Deep learning-assisted diagnosis of benign and malignant parotid tumors based on ultrasound: a retrospective study.

BACKGROUND: To develop a deep learning(DL) model utilizing ultrasound images, and evaluate its efficacy in distinguishing between benign and malignant parotid tumors (PTs), as well as its practicality in assisting clinicians with accurate diagnosis. METHODS: A total of 2211 ultrasound images of 980 pathologically confirmed PTs (Training set: n = 721; Validation set: n = 82; Internal-test set: n = 89; External-test set: n = 88) from 907 patients were retrospectively included in this study. The optimal model was selected and the diagnostic performance evaluation is conducted by utilizing the area under curve (AUC) of the receiver-operating characteristic(ROC) based on five different DL networks constructed at varying depths. Furthermore, a comparison of different seniority radiologists was made in the presence of the optimal auxiliary diagnosis model. Additionally, the diagnostic confusion matrix of the optimal model was calculated, and an analysis and summary of misjudged cases' characteristics were conducted. RESULTS: The Resnet18 demonstrated superior diagnostic performance, with an AUC value of 0.947, accuracy of 88.5%, sensitivity of 78.2%, and specificity of 92.7% in internal-test set, and with an AUC value of 0.925, accuracy of 89.8%, sensitivity of 83.3%, and specificity of 90.6% in external-test set. The PTs were subjectively assessed twice by six radiologists, both with and without the assisted of the model. With the assisted of the model, both junior and senior radiologists demonstrated enhanced diagnostic performance. In the internal-test set, there was an increase in AUC values by 0.062 and 0.082 for junior radiologists respectively, while senior radiologists experienced an improvement of 0.066 and 0.106 in their respective AUC values. CONCLUSIONS: The DL model based on ultrasound images demonstrates exceptional capability in distinguishing between benign and malignant PTs, thereby assisting radiologists of varying expertise levels to achieve heightened diagnostic performance, and serve as a noninvasive imaging adjunct diagnostic method for clinical purposes.

Machine learning-based radiomics for histological classification of parotid tumors using morphological MRI: a comparative study.

OBJECTIVES: To evaluate the effectiveness of machine learning models based on morphological magnetic resonance imaging (MRI) radiomics in the classification of parotid tumors. METHODS: In total, 298 patients with parotid tumors were randomly assigned to a training and test set at a ratio of 7:3. Radiomics features were extracted from the morphological MRI images and screened using the Select K Best and LASSO algorithm. Three-step machine learning models with XGBoost, SVM, and DT algorithms were developed to classify the parotid neoplasms into four subtypes. The ROC curve was used to measure the performance in each step. Diagnostic confusion matrices of these models were calculated for the test cohort and compared with those of the radiologists. RESULTS: Six, twelve, and eight optimal features were selected in each step of the three-step process, respectively. XGBoost produced the highest area under the curve (AUC) for all three steps in the training cohort (0.857, 0.882, and 0.908, respectively), and for the first step in the test cohort (0.826), but produced slightly lower AUCs than SVM in the latter two steps in the test cohort (0.817 vs. 0.833, and 0.789 vs. 0.821, respectively). The total accuracies of XGBoost and SVM in the confusion matrices (70.8% and 59.6%) outperformed those of DT and the radiologist (46.1% and 49.2%). CONCLUSION: This study demonstrated that machine learning models based on morphological MRI radiomics might be an assistive tool for parotid tumor classification, especially for preliminary screening in absence of more advanced scanning sequences, such as DWI. KEY POINTS: • Machine learning algorithms combined with morphological MRI radiomics could be useful in the preliminary classification of parotid tumors. • XGBoost algorithm performed better than SVM and DT in subtype differentiation of parotid tumors, while DT seemed to have a poor validation performance. • Using morphological MRI only, the XGBoost and SVM algorithms outperformed radiologists in the four-type classification task for parotid tumors, thus making these models a useful assistant diagnostic tool in clinical practice.

Quantitative dynamic contrast-enhanced MRI and readout segmentation of long variable echo-trains diffusion-weighted imaging in differentiating parotid gland tumors.

PURPOSE: To evaluate the ability of quantitative dynamic contrast-enhanced (DCE)-MRI and readout segmentation of long variable echo-trains diffusion-weighted imaging (RESOLVE-DWI) in differentiating parotid tumors (PTs) with different histological types. METHODS: In this retrospective study, 123 patients with 145 histologically proven PTs who underwent both RESOLVE-DWI and DCE-MRI were enrolled including 51 pleomorphic adenomas (PAs), 52 Warthin's tumors (WTs), 27 other benign neoplasms (OBNs), and 15 malignant tumors (MTs). Quantitative parameters of DCE-MRI (Ktrans, Kep, and Ve) and the apparent diffusion coefficient (ADC) of lesions were calculated and analyzed. Kruskal-Wallis tests with Dunn-Bonferroni correction, logistic regression analyses, and receiver operating characteristic curve were used for statistical analyses. RESULTS: PAs exhibited a lowest Ktrans among these four PTs. WTs demonstrated the highest Kep and lowest Ve values. WTs and MTs showed lower ADCmin values than PAs and OBNs. The combination of Kep and Ve provided 98.1% sensitivity, 85% specificity, and 98.7% accuracy for differentiating WTs from the other three PTs. The ADCmin cutoff value of ≤ 0.826 yielded 80.0% sensitivity, 92.3% specificity, and 90.3% accuracy for the differentiation of MTs from PAs and OBNs. Ktrans with a cutoff value of ≤ 0.185 achieved a sensitivity, specificity, and accuracy of 84.3, 70.4, and 79.5%, respectively, for discriminating PAs from OBNs. CONCLUSION: The combination of quantitative DCE-MRI and RESOLVE-DWI is beneficial for characterizing four histological types of PTs.

A novel clinically-oriented classification of fine-needle aspiration cytology for salivary gland tumors: a 20-year retrospective analysis of 1175 patients.

BACKGROUND: When determining treatment strategy for a salivary gland tumor, assessing histology and malignancy grade before surgery is essential. Several new diagnostic classification systems for salivary gland cytology have recently been proposed. However, none incorporate histology and grade of malignancy. METHODS: We developed a new cytology classification system that incorporates histology and grade of malignancy of salivary gland tumors (OMC classification), consisting of 11 categories. Our OMC classification was applied to 1175 patients who had preoperative cytology and confirmed final pathological diagnosis available from the past 20 years at our hospital (benign tumor: 981 patients, malignant tumor: 194 patients). RESULTS: Based on the cytology, 729 patients (62.0%) had benign histology (Category 4-1), and 87 patients (7.4%) were diagnosed with grade of malignancy (Category 6-3 + 6-4). Based on the final pathological diagnosis, the accuracy rate of Category 4-1 and Category 6-3 + 6-4 of our classification system was 93.4% and 88.5%, respectively. CONCLUSION: Based on the correct diagnosis rate, the inclusion of histology and grade of malignancy in the salivary gland cytology classification was considered feasible. Thus, the OMC classification system is considered a useful tool when determining the treatment strategy for a salivary gland tumor.

Symptoms and signs of parotid tumors and their value for diagnosis and prognosis: a 20-year review at a single institution.

BACKGROUND: Detailed clinical features other than parotid mass have not been investigated in detail for parotid tumors. Symptoms and signs are useful for the differentiation of benign versus malignant, and may also be of value to determine the grade of malignancy and histological type as well as the assessment of prognosis. METHODS: We reviewed symptoms and signs of 965 patients with benign tumors and 200 patients with malignant tumors. Symptoms and signs included pain/tenderness, adhesion to surrounding tissues, and facial nerve palsy. We reviewed the incidence in benign and malignant tumors, in histological type of benign tumors, and in grade and histology of malignant tumors. For each symptom or sign, covariates were analyzed, and their correlation with the prognosis was investigated. RESULTS: The incidence of symptoms and signs was significantly higher in malignant than benign tumors, and more frequent in higher grade of malignancy. Facial nerve palsy was observed in 18.0% of malignant tumor cases, while none occurred in benign tumor cases. Pain/tenderness was more commonly observed in adenoid cystic carcinoma, while adhesion to surrounding tissues and facial nerve palsy were most frequently noted in salivary duct carcinoma. The prognosis of patients with these symptoms and signs was significantly poor. CONCLUSION: A detailed investigation of symptoms and signs in parotid gland tumors is the first step that leads to the diagnosis of malignant tumors. Symptoms and signs are also useful for estimating the grade of malignancy and histological type, and they are important information for predicting prognosis.

Histogram analysis of dynamic contrast-enhanced magnetic resonance imaging in the differential diagnosis of parotid tumors.

OBJECTIVE: Dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) histograms were used to investigate whether their parameters can distinguish between benign and malignant parotid gland tumors and further differentiate tumor subgroups. MATERIALS AND METHODS: A total of 117 patients (32 malignant and 85 benign) who had undergone DCE-MRI for pretreatment evaluation were retrospectively included. Histogram parameters including mean, median, entropy, skewness, kurtosis and 10th, 90th percentiles were calculated from time to peak (TTP) (s), wash in rate (WIR) (l/s), wash out rate (WOR) (l/s), and maximum relative enhancement (MRE) (%) mono-exponential models. The Mann-Whitney U test was used to compare the differences between the benign and malignant groups. The diagnostic value of each significant parameter was determined on Receiver operating characteristic (ROC) analysis. Multivariate stepwise logistic regression analysis was used to identify the independent predictors of the different tumor groups. RESULTS: For both the benign and malignant groups and the comparisons among the subgroups, the parameters of TTP and MRE showed better performance among the various parameters. WOR can be used as an indicator to distinguish Warthin's tumors from other tumors. Warthin's tumors showed significantly lower values on 10th MRE and significantly higher values on skewness TTP and 10th WOR, and the combination of 10th MRE, skewness TTP and 10th WOR showed optimal diagnostic performance (AUC, 0.971) and provided 93.12% sensitivity and 96.70% specificity. After Warthin's tumors were removed from among the benign tumors, malignant parotid tumors showed significantly lower values on the 10th TTP (AUC, 0.847; sensitivity 90.62%; specificity 69.09%; P < 0.05) and higher values on skewness MRE (AUC, 0.777; sensitivity 71.87%; specificity 76.36%; P < 0.05). CONCLUSION: DCE-MRI histogram parameters, especially TTP and MRE parameters, show promise as effective indicators for identifying and classifying parotid tumors. Entropy TTP and kurtosis MRE were found to be independent differentiating variables for malignant parotid gland tumors. The 10th WOR can be used as an indicator to distinguish Warthin's tumors from other tumors.

Effective surgical management of anterior tumors of the parotid gland: Main trunk method vs. peripheral Smethod.

OBJECTIVE: Several surgical procedures have been proposed for tumors in the anterior parotid gland. Although the standard approach to other parotid tumors is generally also used for anterior tumors, handling of the facial nerve has not been addressed in any previous reports. METHODS: A total of 654 patients with benign parotid tumors who underwent surgery in our department were classified into anterior (AT), middle (MT), and posterior tumor (PT) groups according to tumor location. Clinical characteristics, histopathological types, and frequency of postoperative transient facial palsy were examined. In the AT group, two surgical methods were compared, which were the main trunk method (MTM) and the peripheral method (PM). RESULTS: 172 patients were included in the AT group, 175 in the MT group, and 307 in the PT group. The AT group showed significant female predominance and a higher percentage of deep lobe tumors than the PT group. There was no significant difference in the rate of postoperative transient facial palsy among the AT (MTM), MT, and PT groups. The PM had a significantly shorter operating time and lower rate of transient facial palsy than the MTM. CONCLUSION: The PM for AT was considered a useful surgical method from the standpoints of postoperative complications and operating time. In the PM, a wide operating field made identification of the facial nerve easier.

Ultrasound-guided ethanol sclerotherapy for non-surgical treatment of Warthin's tumor.

BACKGROUND: Currently, the first line treatment for Warthin's tumor (WT) is parotidectomy. There is a paucity of data evaluating the safety and efficacy of non-surgical treatments for patients not amenable to surgery. Ultrasound guided ethanol sclerotherapy (UGES) has been successfully used for the management of lymphangiomans of the head and neck, thyroid nodules, and thyroid cysts. This is the first study to implement and assess the success of UGES for management of WT. METHODS: We report two patients with WT, with a total of 3 masses, who underwent UGES. All procedures were performed in the clinic. The primary outcome measured was the tumor volume reduction rate (VRR), patient satisfaction, and complications observed at follow-up. RESULTS: Both patients experienced a significant reduction in tumor size upon follow up. VRR for the three treated tumors were 67.30%, 98.32%, and 55.73%. Patient were very satisfied with the results and noted significant cosmetic improvement. No complications were observed at follow-up. CONCLUSIONS: Ultrasound guided ethanol sclerotherapy may be a viable option for conservative treatment of Warthin's tumor in patients unsuitable or unwilling to undergo surgical resection.

The role of fine needle aspiration biopsy in deep lobe parotid tumors: Comparison of preoperative cytology and postoperative histopathologic results.

PURPOSE: Major salivary gland tumors constitute almost 3% of head and neck tumors. Tumors located exclusively in the deep lobe are not common and 20% of parotid gland tumors originate from deep lobe under the branches of the facial nerve. Accuracy of fine needle aspiration biopsy (FNAB) procedure in salivary gland tumors have been studied extensively, however there isn't any data regarding usefulness of FNAB in tumors located exclusively in deep lobe of parotid gland. In this study we aimed to assess the use of FNAB in deep lobe parotid tumors. MATERIALS AND METHODS: We retrospectively analyzed 51 patients with deep lobe parotid tumors who underwent surgery in our clinic between January 2013-December 2018. Characteristics of patients were recorded. Preoperative FNAB results and postoperative final histopathologic diagnosis were compared. Statistical analysis was performed using SPSS 24.0 was used for statistical analysis. RESULTS: The number of patients that met the inclusion criteria was 51. The mean age of patients were 49.2(14-86). In 40 (78.4) of the patients, tumor was reported as benign and in 11 (21.6) patients FNAB diagnosis was suspicious for malignancy, malignant or non-diagnostic. In final histopathologic diagnosis, 42 of the tumors were benign and 9 were malignant. The most common benign tumor type was pleomorphic adenoma which constitutes 27 of the cases (52.9%). Regarding detection of malignant disease, the sensitivity of FNAB was 90.4%, specificity was 77.7%, positive predictive value was 95%, negative predictive value was 63.6%. There was a substantial agreement between FNAB and final histopathologic diagnosis(kappa = 0,628). CONCLUSIONS: FNAB is a safe and reliable tool to evaluate deep lobe parotid tumors. It is an important part of preoperative surgical planning and can help the surgeon in patient counseling. FNAB with ultrasound guidance is recommended for deep lobe tumors.

Increase in Chymase-Positive Mast Cells in Recurrent Pleomorphic Adenoma and Carcinoma Ex Pleomorphic Adenoma of the Parotid Gland.

Incomplete excision of pleomorphic adenoma (PA) may result in recurrent pleomorphic adenoma (RPA). Furthermore, long-term neglected PA may become carcinoma ex pleomorphic adenoma (CXPA). In the present study, the relationships between mast cell-derived chymase and these tumors were examined. The tumor tissues of PA consisted of either or both glandular and fibrotic structures. Histological features of RPA were almost similar to those of PA, except that they showed multinodular structures. CXPA is composed of a mixture of PA and carcinoma. The main stromal cells in PA were myofibroblasts, whereas fibroblasts constituted the main cellular portion in the stromal tissue of RPA. Cancer-associated fibroblasts (CAFs) were present abundantly in CXPA. With increased VEGF expression, neovascularization tended to increase in RPA or CXPA. Compared with PA, chymase-positive mast cells, as well as chymase gene expression, were increased in the tumor tissues from patients with RPA or CXPA. SCF, TGFß1, and PCNA-positive staining was widely observed in these tumor tissues. The above results suggest that mast cell-derived chymase through its direct or cooperative effects with other mediators may participate in the pathophysiology of RPA and CXPA.

The use of bipolar coagulation forceps prevented salivary fistula in patients with parotidectomy: a retrospective study.

BACKGROUND: Salivary fistula is a relatively common complication in patients who have undergone a parotidectomy. The purpose of this study was to investigate the effects of bipolar coagulation forceps use on salivary fistulas. METHODS: From March 2015 to June 2020, 177 patients who underwent a parotidectomy in the Department of Oral and Maxillofacial Surgery at the Second Xiangya Hospital of Central South University were recruited. The patients were divided into an experimental group and a control group based on whether bipolar coagulation forceps or sutures were used, respectively. RESULTS: The drainage output of the experimental group was significantly lower than that of the control group (p = 0.04). The duration of dressing pressure applied in the experimental group was significantly shorter than that in the control group (p = 0.0003). Moreover, the incidence of salivary fistula in the experimental group (9.8%, 8/82) was notably lower than that in the control group (34.7%, 33/95) (p < 0.0001). In the logistic regression model for salivary fistula development, both the use of bipolar coagulation forceps (p = 0.0021) and drainage output (p = 0.0237) were associated with the presence of salivary fistulas. CONCLUSIONS: Our findings indicate that the use of bipolar coagulation forceps decreases the incidence of salivary fistula in patients who have undergone a parotidectomy. The use of bipolar coagulation forceps is a safe, effective, and convenient method to prevent salivary fistulas in patients who undergo a parotidectomy. TRIAL REGISTRATION: Current Controlled Trials ChiCTR2100044722, Date: 26/03/2021, Retrospectively registered.

Superficial or partial superficial parotidectomy for the treatment of primary benign parotid tumors.

OBJECTIVE: The extent of surgery in benign superficial parotid tumors has no strong evidence-based consensus. Partial superficial parotidectomy (PSP) is a popular choice among surgeons. We retrospectively evaluated the hypothesis that it carries similar efficacy and greater safety than superficial parotidectomy (SP). PATIENTS AND METHODS: Between 2010 and 2016, 84 patients with benign superficial parotid tumors were enrolled in the study. Deep lobe and recurrent tumors were excluded. The patients were treated by SP; (40 patients) or PSP; (44 patients). The operative and postoperative morbidity, tumor recurrence, operative time, and length of hospitalization were analyzed. RESULTS: There was no significant difference regarding patients or tumors in baseline data. PSP showed significantly shorter operative time (P = .022), and hospital stay (P = .001), as well as significantly lower frequencies of postoperative transient facial nerve paralysis and Frey's syndrome, (P = .042 for each). Permanent facial dysfunction was nonsignificantly greater in SP. No tumor recurrence was detected in either group after a median follow-up of 7 years. CONCLUSIONS: PSP is a quicker and less extensive procedure. It was associated with a shorter hospital stay and fewer complications especially transient facial paralysis and Frey's syndrome with a recurrence rate comparable to that of SP.

Review of treatment modalities and outcomes of patients with basal cell adenocarcinoma.

PURPOSE: This study summarizes the treatment modalities of basal cell adenocarcinoma (BCAC) of the parotid gland and subsequent outcome at a single institution to better define the treatment of this rare tumor. MATERIAL AND METHODS: A retrospective review of patients treated for BCAC of the parotid gland from 1/01/1996 to 08/1/2018 was performed. Patients were identified using our institution's Cancer Registry. RESULTS: A total of thirteen patients (46% female, median age of 56) treated for BCAC of the parotid gland were identified. Eight patients (57%) were staged as T1, four were staged as T2 (29%), and two were stage T4a (14%) due to tumor involvement of the facial nerve. None of the patients had nodal involvement or distant metastases. Three patients (21%) underwent radiation therapy ranging from 60-70Gy for positive margin or facial nerve involvement by tumor. Five patients (36%) underwent a neck dissection (ND) ranging from just a level IIb dissection up to levels IIa, IIb, and III with none of the nodes being positive for disease. The remainder of patients did not undergo a neck dissection. Follow-up was 8.1 ± 6.2 (mean ± SD) years with no local or regional recurrence at time of last follow-up in any patient cohort. CONCLUSIONS: Our review suggests that elective neck dissections are not necessary following resection of T1/T2N0M0 basal cell adenocarcinoma for the prevention of local or regional recurrence. No longer performing neck dissections for T1/T2N0M0 BCAC would reduce the morbidity associated with the treatment of this rare parotid tumor.

Facelift Surgery Following Superficial Parotidectomy: Is it Safe?

INTRODUCTION: Patients who have previously undergone superficial parotidectomy may also seek facelift surgery for facial aging and rejuvenation. These patients present unique challenges compared to a standard facelift patient. Most concerning is the location of facial nerve branches, which may be superficial and displaced. In addition, significant contour deformities and abnormal scar patterns may be present. The purpose of the study is to review our series of patients and assess potential morbidity and safety of facelift surgery in superficial parotidectomy patients. METHODS: A retrospective case series was performed reviewing all patients who underwent facelift surgery following superficial parotidectomy from 2000 to 2017. Data were collected for: postoperative facial nerve deficit, soft tissue contour and scar deformities, facelift technique, ancillary soft tissue augmentation procedures and pre- and postoperative photographs. An evidence-based treatment algorithm to address specific problems in this patient population was developed. RESULTS: A total of seven patients were identified who underwent facelift surgery following parotidectomy. Patients underwent one of the standard SMAS procedure on the non-parotidectomy side, and surgical modifications were made to address the parotidectomy side; soft tissue augmentation was performed in two patients. Precautions to identify the facial nerve and prevent injury, including nerve monitoring and stimulation, were utilized in all seven patients. No permanent postoperative facial nerve injury was noted. CONCLUSION: Facelift following superficial parotidectomy was safely performed in all cases. Special consideration should be given to contour deformities, facial nerve location and scar placement. However, if approached properly, these patients can still be considered as suitable candidates for facelift surgery. LEVEL OF EVIDENCE IV: This journal requires that authors assign a level of evidence to each article. For a full description of these evidence-based medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266.

A multiparametric analysis based on DCE-MRI to improve the accuracy of parotid tumor discrimination.

BACKGROUND: Recently, semiquantitative time-intensity curve (TIC) analysis based on DCE-MRI and apparent diffusion coefficient (ADC) value-based diffusion-weighted imaging (DWI) were used to improve the diagnostic efficiency when diagnosing parotid tumors (PTs). However, quantitative DCE-MRI biomarkers have not been emphasized previously. PURPOSE: To explore the diagnostic efficiency of perfusion parameters alone or in combination based on quantitative DCE-MRI and DWI in the differential diagnosis of PTs. METHODS: In total, 112 patients with parotid masses were prospectively recruited in our hospital from August 2013 to March 2017. All patients were evaluated with DCE-MRI and DWI before surgery. TIC and quantitative parameters based on DCE MRI and ADCs were analyzed. Receiver operating characteristic analysis and linear discriminant analysis (LDA) was used to determine their diagnostic performance. RESULTS: In total, 87% (27/31) of pleomorphic adenoma (PA) showed type A TIC, 74% (65/88) of Warthin's tumors showed type B TIC, and 95% (19/20) of malignant tumors showed TIC type C. Pearson X2 test showed a significant difference between TIC patterns in benign and malignant tumors (X2 = 38.78, p < 0.001). ROC analysis revealed that ADC achieved the best diagnostic performance for distinguishing PA and Warthin's tumor from others, with area under the curve (AUC) values of 0.945 and 0.925 (p < 0.01), respectively. Furthermore, the TIC type was the only useful biomarker for distinguishing malignant from benign PTs, with an AUC of 0.846 (p < 0.01). Concerning the accuracy of the combined application of multiple parameters of DCE-MRI and ADC values, a combination of TIC pattern and extracellular volume ratio (Ve) provided the best results among five protocols, producing the highest accuracy of 0.75, followed by the combined use of the TIC pattern and ADC (accuracy was 0.70). CONCLUSION: TIC pattern in combination with the Ve biomarker based on DCE-MRI could achieve optimal diagnostic accuracy in the differential diagnosis of PTs.

Retrograde parotidectomy under local anesthesia for benign, malignant, and inflammatory lesions.

OBJECTIVE: To report the patient selection, surgical technique, and outcomes of parotidectomy using local anesthesia under monitored anesthesia care (MAC). METHODS: A retrospective chart review was performed for patients undergoing parotidectomy under local anesthesia at an academic head and neck surgery center. RESULTS: Six patients deemed high risk for general anesthesia (GA) due to medical comorbidities or with a strong preference to avoid GA underwent parotidectomy using local anesthesia and MAC. Parotidectomy was performed for several indications, including benign tumors, malignant tumors, and chronic sialadenitis. Mean age of patients was 78.0 ±â€¯7.9 years, and all had an American Society of Anesthesia score ≥ 2 and Charlson comorbidity index ≥4. Mean operative time was 102.8 ±â€¯38.3 min, comparable to that of parotidectomy under general anesthesia. No major complications occurred. Minor complications included three cases of temporary postoperative facial nerve weakness limited to 1-2 lower division branches. At most recent follow up (10 to 48 months), all patients were medically stable and disease free. CONCLUSION: In carefully selected patients, parotidectomy under local anesthesia is a viable treatment alternative that can be offered to patients. Successful outcomes require preoperative counseling, meticulous technique, and close collaboration with anesthesia colleagues.

A new method for tracing the facial nerve trunk using the posterior auricular nerve.

Tracing the facial nerve trunk is an essential action in parotid surgery, because of the implications of injury to the nerve or its branches. More than a few landmarks that may help the surgeon in this task have been proposed (e.g., the posterior belly of the digastric muscle, the tragal pointer, among others), under the assumption that additional access methods improve the surgical technique and reduce the possibility of harmful post-operative consequences. Here we present evidence that the posterior auricular nerve may be used to trace the facial nerve trunk. We dissected 75 cadaveric heminecks, exposed the auricularis posterior muscle and adnexa, and attempted to follow the posterior auricular nerve to the facial nerve trunk. The auricularis posterior muscle, nerve, and artery were identified in all heminecks, securing an anatomically reliable route to the facial nerve trunk. Average length of the nerve from the auricularis posterior muscle to the facial nerve trunk was 28 mm (±6.2 mm). The angle between the posterior auricular nerve and the vertical segment of the FN trunk was 39.5° (±7.7°). We conclude that the posterior auricular nerve may be used as a landmark to trace the facial nerve trunk. It is advantageous due to the relatively simple and consistent regional anatomy, and also because manipulation of this nerve does not present a risk given that the auricularis posterior muscle is vestigial. The proposed landmark is particularly important in revision surgery, where the pre-auricular anatomy may have been distorted and scarred by previous operations. Clin. Anat. 32:453-457, 2019. © 2019 Wiley Periodicals, Inc.

National trends in inpatient parotidectomy: A fourteen-year retrospective analysis.

PURPOSE: Operating room (OR) procedures represent one quarter of hospitalizations, yet OR-related stays account for nearly 50% of hospital costs. Understanding trends in inpatient parotidectomy, associated charges, and key outcomes including length of stay is imperative in the era of evolving health reform. MATERIALS AND METHODS: The Nationwide Inpatient Sample (NIS) was queried for patients who underwent inpatient parotidectomy (ICD9-CM procedure code 26.31 and 26.32) between 2001 and 2014. Patient demographics, co-morbidities, hospital characteristics and outcomes including length of stay (LOS) and hospital charges were assessed. RESULTS: A total of 66,914 parotidectomies were performed in the inpatient setting between 2001 and 2014. The volume of inpatient parotidectomy decreased steadily by 48% over the study period (7375 procedures in 2001 to 3530 procedures in 2014). Average LOS increased from 1.8 days in 2001 to 2.5 days in 2014. Total charges increased from $17,072 in 2001 to $55,929 in 2014. In 2014, the majority of inpatient parotidectomies were performed in a teaching hospital (87%) and among patients who were older than 65 years (48.1%). In 2001, only 35.4% of patients who underwent parotidectomy were older than age 65, and relatively fewer surgeries were performed at teaching hospitals (63.1%). CONCLUSIONS: Inpatient parotidectomy in the United States has evolved over the past fourteen years. Notable trends include a nearly 50% reduction of inpatient surgery, doubling in LOS, tripling of hospital charges and predominance of elderly patients with malignant disease. These results provide insight into inpatient parotid lesion management.

Management of the facial nerve in parotid cancer: preservation or resection and reconstruction.

PURPOSE: Management of the facial nerve is instrumental in the surgical treatment of parotid cancer. METHODS: A literature search was conducted using PubMed and ScienceDirect database. A total of 195 articles were finally included into the analysis, based on relevance, scientific evidence and actuality. RESULTS: In the majority of cases the facial nerve is not involved by tumor. In these cases, identification and preservation of the nerve, in addition to complete tumor removal, are essential for successful surgery. When the nerve is infiltrated by tumor, the affected portion of the nerve must be resected as part of radical parotidectomy. Primary nerve reconstruction or other reanimation techniques give the best long-term functional and cosmetic results. A comprehensive diagnostic evaluation with current imaging and electrophysiological studies will provide the surgeon with the best knowledge of the relationship of the facial nerve to the tumor. Several standardized methods are helpful in finding, dissecting and preserving the nerve during parotid cancer surgery. When radical parotidectomy is indicated, the initial diagnostic work-up can assist in defining the need for adjuvant postoperative therapy and facial reanimation. The aim of rehabilitation is to restore tone, symmetry, and movement to the paralyzed face. CONCLUSIONS: The surgical management of facial paralysis has undergone many improvements in recent years. This review gives an overview of recent advances in the diagnostic work-up, surgical techniques and any necessary rehabilitation of the facial nerve in parotid cancer surgery.