Incidence of postoperative facial weakness in parotid tumor surgery: a tumor subsite analysis of 794 parotidectomies

Clinical diagnostic utility of ultrasound-guided fine needle aspiration biopsy in parotid masses

BACKGROUND

Fine needle aspiration (FNA) is a common diagnostic tool used in the initial evaluation of parotid masses. In the literature, variable diagnostic accuracy of FNA is reported. Therefore, when considering clinical management of these patients, the utility of FNA is unclear. The aim of this study was to determine the capability of ultrasound-guided FNA to differentiate between benign and malignant neoplasms. Further, the way in which FNA results affect clinical decision-making was assessed.

METHODS

Retrospective data were collected for all patients who underwent parotidectomy at a large Canadian tertiary care center between 2011 and 2016. Patient demographics, preoperative imaging reports, preoperative FNA results, and final pathological diagnosis were analyzed.

RESULTS

Of the 199 patients who underwent parotidectomy, 184 had preoperative ultrasound-guided FNA. There were a total of 13 non-diagnostic FNAs. In diagnosing malignancy, FNA had a sensitivity and specificity of 71.4% and 98.7%, respectively. The positive predictive value (PPV) was 83.3%. The negative predictive value was 97.5%. Of the non-diagnostic FNAs, 2 out of 13 (15.4%) were deemed malignant neoplasms on final pathology.

CONCLUSION

FNA is a useful adjunct in the work-up of parotid masses, but it should be used with caution. Due to limited sensitivity, it should not be relied upon as the sole determinant of a surgeon's management plan.

Development of a Machine Learning Algorithm to Forecast the Likelihood of Postoperative Neurological Complications in Patients With Parotid Tumors

Objective: The objective of this study was to create and verify a machine learning-driven predictive model to forecast the likelihood of facial nerve impairment in patients with parotid tumors following surgery. Methods: We retrospectively collected data from patients with parotid tumors between 2013 and 2023 to develop a prediction model for postoperative facial nerve dysfunction using 5 ML techniques: Logistic Regression (Logit), Random Forest (RF), XGBoost (XGB), Artificial Neural Network (ANN), and Support Vector Machine (SVM). Predictor variables were screened using binomial-LASSO regression. Results: The study had a total of 403 participants, out of which 56 individuals encountered facial nerve damage after the surgery. By employing binomial-LASSO regression, we have successfully identified 8 crucial predictive variables: tumor kind, tumor pain, surgeon's experience, tumor volume, basophil percentage, red blood cell count, partial thromboplastin time, and prothrombin time. The models utilizing ANN and Logit achieved higher area under the curve (AUC) values, namely 0.829, which was significantly better than the SVM model that had an AUC of 0.724. There were no noticeable disparities in the AUC values between the ANN and Logit models, as well as between these models and other techniques like RF and XGB. Conclusion: Using machine learning, our prediction model accurately predicts the likelihood that patients with parotid tumors may experience facial nerve damage following surgery. By using this model, doctors can assess patients' risks more accurately before to surgery, and it may also help optimize postoperative treatment techniques. It is anticipated that this tool would enhance patients' quality of life and therapeutic outcomes.

The efficacy of clinicopathological and imaging features in differentiating benign from malignant parotid micro- and minitumors: a retrospective analysis

OBJECTIVE

To compare clinicopathological and imaging features of micro- and minitumors of the parotid gland and provide a reference for preoperative prediction of benign vs malignant status.

STUDY DESIGN

Patients with parotid gland tumors treated surgically were selected. Relevant clinicopathological and imaging data were collected for patients with maximum tumor diameters ≤20 mm on preoperative computed tomography (CT). The lesions were divided into 2 groups, microtumors and minitumors, based on maximum tumor diameter. CT imaging features of benign and malignant tumors were compared through binary logistic regression analysis.

RESULTS

Microtumors and minitumors were categorized by maximum diameters <10 mm (n = 74) and 10-20 mm (n = 611), respectively. Benign and malignant minitumors exhibited significant differences in boundary, tumor density, margin morphology, spiculation margin, and CT values in the plain and arterial phase (P ≤ .027), resembling those found in typical malignant parotid gland tumors. However, no significant differences were observed between benign and malignant microtumors. Logistic regression analysis identified boundary, margin morphology, and spiculation margin as independent predictors of malignancy. The prediction model excelled in identifying benign lesions but was less successful in identifying malignancies.

CONCLUSION

Parotid gland minitumors had imaging features similar to typical larger malignant tumors. Active exclusion of the malignant risk and early surgical treatment is recommended for these tumors.

Intraoperative Facial Nerve Involvement in Parotid Tumours - A Retrospective Analysis in a Tertiary Care Centre

Purpose

The study aims to provide a comprehensive overview of the various malignant and benign parotid tumours and evaluate the predictive factors for intraoperative nerve involvement leading to facial palsy (FP).

Methods

It is a single-centre retrospective analysis for reviewing the involvement of facial nerve in post- parotidectomy patients. The clinical database from January 2012 to December 2020 was included in the study with a follow-up period of a minimum of 2 years. To maintain homogeneity, all squamous cell carcinomas of level 2 nodes involving parotid or residual/recurrent disease of the oral cavity requiring parotid dissection were excluded.

Results

A total of 248 patients (171 benign; 77 malignant) were evaluated with a mean age of 46.48 ± 10.76 years. The presence of malignancy increases the risk of FP (p = 0.027). 37 (14.92%) patients with FP were detected which included 34 with partial [32.35% in malignant; 62.16% in recurrent pleomorphic adenoma (RPA)] and 3 with total paralysis (66.67% in malignant; 33.33% in RPA). The recurrence of pleomorphic adenoma increases FP. While old age, larger size, hard fixed swelling with masseteric space (MS) infiltration appeared as risk factors for FP in malignant tumours (p = 0.047; p = 0.004; p < 0.00001 respectively).

Conclusion

Tumour size, malignancy, hard fixed mass, masseteric space infiltration, recurrence, and age > 45yrs have been statistically significant predictive factors for intraoperative facial nerve involvement leading to FP. The study also revealed that FP occurred more commonly when there was concurrent involvement of both superficial and deep lobes but was not statistically significant.

Acute Onset of Delayed Facial Nerve Paralysis After an Uncomplicated Total Parotidectomy for an Oncocytoma

Facial nerve injury is one of the most substantial potential sequelae of parotid surgery. Pulling, stretching, and otherwise disturbing the facial nerve during parotid surgery can lead to post-surgical neural paresis and consequential deficits in facial movement. Furthermore, transection of the main facial nerve trunk or its branches, either purposeful or incidental, can lead to complete paralysis of the related facial musculature. Facial nerve injury is often diagnosed immediately post-operatively as evident by deficits in ipsilateral facial motion on examination of the patient in the recovery unit or, at most, by one week post-operatively. Although delayed onset facial nerve paralysis is seen in traumatic injury and otologic surgery, it is uncommon that facial nerve paralysis presents late after parotid surgery in the absence of hematoma development, viral reactivation, or secondary insult. Here, we present the case of a 70-year-old man developing a delayed acute onset of hemi-facial paralysis 12 days after right-sided total parotidectomy for an oncocytoma; a facial nerve examination done immediately post-operatively and at the one-week post-operative follow-up was found to be normal. The patient was treated with two courses of high-dose oral steroids with close-to-complete resolution.

Post-parotidectomy facial nerve rehabilitation outcomes: Comparison between benign and malignant neoplasms

BACKGROUND

Facial nerve dysfunction can be a devastating trouble for post-parotidectomy patients.

OBJECTIVE

To assess rehabilitation outcomes concerning patients with post-parotidectomy facial nerve dysfunction, comparing benign versus malignant neoplasms.

METHODS

Prospective study enrolling adults who underwent parotidectomy with facial nerve sparing between 2016 and 2020. The Modified Sunnybrook System (mS-FGS) was used for facial assessments. Physiotherapy began on the first post-operative day with a tailored program of facial exercises based on Neuromuscular Retraining, to be performed at home 3 times/day. From the first outpatient consultation, Proprioceptive Neuromuscular Facilitation was added to the treatment of cases with moderate or severe facial dysfunctions.

RESULTS

Benign and malignant groups had a statistically significant improvement in mS-FGS (p < 0.001 and p = 0.005, respectively). There was no significant difference between groups regarding treatment duration or number of physiotherapy sessions performed. The history of previous parotidectomy resulted in more severe initial dysfunctions and worse outcome. Age over 60 years and initially more severe dysfunctions impacted the outcome.

CONCLUSION

Patients with benign and malignant parotid neoplasms had significant and equivalent improvement in postoperative facial dysfunction following an early tailored physiotherapy program, with no significant difference in the final facial score, treatment duration, or number of sessions required.

Facial nerve palsy following parotid gland surgery: A machine learning prediction outcome approach

Introduction

Machine learning (ML)-based facial nerve injury (FNI) forecasting grounded on multicentric data has not been released up to now. Three distinct ML models, random forest (RF), K-nearest neighbor, and artificial neural network (ANN), for the prediction of FNI were evaluated in this mode.

Methods

A retrospective, longitudinal, multicentric study was performed, including patients who went through parotid gland surgery for benign tumors at three different university hospitals.

Results

Seven hundred and thirty-six patients were included. The most compelling aspects related to risk escalation of FNI were as follows: (1) location, in the mid-portion of the gland, near to or above the main trunk of the facial nerve and at the top part, over the frontal or the orbital branch of the facial nerve; (2) tumor volume in the anteroposterior axis; (3) the necessity to simultaneously dissect more than one level; and (4) the requirement of an extended resection compared to a lesser extended resection. By contrast, in accordance with the ML analysis, the size of the tumor (>3 cm), as well as gender and age did not result in a determining favor in relation to the risk of FNI.

Discussion

The findings of this research conclude that ML models such as RF and ANN may serve evidence-based predictions from multicentric data regarding the risk of FNI.

Conclusion

Along with the advent of ML technology, an improvement of the information regarding the potential risks of FNI associated with patients before each procedure may be achieved with the implementation of clinical, radiological, histological, and/or cytological data.

Imaging of Facial Nerve With 3D-DESS-WE-MRI Before Parotidectomy: Impact on Surgical Outcomes

OBJECTIVE

The intra-parotid facial nerve (FN) can be visualized using three-dimensional double-echo steady-state water-excitation sequence magnetic resonance imaging (3D-DESS-WE-MRI). However, the clinical impact of FN imaging using 3D-DESS-WE-MRI before parotidectomy has not yet been explored. We compared the clinical outcomes of parotidectomy in patients with and without preoperative 3D-DESS-WE-MRI.

MATERIALS AND METHODS

This prospective, non-randomized, single-institution study included 296 adult patients who underwent parotidectomy for parotid tumors, excluding superficial and mobile tumors. Preoperative evaluation with 3D-DESS-WE-MRI was performed in 122 patients, and not performed in 174 patients. FN visibility and tumor location relative to FN on 3D-DESS-WE-MRI were evaluated in 120 patients. Rates of FN palsy (FNP) and operation times were compared between patients with and without 3D-DESS-WE-MRI; propensity score matching (PSM) and inverse probability of treatment weighting (IPTW) were used to adjust for surgical and tumor factors.

RESULTS

The main trunk, temporofacial branch, and cervicofacial branch of the intra-parotid FN were identified using 3D-DESS-WE-MRI in approximately 97.5% (117/120), 44.2% (53/120), and 25.0% (30/120) of cases, respectively. The tumor location relative to FN, as assessed on magnetic resonance imaging, concurred with surgical findings in 90.8% (109/120) of cases. Rates of temporary and permanent FNP did not vary between patients with and without 3D-DESS-WE-MRI according to PSM (odds ratio, 2.29 [95% confidence interval {CI} 0.64-8.25] and 2.02 [95% CI: 0.32-12.90], respectively) and IPTW (odds ratio, 1.76 [95% CI: 0.19-16.75] and 1.94 [95% CI: 0.20-18.49], respectively). Conversely, operation time for surgical identification of FN was significantly shorter with 3D-DESS-WE-MRI (median, 25 vs. 35 min for PSM and 25 vs. 30 min for IPTW, P < 0.001).

CONCLUSION

Preoperative FN imaging with 3D-DESS-WE-MRI facilitated anatomical identification of FN and its relationship to the tumor during parotidectomy. This modality reduced operation time for FN identification, but did not significantly affect postoperative FNP rates.

Extracapsular Dissection of Deep Lobe Parotid Mass Aided by Retromandibular Vein on Imaging: A Case Report

This report investigates the use of the retromandibular vein on imaging as a diagnostic tool for planning deep lobe parotid tumors. A unique aspect of this case is the performance of extracapsular dissection on a deep lobe parotid lesion, which is rare. Preoperative imaging showed a superficially displaced retromandibular vein, indicating a deeply seated tumor, which aided surgical planning. Under general anesthesia, extracapsular dissection was performed while protecting the facial nerve branches. The patient's postoperative course was uneventful, and the facial nerve was intact with no weakness.

Pre-treatment quality of life in patients with salivary gland cancer in comparison with those of head and neck cancer patients

INTRODUCTION

Salivary gland cancer (SGC) is a rare malignant tumor arising from the salivary glands, with a variety of clinical and biological behaviors different from head and neck cancer (HNC). Because of the rarity of SGC, there are limited data on pre-treatment quality of life (QoL). Therefore, we evaluated the pre-treatment QoL in SGC patients by stage and compared it with that of HNC patients.

METHODS

From a prospective registry of HNC patients (2016-2020), we selected 225 patients with SGC, and 912 patients with oral cavity (OC) and oropharyngeal cancer (OPC) who were diagnosed in the same period as the HNC control group. The European Organization for Research and Treatment of Cancer (EORTC) Quality of Life Questionnaire Core 30 (QLQ-C30) and HNC-Specific Module (H&N35) were used to assess QoL.

RESULTS

SGC patients had a statistically better baseline QoL (69.8 vs. 64.0), emotional (82.1 vs. 78.8), cognitive (92.0 vs. 88.7), and social function (86.3 vs. 80.5), and fewer symptoms than HNC patients. The estimated average QoL differences between SGC patient diagnosed at stages I and IV was -12.9. Especially, advanced-stage of tumors was associated with much lower role functioning and emotional functioning scores in SGC patients, compared to those in HNC patients, among females and of younger age.

DISCUSSION

Although the overall QoL score was higher in SGC patients than in HNC patients, specific domains were significantly affected in SGC patients according to the tumor stage. Females and those of younger age were more affected by severity of disease in SGC.

STUDY REGISTRATION

ClinicalTrials.gov Identifier NCT02546895.

Reliability of the 'M-Line' in the Prediction of the Facial Nerve Position in Patients with Parotid Neoplasms

Preoperative radiological assessment of parotid tumours represents a crucial step in the planning of a parotidectomy in order to avoid post-operative facial nerve paralysis. The purpose of this study is to determine the reliability of the novel 'M-line' in predicting the facial nerve position and compare it to various radiological methods in the same context. 66 patients whom had underwent parotidectomy for parotid tumours from January 2012 to February 2021 were analyzed. Parotid tumour location were identified using the retromandibular vein, facial nerve line, Conn's arc, Utrecht line and the 'M'-line were compared to the intraoperative location of parotid tumours.The 'M'-line is a novel hypothetical line (drawn between the lateral surface of the mandible to the lateral border of the mastoid process) used to identify the location of the facial nerve radiologically. The 'M-Line' and other methods of radiological assessments were associated with statistical significance in predicting if the parotid tumours were superficial or deep to the facial nerve (p-value < 0.05).The 'M-line' had demonstrated a sensitivity of 73.6% and 92.3% specificity.It had also yielded the highest accuracy (77.3%) in the prediction of the parotid tumour location in relation to the facial nerve. While the radiological lines represented by the Retromandibular vein,facial nerve line,Utrecht line and Conn's arc were statistically significant in predicting the location of the parotid tumour in relation to the facial nerve, the M-line was the most accurate and sensitive predictor in our study.The M-Line is a potentially useful tool to predict the location of the facial nerve in relation to a parotid tumour.

Is This Novel Incision for Benign Parotid Tumors the Answer for Improved Esthetics and Access?

Background

Incision scars and postoperative cosmesis are critical in the management of benign parotid tumors. Traditional incisions have a typical visible scar in the retromandibular area or require wide skin flaps.

Purpose

In this study, we introduced a new surgical approach called the tri-split flap approach and evaluated its technical feasibility and surgical outcomes.

Materials and Methods

Eleven patients with clinically benign parotid gland tumors underwent the tri-split flap approach and were followed for six to ten months postoperatively. Facial weakness, salivary fistula formation, first bite syndrome, earlobe numbness, and the subjective cosmetic results were evaluated.

Results

All tumors were completely excised, and the patients were highly satisfied with the esthetic outcome of the surgery. No patients developed wound dehiscence, facial nerve injury, or first bite syndrome during the follow-up period. One patient developed a minor salivary fistula that resolved after three weeks.

Conclusion

The tri-split flap approach not only provides adequate exposure of the surgical site to achieve complete resection of benign parotid gland neoplasms but also results in a very short and highly concealed post-operative scar. This technique is a potential surgical approach in parotidectomy.

Supplementary Information

The online version contains supplementary material available at 10.1007/s12663-021-01605-1.

Proposals for Standardization of Intraoperative Facial Nerve Monitoring during Parotid Surgery

Intraoperative facial nerve monitoring (FNM) has been widely accepted as an adjunct during parotid surgery to facilitate identification of the facial nerve (FN) main trunk, dissection of FN branches, confirmation of FN function integrity, detection of FN injury and prognostication of facial expression after tumor resection. Although the use of FNM in parotidectomy is increasing, little uniformity exists in its application from the literature. Thus, not only are the results of many studies difficult to compare but the value of FNM technology is also limited. The article reviews the current literature and proposes our standardized FNM procedures during parotid surgery, such as standards in FNM setup, standards in general anesthesia, standards in FNM procedures and application of stimulus currents, interpretation of electrophysiologic signals and prediction of the facial expression outcome and pre-/post-operative assessment of facial expressions. We hope that the FNM standardized procedures will provide greater uniformity, improve the quality of applications and contribute to future research.

Pattern of facial nerve palsy during parotidectomy: a single-center experience

OBJECTIVE

This study was performed to report and analyze the prevalence of permanent facial nerve paralysis following parotidectomy for various benign and malignant lesions in a single center.

METHODS

This single-center retrospective study included all patients who underwent parotidectomy (total and superficial) for benign and malignant tumors and chronic inflammatory diseases during a 6-year period. Patients who had previously undergone an operation of the parotid gland and those with preoperative facial weakness were excluded.

RESULTS

The study included 127 patients ranging in age from 14 to 83 years (median, 45.89 years). Most patients were female (n = 83, 65.4%). The most prevalent procedure was superficial parotidectomy (n = 117, 92.1%), followed by total parotidectomy (n = 6, 4.7%). The average operative duration was 138 minutes (range, 80-400 minutes). Histopathology revealed that 109 (85.8%) patients had benign tumors, 14 (11.0%) had malignant tumors, and 4 (3.1%) had chronic sialadenitis. Only two patients sustained an injury to the cervical branch of the facial nerve.

CONCLUSION

In this single-center experience of parotid surgery, the rates of transient and permanent facial paralysis were acceptably low at 9.0% and 1.6%, respectively, for all pathologies.

Morphofunctional regeneration by mesenchymal stem cell and IGF-1 inoculation in a model of facial nerve crush injury in rats

OBJECTIVE

To analyze the morphofunctional regeneration process of facial nerve injury in the presence of insulin-like growth factor-1 and mesenchymal stem cells.

METHODS

Fourteen Wistar rats suffered unilateral facial nerve crushing and were randomly divided into two groups. All received insulin-like growth factor-1 inoculation, but only half of the animals received an additional inoculation of mesenchymal stem cells. The animals were followed for 90 days and facial nerve regeneration was analyzed via spontaneous facial motor function tests and immunohistochemistry in the nerve motor nucleus.

RESULTS

The group that received the growth factor and stem cells showed a statistically superior mean in vibrissae movements (p < 0.01), touch reflex (p = 0.05) and eye closure (p < 0.01), in addition to better immunohistochemistry reactivity. There was a statistically significant difference in the mean number of cells in the facial nerve nucleus between the experimental groups (p = 0.025), with the group that received the growth factor and stem cells showing the highest mean.

CONCLUSION

The association between growth factor and stem cells potentiates the morphofunctional regeneration of the facial nerve, occurring faster and more effectively.

LEVEL OF EVIDENCE

4, degree of recommendation C.

Prospective Assessment of Intraoperative Facial Nerve Monitoring in Patients Undergoing Partial Parotidectomy

The most significant complication of parotid gland tumor surgery is facial weakness. This study compares the occurrence of transient facial palsy in patients with parotid gland tumors who underwent surgery without monitoring to those who underwent surgery with monitoring. The study’s aim was to investigate facial nerve function in patients undergoing parotidectomy as well as the effect of intraoperative facial nerve monitoring and the effect of certain risk factors on the surgery and onset of postoperative facial palsy. This prospective study included 100 patients who underwent parotidectomy. The study cohort was divided into two groups. Group I included 50 patients who underwent surgery without neuromonitoring and group II included 50 patients who underwent surgery with neuromonitoring. The neurological assessment was conducted using the House–Brackmann scale. Preoperatively and one month postoperatively, electroneuronography (ENoG) and blink reflex tests were done. The analyses showed a significant reduction of the compound muscle action potential (CMAP) amplitude of the orbicularis oculi and orbicularis oris muscles and prolonged R1 and R2 blink reflex latencies 1 month after surgery. On neurological and electrophysiological studies, the rate of postoperative transient facial nerve dysfunction was significantly different between the groups. Significantly more patients, operated with use of facial nerve monitoring, presented postoperatively normal nerve function (i.e., House–Brackmann grade I) compared to those who underwent surgery without monitoring (78% and 26%, respectively; $p<0.001$ ). Monitoring had a statistically significant impact on the prevalence of facial nerve conduction disorders in patients who underwent surgery, according to the blink reflex and ENoG studies. The duration of the surgical procedure was not affected by monitoring in any way. The clinical evaluation of facial nerve function (House–Brackmann scale) and some ENoG results 1 month after surgery were found to have a significant correlation. To summarize, using monitoring considerably reduced the negative impact of local factors and the prevalence of transient facial nerve palsy.

The potential applicability of facial nerve monitoring as a navigation tool in parotid gland surgery

OBJECTIVES

The aim of this study was to assess the relationship between the stimulation amplitude and the distance to the facial nerve.

METHODS

This study was designed as a prospective clinical study. A total of 20 patients (12 males, 8 females) were included. Partial superficial parotidectomy was performed in all patients with intraoperative facial monitoring. Measurements were made on the main trunk and major branches. Stimulation was started at 1 mA and incrementally increased to 2 and 3 mA's. The shortest distance creating a robust response (>100 mV) was recorded.

RESULTS

At 1 mA, 2 mA and 3 mA stimulation intensity, the average distance between the tip of the stimulation probe and the main trunk was 2.20 ± 0.76 mm (range 1-3 mm), 3.80 ± 0.95 mm (range 2-5 mm), 4.80 ± 1.05 mm (range 3-7 mm) respectively. The stimulus intensity was inversely proportional in respect to the distance between the nerve and the tip of the stimulus probe (P < .00). The same relation was present in the facial nerve major branch measurements (P < .00).

CONCLUSION

The proportional stimulation amplitude and distance to the facial nerve is thought to be a reliable auxillary method to assist the surgeon by facilitating the estimation of the distance to the facial nerve during extracapsular dissection and minimally invasive cases where the facial nerve isn't routinely dissected.

LEVEL OF EVIDENCE

Level 3.

Modified Blair Approach for the Treatment of Mandibular Condyle Fractures

PURPOSE

The management of fractures of the condyle of the mandible has been a topic of debate and still no consensus exists in the literature about the most appropriate approach. The objective of this study was to evaluate the efficacy and safety of the modified Blair approach for the open reduction and internal fixation of mandibular condyle fractures.

METHODS

A retrospective study was conducted on 18 patients with 20 mandibular condyle fractures from 2014 to 2020. All patients were treated surgically using the modified Blair approach. Postoperative occlusion status and mouth opening were assessed for treatment outcomes. Also, the rate of complications such as facial nerve paralysis, wound infection, hematoma, salivary fistula, Frey syndrome, and greater auricular nerve paraeesthesia evaluated.

RESULTS

Seventeen out of 18 patients (94.4%) achieved their original pretraumatic occlusion after the surgery. One patient (5.5%) had postoperative occlusal interference due to premature dental contact. The maximal postoperative interincisal distance was measured with a range between 33 and 41 mm (mean 37.6 mm). One patient (5.6%) had transient facial nerve palsy. Also, salivary fistula developed in 1 (5.6%) patient in the postoperative period.

CONCLUSION

The results of this study revealed that the modified Blair approach provides satisfactory clinical outcomes with low complication rates and may offer an alternative, safe, and effective method for open reduction and internal fixation of mandibular condyle fracture.

Kabat Rehabilitation in Facial Nerve Palsy after Parotid Gland Tumor Surgery: A Case-Control Study

Temporary facial nerve palsy after parotid tumor surgery ranges from 14 to 65%, depending on surgery, tumor type, and subsite. The study aimed to evaluate the role of Kabat physical rehabilitation in the outcomes of patients affected by severe facial nerve palsy following parotid gland surgery. The results and clinical data of two groups, Kabat and non-Kabat (control), were statistically compared. Descriptive statistics, the multiple linear regression model, difference in difference approach, and the generalized linear model were used. F-Test, Chi-square test, McFadden R-squared, and adjusted R-squared were used to assess the significance. The results showed that the House–Brackmann (HB) stage of patients who had physiotherapy performed were lower than the control group. The decrease of HB staging in the Kabat group at 3 months was −0.71 on average, thus the probability of having a high HB stage decreased by about 13% using Kabat therapy. The results are statistically significant, and indicated that when the Kabat rehabilitation protocol is performed, mainly in the cases of a high-grade HB score, the patients showed a better and faster improvement in postoperative facial nerve palsy.

Benign tumors of the superficial lobe of the parotid gland

Tumors of the parotid gland are a rare occurrence among head and neck tumors (only 3-8%), and the vast majority are benign. Most benign tumors of the parotid gland are pleomorphic adenoma (PA), followed by Warthin's tumor (WT) and they occur in the superficial lobe. The only reasonable treatment is considered to be total tumor removal, but the appropriate surgical approach remains a matter of controversy. Over time, it went from enucleation to superficial parotidectomy (SP) and then to extracapsular dissection (ECD). SP is often considered to be the "gold standard"; however, the risk of intraoperative damage to the facial nerve (FN) cannot be ignored. Lately, ECD - which does not expose the main trunk of the FN - has been regarded as a safe technique for the treatment of small benign parotid tumors.

PATIENTS, MATERIALS AND METHODS

The study retrospectively reviewed all parotidectomies for benign parotid tumors of the superficial lobe performed in the Department of ENT, Municipal Emergency Clinical Hospital, Timişoara, Romania, between January 2014 and December 2018. The following patient data were collected: age; sex; follow-up duration; extension of the resection; use of FN monitoring and lesion features, including position, pathology, and size. Preoperative investigation protocol included a computed tomography (CT) scan to assess the size and location of the tumor helping the treatment planning. The same surgical team performed both standard SP and ECD for the treatment of these tumors. All cases were confirmed as benign parotid tumors. Recurrences of any kind and tumors involving the deep lobe of the gland were excluded from the study. All patients underwent a macroscopically complete resection of the tumor. The main outcome was the postoperative complications in the two groups. Data regarding these complications were recorded on follow-up visits at one, six, 12 and 24 months.

RESULTS

Ninety-five patients with benign parotid tumors were operated by the same surgical team at the Department of ENT, Municipal Emergency Clinical Hospital, Timişoara, between January 2014 and December 2018 but only 89 (38 men and 51 women) met the follow-up criteria and were included in the study. Sixteen (18%) patients underwent ECD, and 73 (82%) patients underwent SP as a primary intervention. The mean lesion size for ECD group was 2.0±0.9 cm and 4.2±1.7 cm in the SP group, and it was statistically significant (p<0.05). As expected, the most common type of tumor was PA but the distribution between the groups was different: in the SP group, PA represents 83% (61∕73) of cases but only 44% (7∕16) of cases in the ECD group. Median follow-up time was comparable in the two groups - 33±8 months for the ECD group and 39±11 months for the SP group. There were also differences between the two groups regarding the postoperative complication rate. There were significantly more transient and permanent FN paralysis, transient and permanent great auricular nerve (GAN) dysfunctions and Frey's syndrome (FS) in the SP group.

CONCLUSIONS

A comparison between ECD and SP as surgical procedures for the treatment of benign tumors of the parotid seems inappropriate as their indications do not overlap. ECD showed similar effectiveness and fewer side effects than SP and can be considered the treatment of choice for small, superficial and/or marginal tumors located in the lateral lobe of the parotid gland.

Endoscopic and Robotic Parotidectomy for the Treatment of Parotid Tumors: A Systematic Review and Meta-Analysis

Background

The goal of this review was to introduce endoscopic/robotic parotidectomy (EP/RP) and compare EP/RP against conventional parotidectomy (CP) regarding the intraoperative and postoperative parameters in the treatment of parotid tumors.

Methods

A systematic literature search of medical databases (PubMed, Embase, and Cochrane Central Register of Controlled Trials) was performed from inception to November 2020 to generate relevant studies.

Results

A total of 13 eligible studies (572 patients) were included for systematic review, and 7 out of 13 comparable studies for the quantitative synthesis of outcomes. Patients who underwent EP were characterized by less intraoperative bleeding volume, shorter incision length, and higher satisfaction postoperatively (WMD, 95% CI, -42.80; - 58.23 to -27.37; p < 0.01; WMD, 95% CI, -5.64; -7.88 to -3.39; p < 0.01; SMD, 95% CI, 1.88; 1.46 to 2.31; p < 0.01, respectively). However, operative time and risk of facial palsy exhibited no significant differences (WMD, 95% CI, -11.17; -26.71 to 4.34; p = 0.16; OR, 95% CI,0.71; 0.39 to 1.32; p = 0.28, respectively).

Conclusions

Our findings suggest that the current evidence does not adequately support EP is equally safe and effective as CP. In certain selected cases, endoscopic technology has its unique advantages. For patients with strong cosmetic needs, endoscopic or robotic techniques may be an alternative through adequate preoperative evaluations.

Systematic Review Registration

International Prospective Register of Systematic Reviews, identifier CRD42020210299.

Correlation between Electrophysiological Change and Facial Function in Parotid Surgery Patients

This observational study investigated intraoperative electrophysiological changes and their correlation with postoperative facial expressions in parotidectomy patients with visual confirmation of facial nerve (FN) continuity. Maximal electromyography(EMG) amplitudes of the facial muscles corresponding to temporal, zygomatic, buccal and mandibular branches were compared before/after FN dissection, and facial function at four facial regions were evaluated before/after parotidectomy in 112 patients. Comparisons of 448 pairs of EMG signals revealed at least one signal decrease after FN dissection in 75 (67%) patients. Regional facial weakness was only found in 13 of 16 signals with >50% amplitude decreases. All facial dysfunctions completely recovered within 6 months. EMG amplitude decreases often occur after FN dissection. An amplitude decrease >50% in an FN branch is associated with a high incidence of dysfunction in the corresponding facial region. This study tries to establish a standard facial nerve monitoring (FNM) procedure and a proper facial function grading system for parotid surgery that will be useful for the future study of FNM in parotid surgery.

Prospective study on complications using different techniques for parotidectomy for benign tumors

OBJECTIVES

Long-term prospective studies on procedure-related complications after parotid surgery for benign neoplasms (BNs) are scarce. This is the first prospective study on the use of extracapsular dissection (ECD) for BNs, and it aimed to examine the incidence of postoperative complications after parotid surgery for BN.

METHODS

We collected data obtained in a prospective study of parotidectomy for BN at a university hospital and analyzed the transient and long-term complications.

RESULTS

The incidence rates of transient facial palsy immediately and 18 months after surgery were 15.0% and 3.7%, respectively. The rates of immediate postoperative facial palsy in patients who underwent ECD, partial superficial, superficial, and total parotidectomy were 5.8%, 29.3%, 20.0%, and 44.1%, respectively. Significant risk factors for facial palsy included multiple and larger lesions as well as surgery duration and extension.

CONCLUSIONS

Postoperative facial palsy remains a common complication after parotidectomy for BN and is associated with the extent of parotidectomy, presence of multiple neoplasms, and operative duration. The results of this study showed that ECD could be a safe technique for avoiding facial palsy. Level of Evidence: 2.

Surgical management of deep lobe parotid tumours with and without involvement of the parapharyngeal space

The diagnosis and treatment of deep lobe parotid tumours is challenging because of the complex surgical accessibility. There is a lack of studies describing the differences between deep lobe tumours that do and do not occupy the parapharyngeal space (PPS). Patients treated for deep lobe tumours occupying the PPS (PPS group) and not occupying the PPS (non-PPS group) were analysed retrospectively. A total of 227 patients were treated surgically for deep lobe parotid tumours between 1990 and 2019. Sixty patients (26.4%) presented with tumours that involved the PPS (PPS group), while 167 (73.6%) presented with tumours that did not occupy the PPS (non-PPS group). The majority of the PPS group tumours were removed using a transcervical or transcervical-transparotid approach. PPS group tumours were larger (P < 0.001), and tumour spill occurred more frequently in this group (benign tumours: P = 0.002; malignant tumours: P = 0.033). Complication rates did not differ between the PPS and non-PPS groups. A transcervical or transcervical-transparotid approach is the preferred method for the management of deep lobe parotid tumours that occupy the PPS in our practice. Tumour spill occurred more frequently in the PPS group, which is most probably due to the larger tumour size and more complex accessibility.

Comparison of Parotidectomy With Observation for Treatment of Pleomorphic Adenoma in Adults

Importance

There is no consensus regarding optimal management of pleomorphic adenoma in adults.

Objectives

To compare parotidectomy with observation for the management of pleomorphic adenoma in patients 50 years or older by age.

Design and Setting

This decision analytical model was performed from November 21, 2019, to June 15, 2020, using a Markov model. Model variables and ranges were selected based on a literature review. A 1-way sensitivity analysis was performed to evaluate the age threshold at which each algorithm, either upfront elective parotidectomy or observation, would be favored. A Monte Carlo probabilistic sensitivity analysis using variable ranges was then performed 5 times with patients in the model assigned a starting age of 50, 60, 70, 80, and 90 years to assess how age at diagnosis would be associated with the model results.

Main Outcomes and Measures

Model outcomes were measured with quality-adjusted life-years (QALYs).

Results

In the study models, the age thresholds at which observation became more beneficial than parotidectomy were 88.5 years for patients with superficial lobe tumors (5.37 QALYs in favor of parotidectomy below this age, and 5.37 QALYs in favor of observation above this age) and 83.4 years for patients with deep lobe tumors (7.51 QALYs in favor of surgery below this age, and 7.51 QALYs in favor of observation above this age). There was no significant difference in outcomes between parotidectomy and observation among patients aged 70 to 80 years.

Conclusions and Relevance

This study suggests that the outcomes associated with parotidectomy and observation are similar at 70 years or older among patients with pleomorphic adenoma and that observation may be the favorable treatment in that age group.

Long-Term Facial Nerve Outcome in Primary Parotid Cancer Surgery: A Population-Based Analysis

OBJECTIVES/HYPOTHESIS

To determine immediate postoperative and long-term facial nerve dysfunction after parotid cancer surgery, risk factors, and the role of facial reanimation surgery.

STUDY DESIGN

Population-based long-term analysis for all new primary parotid carcinoma cases in Thuringia from 1996 to 2019.

METHODS

Data of the cancer registries of Thuringia, a federal state in Germany, were analyzed in combination with hospital-based data on facial function.

RESULTS

About 477 patients (42.3% women; median age: 68 years) were included. It was observed that 6.7% had a preoperative facial nerve dysfunction, 11.7% received a radical parotidectomy, that is, that 5% had a normal preoperative facial function but needed radical surgery because of intraoperative detection of tumor infiltration into the facial nerve. About 10.2% received facial nerve reconstruction surgery. Immediate postoperative facial nerve dysfunction in the other patients was observed in 34.4% of the patients. Advanced T classification (odds ratio [OR] = 2.140; confidence interval [CI] = 1.268-3.611; P = .004) and neck dissection (OR = 2.012; CI = 1.027-3.940; P = .041) were independent risk factors for immediate postoperative facial nerve dysfunction. In addition, 22.0% showed no recovery during follow-up. Advanced T classification (OR = 2.177; CI = 1.147-4.133; P = .017) and postoperative radiotherapy (OR = 2.695; CI = 1.244-5.841; P = .012) were independent risk factors for permanent postoperative facial nerve dysfunction.

CONCLUSION

Patients with primary parotid cancer are at high risk for long-term facial nerve dysfunction. It seems that the possibilities of facial reanimation surgery needs to be utilized even more effectively.

LEVEL OF EVIDENCE

3 Laryngoscope, 2021.

The Chimeric Scapulodorsal Vascularized Latissimus Dorsi Nerve Flap for Immediate Reconstruction of Total Parotidectomy Defects With Facial Nerve Sacrifice: Building a New Program and Preliminary Results From 25 Cases

BACKGROUND

Total parotidectomy with facial nerve sacrifice creates 2 challenging reconstructive problems: restoration of facial contour and facial nerve rehabilitation. Strong evidence suggesting that vascularized nerve grafts are superior to nonvascularized nerve grafts motivated our team to develop a chimeric scapulodorsal flap combining the usual harvestable local tissues with the vascularized latissimus dorsi motor nerve (SD-LDVxN). We present our experiences developing a new program at University of California, San Diego, highlighting our first case here, and present preliminary retrospective results focusing on the functional outcomes of facial nerve reanimation.

MATERIALS AND METHODS

The first case performed in the United States was a 57-year-old woman with stage IVA left parotid adenoid cystic carcinoma and House-Brackmann grade 6 facial palsy. She underwent total parotidectomy with facial nerve sacrifice and a free chimeric SD-LDVxN flap reconstruction. She had an unremarkable postoperative course, and 3- and 6-month follow-up functional results are reported. Preliminary functional results from our total series of 25 patients were reported.

RESULTS

At her 3-month follow-up, she was a House-Brackmann 5 with a static eFACE score of 37, dynamic eFACE score of 31, and smile eFACE score of 48. At her 6-month follow-up, she was a House-Brackmann 5 with a static eFACE score of 50, dynamic eFACE score of 27, and smile eFACE score of 53. Preliminary results from our total series of 25 patients with an average of 5 years of follow-up were a House-Brackmann 2.5 and eFACE scores of 83.1 for static facial symmetry, 67.5 for dynamic facial symmetry, and 77.7 for smile score. Twenty of the 25 patients had postoperative radiotherapy. No local tumor recurrence had been reported. The average reinnervation time was 9 months and ranged from 3 to 15 months.

CONCLUSIONS

The SD-LDVxN flap is a highly resourceful solution to reconstruct complex parotid defects, especially those that sacrifice the facial nerve. The vascularized nerve graft allows for primary facial reanimation. Nerve recovery may be superior to what could be expected with a conventional nerve graft.

Deep Lobe Parotid Tumors: A Systematic Review and Meta-analysis

OBJECTIVE

We performed a systematic review and meta-analysis of deep lobe parotid tumors to evaluate their unique characteristics.

DATA SOURCES

PubMed/Medline, Embase, Web of Sciences, and Cochrane Library databases were queried for relevant literature.

REVIEW METHODS

Studies were individually assessed by 2 independent reviewers. Risk of bias was assessed with the Cochrane bias tool, GRADE criteria, and MINORS criteria. Results were reported according to the PRISMA guidelines. Statistical analysis was performed by comparing rates of malignancy between deep and superficial lobe tumors.

RESULTS

In total, 8 studies including 379 deep lobe parotid tumors met inclusion criteria. Mean age at diagnosis was 44.9 years. Computed tomography scan was the most common imaging modality. Preoperative diagnostic fine-needle aspiration was utilized in 39.4% of patients and demonstrated high sensitivity for malignant disease. The most common approach was subtotal parotidectomy with facial nerve preservation (58.9%). The rate of malignancy was 26.6%, which was significantly higher than that of the superficial lobe tumors in this study (risk ratio, 1.25; 95% CI, 1.01-1.56). The rate of temporary postoperative facial nerve weakness between deep and superficial lobe tumors was 32.5% and 11.7%, respectively.

CONCLUSION

Deep lobe parotid tumors had a 26.6% rate of malignancy. On meta-analysis, deep lobe tumors appeared to have higher rates of malignancy than superficial lobe tumors. Surgical excision of deep lobe tumors showed increased rates of temporary facial nerve paresis as compared with superficial lobe tumors. Computed tomography scan was the most common imaging modality. There were limited data regarding the utility of fine-needle aspiration.

Fascicular Turnover Flap: An Approach for Facial Nerve Reconstruction

ABSTRACT

Facial nerve injuries are a common complication associated with parotidectomy. These functionally debilitating injuries are conventionally treated with nonvascularized nerve grafting; however, this reconstructive modality produces moderate donor site morbidity and has limited efficacy for repairing large defects. In addition, nonvascularized nerve grafts are highly susceptible to radiotherapy and require a well-vascularized wound bed to produce adequate therapeutic results. The fascicular turnover flap, described by Koshima et al, utilizes a single fascicle to bridge two nerve endings that are in series with no donor site morbidity. Although studies have demonstrated this technique's efficacy, there is a paucity of data regarding its use in patients undergoing facial nerve reconstruction. Herein, we describe our early clinical experience using the fascicular turnover flap to reconstruct branches of the facial nerve in patients undergoing extensive parotidectomy. Our patients underwent successful reconstruction of the nerve defects produced by parotidectomy using the fascicular turnover flap. Despite postoperative radiotherapy, both patients demonstrated complete functional recovery at six months postoperatively. Although formal head-to-head studies are needed to compare the outcomes of this technique versus conventional nerve grafting for facial nerve reconstruction, our preliminary experiences suggest that the fascicular turnover flap is a viable modality of reconstruction with great potential.

Clinical outcomes of bulky parotid gland cancers: need for self-examination and screening program for early diagnosis of parotid tumors

Background

Early detection and diagnosis of parotid gland cancer (PGC) are essential to improve clinical outcomes, because Tumor-Node-Metastasis stage at diagnosis is a very strong indicator of prognosis in PGC. Nevertheless, some patients still present with large parotid mass, maybe due to the unawareness or ignorance of their disease. In this study, we aimed to present the clinical outcomes of bulky PGC (defined by a 4 cm cutoff point for T3–4 versus T1–2 tumors), to emphasize the necessity of a self-examination tool for parotid gland tumor.

Methods

We retrospectively reviewed 60 consecutive cases with bulky (equal to and greater than 4 cm in the longest diameter, determined radiologically) malignant tumors arising from the parotid gland from 1995 to 2016. The clinical and pathological factors were analyzed to identify risk factors for poor outcomes using Cox proportional hazard models. In addition, we designed a self-examination tool for parotid gland tumors, similar to breast self-examination for breast cancer detection.

Results

Patients with bulky parotid cancer showed 48.9% 5-year and 24.5% 10-year overall survival rates and a 47.9% risk of high-grade malignancy. The common pathological diagnoses were carcinoma ex pleomorphic adenoma (18.3%), adenocarcinoma (16.7%), mucoepidermoid carcinoma (16.7%), salivary duct carcinoma (16.7%), and adenoid cystic carcinoma (11.7%). Survival analyses revealed that tumor size (hazard ratio, HR = 1.262 upon increase of 1 cm, 95% confidence interval, 95%CI 1.059–1.502), lymph node metastasis (HR = 2.999, 95%CI 1.048–8.583), and high tumor grade (HR = 4.148, 95%CI 1.215–14.154) were independent prognostic factors in multivariable analysis. Functional preservation of the facial nerve was possible only in less than half of patients.

Conclusion

In bulky PGC, lymph node metastasis at diagnosis and high tumor grade indicated poor survival outcomes, and functional outcomes of the facial nerve were suboptimal. Thus, a public effort seems to be necessary to decrease these patients with bulky PGC, and to increase patients’ self-awareness of their disease. As a way of early detection, we proposed a parotid self-examination tool to detect parotid gland tumors at an early stage, which is similar to breast self-examination.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12885-021-07902-9.

Three-dimensional double-echo steady-state with water excitation magnetic resonance imaging to localize the intraparotid facial nerve in patients with deep-seated parotid tumors

PURPOSE

To assess the utility of three-dimensional double-echo steady-state with water excitation (3D-DESS-WE) imaging for localizing deep-seated parotid tumors in relation to the facial nerve.

METHODS

A prospective study comparing the surgical outcomes of parotidectomy with or without 3D-DESS-WE sequence is currently enrolling the patients. Magnetic resonance imaging data from the first 25 patients with 3D-DESS-WE sequence were reviewed. Visibility of the intraparotid facial nerve was independently assessed by two neuroradiologists. The diagnostic performance of the 3D-DESS-WE sequence for prediction of deep lobe involvement was compared with that of two conventional methods based on the retromandibular vein line (RMVL) and facial nerve line (FNL). The relationship between the tumor and the main trunk of the facial nerve was also evaluated on the 3D-DESS-WE sequence.

RESULTS

On 3D-DESS-WE images, the main trunk, temporofacial division, and cervicofacial division of the intraparotid facial nerve were visualized in 100% (25/25), 48% (12/25), and 36% (9/25) of patients, respectively. The diagnostic accuracy of the 3D-DESS-WE sequence for prediction of deep lobe involvement was 92% (23/25), which was significantly superior to that of the RMVL (68% [17/25]; p = 0.008) and FNL (64% [16/25]; p = 0.004) methods. The relationship between the tumor and the main trunk of the facial nerve was correctly predicted in 92% (23/25) of 3D-DESS-WE images.

CONCLUSION

By direct visualization of the facial nerve, the 3D-DESS-WE sequence improved the preoperative localization of the intraparotid facial nerve in deep-seated parotid tumors. This information may help better surgical planning for deep-seated parotid tumors.

Machine Learning Models for Predicting Facial Nerve Palsy in Parotid Gland Surgery for Benign Tumors

BACKGROUND

Despite the increasing use of intraoperative facial nerve monitoring during parotid gland surgery (PGS) and the improvement in the preoperative radiological assessment, facial nerve injury (FNI) remains the most severe complication after PGS. Until now, no studies have been published regarding the application of machine learning (ML) for predicting FNI after PGS. We hypothesize that ML would improve the prediction of patients at risk.

METHODS

Patients who underwent PGS for benign tumors between June 2010 and June 2019 were included.

RESULTS

Regarding prediction accuracy and performance of each ML algorithm, the K-nearest neighbor and the random forest achieved the highest sensitivity, specificity, positive predictive value, negative predictive value F-score, receiver operating characteristic (ROC)-area under the ROC curve, and accuracy globally. The K-nearest neighbor algorithm achieved performance values above 0.9 for specificity, negative predictive value, F-score and ROC-area under the ROC curve, and the highest sensitivity and positive predictive value.

CONCLUSIONS

This study demonstrates that ML prediction models can provide evidence-based predictions about the risk of FNI to otolaryngologists and patients. It is hoped that such algorithms, which use clinical, radiological, histological, and cytological information, can improve the information given to patients before surgery so that they can be better informed of any potential complications.

Risk factors for subsequent recurrence after surgical treatment of recurrent pleomorphic adenoma of the parotid gland

BACKGROUND

Recurrent pleomorphic adenoma (PA) can be a lifelong disease, and rates of subsequent recurrence are high.

METHODS

Patients between 2000 and 2015 were identified. Primary outcome was subsequent recurrence after surgical salvage.

RESULTS

Twenty-seven of 84 patients developed a subsequent recurrence. Risk factors for subsequent recurrence included a higher number of previous recurrences (P < .01), worse preoperative facial nerve function (P < .01), and deep parotid lesion(s) (P < .01). Interval since last surgery was protective (P < .01), specifically >10 years since last surgery (P < .01). For patients with a >10-year interval since their last surgery, the subsequent recurrence-free rate at 10 years follow-up was 80.2% vs 31.8%.

CONCLUSIONS

For patients presenting with a >10-year interval since their last surgery, subsequent recurrence rates are low, which may allow for as needed surveillance recommendations. For patients presenting with recurrent PA and ≤10 years since their last surgery, a closer surveillance is warranted.

Single-surgeon parotidectomy outcomes in an academic center experience during a 15-year period

OBJECTIVE

As large single-surgeon series in the literature are lacking, we sought to review a single-surgeon's experience with parotidectomy in an academic center, with a focused analysis of pathology, technique, and facial nerve (FN) weakness. Benchmark values for complications and operative times with routine trainee involvement and without continuous FN monitoring are offered.

MATERIALS AND METHODS

All patients who underwent parotidectomy, performed by D. G. D., for benign and malignant disease between January 2004 and December 2018 at an academic center were reviewed.

RESULTS

A total of 924 parotidectomies, with adequate evaluatable data were identified. The majority of patients had benign tumors (70.9%). Partial/superficial parotidectomy was the most common approach (65.7%). Selective FN branch sacrifice was rare (12.3%), but significantly more common among patients with malignant pathology (33.8% vs 3.5% for benign, P < .0001). Among patients with intact FN, post-operative short- and long-term FN weaknesses were rare (6.5% and 1.7%, respectively). These rates were lower among patients with benign tumors (5.4% and 1.3%). Partial/superficial parotidectomy for benign tumors was associated with a low rate of short- and long-term FN weaknesses (2.7% and 0.9%). Mean OR time was 185 minutes.

CONCLUSION

This is the largest single-surgeon series on parotidectomy, spanning 15 years. We demonstrate excellent long- and short-term FN paresis rates with acceptable operative times without regular use of continuous FN monitoring and with routine trainee involvement. These findings may provide valuable insight into parotid tumor pathology, FN outcomes, and feasibility and expectations of performing parotidectomy in an academic setting.

LEVEL OF EVIDENCE

4.

Reconstruction of Extensive Composite Parotid Region Oncologic Defects with Immediate Facial Nerve Reconstruction Using a Chimeric Scapulodorsal Vascularized Nerve Free Flap

BACKGROUND

 Cancer involving the parotid gland region may originates from parotid parenchyma itself or from locoregional organs and in rare cases, the facial nerve (FN) has to be sacrificed during tumor resection. In these cases, cancer extension often goes beyond the parotid compartment and requires extensive local resection responsible for complex multitissular defects. The goals of reconstruction may be summarized in the following two components: (1) restoration of the volumetric tissue defect and (2) FN reconstruction. The aim of this study is to describe our surgical technique and our cosmetic results using the chimeric scapulodorsal vascularized nerve (SDVN) flap to reconstruct extensive maxillofacial defects associated with FN sacrifice.

METHODS

 All patients undergone an extensive maxillofacial resection with FN sacrifice and primarily reconstructed with a SDVN flap were included. We classified the maxillofacial defects into six groups based on the type of resection. Intraoperative data including flap composition, topography of FN injury, length of nerve gap, and number of nervous anastomosis were recorded.

RESULTS

 Twenty-nine patients were included. Mean follow-up was 38.7 months. The harvested flaps included the SDVN combined with different components according to the defect group. A satisfactory volumetric restoration was obtained in 93% of cases. The mean number of distal nervous anastomosis was 4.5. The length of the vascularized grafted nerve ranged from 7 to 10 cm.

CONCLUSION

 This is largest series presented in literature on primary FN reconstruction utilizing a vascularized nerve graft. We believe that the chimeric SDVN flap should be highly considered for these cases due to its versatility. The surgeon is able to use single donor site available soft and hard tissues components along with a vascular motor nerve graft, which offers a great length and number of distal branches, and easily matches with the extracranial FN trunk and its peripheral ramifications.

Artificial Neural Network as a Tool to Predict Facial Nerve Palsy in Parotid Gland Surgery for Benign Tumors

(1) Background: Despite the increasing use of intraoperative facial nerve monitoring during parotid gland surgery or the improvement in the preoperative radiological assessment, facial nerve injury (FNI) continues to be the most feared complication; (2) Methods: patients who underwent parotid gland surgery for benign tumors between June 2010 and June 2019 were included in this study aiming to make a proof of concept about the reliability of an artificial neural networks (AAN) algorithm for prediction of FNI and compared with a multivariate linear regression (MLR); (3) Results: Concerning prediction accuracy and performance, the ANN achieved the highest sensitivity (86.53% vs 46.23%), specificity (95.67% vs 92.59%), PPV (87.28% vs 66.94%), NPV (95.68% vs 83.37%), ROC–AUC (0.960 vs 0.769) and accuracy (93.42 vs 80.42) than MLR; and (4) Conclusions: ANN prediction models can be useful for otolaryngologists—head and neck surgeons—and patients to provide evidence-based predictions about the risk of FNI. As an advantage, the possibility to develop a calculator using clinical, radiological and histological or cytological information can improve our ability to generate patients counselling before surgery.