthin's tumor (WT). However, the distinct risk profiles of Veterans significantly influence the incidence and prevalence of salivary gland neoplasms. We investigated the diagnostic and management algorithms for benign parotid gland neoplasms in Veterans.MethodsRetrospective cohort study. Descriptive statistics were calculated using Microsoft Excel. Categorical variables were compared using chi square tests, and were reported with 95% confidence intervals, with statistical significance set at P < .05.ResultsThe study included 158 patients who underwent fine-needle aspiration (FNA) only, and 88 who had FNA followed by surgical intervention. Most patients were male (91%) and smokers (73%). WT was the most common overall (45%), followed by PA (16%). Patients with FNA or surgical pathology indicating WT were more likely to have a history of over 10 pack-years of tobacco use compared to those with lymphocytic tissue, cysts, or PA (58/68 [85.3%, 95% CI 76.9-93.7%] vs. 36/70 [51.4%, 95% CI 39.6-63.2%], P < .05; 39/46 [84.8%, 95% CI 74.4-95.2%] vs. 16/32 [50.0%, 95% CI 32.8-67.2%], P < .05). Concordance between FNA and final pathology was 87.5% (77/88; 95% CI, 80.6-94.4%). Surgical patients experienced low complication rates, with sialocele being the most common at 8% (7/88; 95% CI 2.3-13.6%).ConclusionOverall, WT was the most prevalent neoplasm and was strongly associated with heavy tobacco use. The high concordance between FNA and surgical pathology underscores the reliability of FNA as a diagnostic tool. These results support the use of FNA as a reliable tool that can guide patient counseling with greater confidence. Furthermore, the low complication rates observed post-surgery reinforce the safety of surgical management.

OBJECTIVE: To review the literature on postparotidectomy complications (facial nerve paralysis, Frey syndrome, "wound complications", and recurrence) and to obtain meaningful data on their incidence, physiopathology, and favoring factors. To analyze the incidence of postparotidectomy complications in a prospective trial. To develop new objective evaluation methods for facial motor function and Frey syndrome. METHODS: Seventy patients underwent parotidectomy between April 1994 and 1998. Several improvements of standard parotidectomy were introduced in order to decrease postparotidectomy complications.

Background:The aim of this study was to evaluate the mechanical properties of the platelet-rich fibrin (PRF) membrane and to compare these properties with that of commercially available collagen membranes used for guided tissue regeneration (GTR) procedures. Scanning electron microscopic (SEM) examination of PRF membrane was also performed to determine the cell distribution pattern within the different regions of the membrane.Materials and Methods:Modulus of elasticity and hardness of (i) PRF membrane (ii) bovine collagen membrane and (iii) fish collagen membrane were assessed by performing surface indentation test using T1 950 Triboindenter. The in vitro degradation tests were conducted by placing the (i) PRF membrane (ii) bovine collagen membrane and (iii) fish collagen membrane of equal sizes (10 mm × 5 mm) in 5 ml of pH 7.4 phosphate buffer solution on a shaker set at 40 rpm for 1-week. The degradation profiles were expressed as the accumulated weight losses of the membrane. SEM evaluation of the PRF membrane was done under both low and high magnification.Results:Young's Modulus of elasticity was found to be 0.35 GPa for PRF membrane, 2.74 GPa for bovine collagen membrane and 1.92 GPa for fish collagen. The hardness was 10.67 MPa for PRF membrane, 110.7 MPa for bovine collagen membrane and 90.5 MPa for fish collagen membrane. PRF membrane degraded by about 36% of initial weight after a 1-week in vitro shaking test. Fish collagen membrane degraded by about 8% of initial weight, bovine collagen membrane degraded by about 3% of initial weight. Dense clusters of platelets formed due to extensive aggregation, and few leukocytes were observed in buffy coat area.Conclusions:The preliminary findings from the assessment of the mechanical properties of PRF membrane showed that it was lacking in several desired properties when compared to commercially available collagen membranes. Lack of rigidity and faster degradation may limit its application in GTR procedures.

Introduction: Frey‘s syndrome (SF), auriculotemporal syndrome, is an often neglected complication occurring in 6–96% of patients after parotid gland surgery according to recent studies. It arises on the basis of aberrant ingrowth of parasympathetic fi bers into the sheaths of denervated sweat glands after auriculotemporal nerve damage. The syndrome is characterized by a triad of symptoms: sweating, redness and burning or even pain in connection with food intake. Diagnosing these problems is not a time-consuming process and there are a number of therapeutic options. However, the vast majority of approaches, whether surgical or non-surgical, have only a short-term effect and carry a number of complications. The application of botulinum toxin A (BTXA) represents a relatively simple, effective and safe treatment option consisting of intradermal application of the solution according to a predetermined Frey syndrome activation map. Objectives: Presentation and evaluation of pilot results of therapeutic application of BTXA in patients dia gnosed with Frey‘s syndrome. Material and methods: Retrospective analysis of a group of 5 patients who underwent parotid gland surgery of various extents at the Department of Otorhinolaryngology and Head and Neck Surgery, University Hospital at St. Anny in Brno between 2006 and 2019, in whom there was a signifi cant manifestation of SF symptoms on the basis of which BTXA was therapeutically applied. Results: Evaluating the subjective manifestations of SF in all patients in our cohort, after the application of BTXA, showed that the problems signifi cantly decreased from “annoying and reducing their quality of life” to “never” or “almost never” occurring. Objective results of the Minor test interpreted by SketchAndCalc showed a decrease in SF activation of 91.6% on average. Only two patients required re-administration of BTXA at 6 and 19 months intervals. No adverse reactions to BTXA were reported or observed with any of the patients. Conclusion: BTXA is an eff ective and safe way to treat patients with Frey‘s syndrome. Keywords: parotidectomy – Frey syndrome – auriculotemporal syndrome – gustatory sweating – botulinum A toxin

Preoperative botulinum toxin A (BTA) injection versus component separation techniques (CST) in complex abdominal wall reconstruction (AWR): A propensity-scored matched study