The extent of surgery for benign parotid pathology and its influence on complications: A prospective cohort analysis

Evaluation of the effectiveness of superficial parotidectomy and partial superficial parotidectomy for benign parotid tumours: a meta-analysis

OBJECTIVE

To quantify the results of superficial parotidectomy (SP) and partial SP (PSP) for benign parotid tumours using a systematic evaluation method.

METHODS

A systematic search of English and Chinese databases (PubMed, Web of Science, Cochrane Library, China Knowledge Network, Wanfang and Vipshop) was conducted to include studies comparing the treatment outcomes of SP with PSP.

RESULTS

Twenty-three qualified, high-quality studies involving 2844 patients were included in this study. The results of this study showed that compared to the SP surgical approach, the PSP surgical approach reduced the occurrence of temporary facial palsy (OR = 0.33; 95% confidence interval [CI] 0.26-0.41), permanent facial palsy (OR = 0.28; 95% CI 0.16-0.52) and Frey syndrome (OR = 0.36; 95% CI 0.23-0.56) in patients after surgery, and the surgery operative time was reduced by approximately 27.35 min (95% CI - 39.66, - 15.04). However, the effects of PSP versus SP on salivary fistula (OR = 0.70; 95% CI 0.40-1.24), sialocele (OR = 1.48; 95% CI 0.78-2.83), haematoma (OR = 0.34; 95% CI 0.11-1.01) and tumour recurrence rate (OR = 1.41; 95% CI 0.48-4.20) were not statistically significant.

CONCLUSION

Compared with SP, PSP has a lower postoperative complication rate and significantly shorter operative time, suggesting that it could be used as an alternative to SP in the treatment of benign parotid tumours with the right indications.

A retrospective study of parotid gland tumors at a single institution

The aim of the present study was to analyze the clinical characteristics, surgical treatments and clinical outcome of patients with parotid gland tumors and to compare the results with those cited in the literature. A retrospective study was conducted in 140 patients (male, n=77; female, n=63) with parotid gland tumors who underwent parotidectomy at Hokuto Hospital Department of Otolaryngology-Head and Neck Surgery (Obihiro, Japan) between April 2007 and December 2021. Of the 140 patients enrolled, 118 (84.3%) patients had benign tumors, including 63 (45%) patients with pleomorphic adenomas and 43 (30.7%) patients with Warthin tumors, and 22 patients (15.7%) had parotid carcinoma. Comparison of the three groups of patients with parotid gland tumors indicated that pack years as an indicator of smoking status were significantly higher in patients with Warthin tumors than in those with parotid carcinomas (P=0.011) or pleomorphic adenoma (P<0.001). Fine-needle aspiration cytology (FNAC) was non-diagnostic for only 6 (4.3%) of 140 patients. The sensitivity, specificity, positive predictive value, negative predictive value and accuracy of FNAC by both conventional smear and liquid-based cytology (LBC) for parotid carcinomas were 70, 99, 93.3, 94.4 and 82.9%, respectively. Among the 22 patients with parotid carcinoma, extended total/total and superficial parotidectomy were performed in 10 (45%) and 11 (50%) cases, respectively. Total and selective neck dissection of the area from level II to I, II and III were performed in 6 (24%) and 7 (32%) patients, respectively. Postoperative radiotherapy (50 Gy) was performed in 15 (68%) patients. The overall survival (OS) and disease-free survival (DFS) rates at 5 years were 51.5 and 76.4%, respectively. Univariate analysis revealed that age >65 years was significantly associated with poorer 5-year OS (P<0.001) and DFS (P<0.001). Multivariate analysis revealed that an age of more than 65 years combined with high-grade histologic malignancy was associated with worse DFS (P=0.02; hazard ratio, 3.628; 95% confidence interval, 1.283-9.514). In conclusion, the clinical characteristics and treatment outcomes of parotid gland tumors were consistent with the results of previous reports. Smoking may be closely related to the pathogenesis of Warthin tumors. LBC potentially provides improved accuracy in FNAC.

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.

Comparing postoperative outcomes using electrocautery versus cold-knife de-epithelialization of dermal fat graft in parotidectomy reconstruction

PURPOSE

The present study was developed to evaluate the effectiveness of a simple rapid technique for de-epithelializing cutaneous flaps and grafts in parotidectomy reconstruction.

MATERIALS AND METHODS

109 patients who underwent a parotidectomy with abdominal free dermal fat graft (FDFG) reconstruction between 2018 and 2021 were evaluated based on demographic factors, past medical/surgical history, type of parotidectomy performed, operative factors, and post-operative complications. These data were then stratified based on de-epithelialization technique as well as tumor malignancy status to determine any differences in complication rates or perioperative factors between electrocautery (EC) and cold knife (CK) techniques within both benign and malignant subgroups.

RESULTS

77 of the 109 participants underwent FDFG de-epithelialization using monopolar electrocautery (EC) and the remaining 32 participants underwent de-epithelialization using traditional cold knife (CK) technique. There was no statistical difference among the two groups in overall complication rate. The EC group had a significantly shorter operation time ("EC vs. CK": 144.2 min vs. 174.7 min; p = 0.031). Additionally, histopathologic samples showed that both techniques left the underlying dermis intact and without damage.

CONCLUSIONS

This study demonstrated that there is no difference in complication rate or histology of FDFGs de-epithelialized using EC compared to CK. It was also shown that when controlling for confounders by looking solely at the benign subgroup of patients, EC de-epithelialization was a faster technique than CK. These findings suggest that EC is just as effective as CK, and may actually be a more efficient surgical technique to accomplish de-epithelialization of FDFG.

Effectiveness of the Fibrinogen-Thrombin-Impregnated Collagen Patch in the Prevention of Postoperative Complications after Parotidectomy: A Single-Blinded, Randomized Controlled Study

We investigated whether a fibrinogen-thrombin collagen sponge patch reduces postoperative complications of parotid gland surgery. This single-blinded, randomized controlled study included 165 patients who underwent parotid surgery for benign tumors (2018–2019) at a tertiary center. Primary outcomes were postoperative drain amount, days until drain removal, and discharge. Patients were scheduled for follow-up at 1 and 4 weeks, and 3 months after surgery. Complications including surgical site infection, pain, seroma, sialocele, salivary fistula, facial nerve palsy, Frey’s syndrome with subjective symptoms, and facial asymmetry were analyzed. After identifying confounding variables, multivariate approaches were used. Histologic analysis was performed in a mouse model of salivary gland surgery. In total, 162 patients (77, fibrinogen-thrombin collagen patch group; 85, controls) were included, with no significant between-group differences other than resected tissue. Among postoperative total drain amount and days until drain removal and discharge, the only postoperative total drain was significantly lower in the patch group than in the control group in the adjusted model. Additionally, although validation through robust trials with longer follow-up is needed, we found the potential benefit of the fibrinogen patch on Frey’s syndrome and facial asymmetry. In conclusion, fibrinogen-thrombin-impregnated collagen patches in parotidectomy can reduce postoperative drainage and improve outcomes.

Postparotidectomy sialocele: A 6-year review of underlying factors

BACKGROUND

Postparotidectomy sialocele is a frustrating challenge. Published rates of postparotidectomy fluid collections range from 6% to 39%. We report our experience of 398 parotidectomies performed over a 6-year period.

METHODS

A retrospective chart review of parotidectomies performed over a 6-year period was completed. Drain placement, smoking status, tumor size, and postoperative utilization of scopolamine were analyzed. Binary logistical regression and odds ratio calculations were performed.

RESULTS

Postparotidectomy sialocele occurred in 25% of patients. Neither suction drain placement nor usage of immediate postoperative scopolamine (in a 22-patient subset) prevented sialocele formation. Smoking status also did not correlate. Increasing resection size was linearly correlated with the risk of sialocele.

CONCLUSION

Drain placement and smoking status do not correlate with sialocele prevention after parotidectomy. Sialocele formation directly correlates with the resection size. These data may guide preoperative counseling; however, additional work is necessary to identify effective prevention mechanisms for postparotidectomy sialocele.

The importance of the patient's perspective in function-sparing parotid surgery for benign neoplasms: clinical reappraisal

Objective

Function-sparing surgery is the cornerstone for the treatment of benign parotid neoplasms. We assessed the incidences and determinants of the main postoperative complications, reappraising their influence on the patient’s quality of life (QoL).

Methods

Patients who underwent parotid surgery for benign neoplasms were reviewed (2016-2019). Parotidectomy Outcome Inventory-8 (POI-8) and condition-specific questionnaires were used to investigate the patient’s perspective.

Results

We enrolled 211 patients. Preservation of the posterior branch of the great auricular nerve (GAN) seemed to reduce early dysfunction (87% vs 96%, p = 0.053), but not the late one. Deep lobe dissection and resection of more than one parotid segment favoured first bite syndrome (FBS) and Frey’s syndrome (FS), respectively (16% vs 3%, p = 0.003; 37% vs 15%, p = 0.003). Neither GAN impairment, FBS, nor FS influenced patient QoL. Facial weakness affected 19 patients (9%), being more likely after total parotidectomy (23% vs 7%, p = 0.034). According to POI-8, QoL was mainly jeopardised by fear of revision surgery, especially in females (p= 0.005) and those experiencing early complications (p= 0.004).

Conclusions

Reappraisal of the patient’s perspective after functional parotid surgery is fundamental to tailor preoperative counselling.

Feasibility of using the postauricular-groove approach without endoscopic assistant for excision of parotid tumors. Results from a series of 58 cases

The aim of the study was to evaluate the efficacy and preliminary outcomes of using a postauricular-groove approach without endoscopic assistance for the excision of parotid tumors. Patients who underwent parotidectomy using a postauricular-groove incision were selected for this study. For patients in which parotidectomy was difficult, namely, for tumors located in the deep lobe area, the parotid gland sternocleidomastoid space was fully utilized, and the tumor was resected from the posterior plane. A total of fifty-eight patients with parotid tumor were enrolled and divided into superior lobe group (n = 46) and deep lobe group (n = 12). The difference in operation time (94 vs 119 min) and postoperative drainage (20.18 vs 45.33 mL) was statistically significant between the tumors in the superficial and deep lobes. However, postoperative cosmetic VAS score was 10 (extremely satisfied) for all patients. The incidence of transient facial nerve paralysis was comparable (8.7% vs 16.7%), and all of them resolved spontaneously within 3 months. No recurrence of tumors was found in either group in the median follow-up interval of 26.45 months (range 22.2-35.3 months), which was comparable to the result using the conventional "S" approach. After making full use of the parotid gland sternocleidomastoid space, the postauricular-groove approach demonstrated satisfactory facial nerve protection, as well as easy maneuverability without the risk of surgical complications for tumors located in the deep lobe area. Importantly, the postauricular-groove approach showed excellent cosmetic outcomes for all patients and should be considered an alternative approach for parotidectomy of selected cases.

Predictors of Sialocele or Salivary Fistula After Partial Superficial Parotidectomy for Benign Parotid Tumor: A Retrospective Study

PURPOSE

Partial superficial parotid (PSP) resection is the mainstay of treatment for benign parotid tumor. Unfortunately, the post-surgical formation of sialocele or salivary fistula is a well-recognized complication of parotid surgery. The aim of this study was to determine the predictors of sialocele or salivary fistula after PSP resection for parotid benign tumor.

METHODS

This retrospective cohort study includes patients who underwent PSP resection for benign parotid tumors from January 1, 2015 to December 31, 2019. The predictor variables were demographic data, systemic disease, smoking history, tumor size and type, surgical approach, and area. The outcome variables were the occurrence of sialocele or salivary fistula after PSP resection. Each possible risk factor was then examined using univariate analysis. Variables associated with sialocele or salivary fistula in the univariate analysis were then included in a multiple logistic regression model, and analyzed for possible factors related to the occurrence of sialocele or salivary fistula after partial superficial parotid resection.

RESULTS

The sample was composed of 872 subjects with a mean age of 51.0 ± 8.3, and 59.5% were male. The frequency of sialocele or salivary fistula after partial superficial parotid resection was 10.4% (n = 92). Based on the multiple logistic regression model, hypertension and location of the lesion were associated with sialocoele formation. Hypertension was associated with a decreased risk for the formation of sialocele or salivary fistula (ORs = 0.6, 95% CI = [0.4,1.003], P = .051). When compared the superior lesions, anterior lesions were associated with a decreased risk for the formation of sialocele or salivary fistula (ORs = 0.32, 95% CI = [0.111,0.92], P = .034) and lesions in the middle were associated with an increased risk for sialocele or salivary fistula development (ORs = 2.315,95% CI = [1.199,4.469], P = .012).

CONCLUSIONS

The incidence of sialocele or salivary fistula development was 10.4% in patients undergoing partial superficial parotidectomy in this study. Moreover, middle and anterior tumor location was shown to increase sialocele or salivary fistula risk.

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.

Surgical management and outcomes of accessory parotid gland neoplasms: A systematic review

OBJECTIVE

To evaluate surgical approaches and outcomes associated with accessory parotid gland neoplasms.

DATA SOURCES

MEDLINE, SCOPUS, and the Cochrane Central Register of Controlled Trials.

REVIEW METHODS

A systematic review in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) was performed. Studies were included if they reported surgical management and outcomes of patients with accessory parotid gland neoplasms.

RESULTS

After screening 3532 records, 15 studies were included with a total of 187 patients. Benign tumors consisted of 61.5% of cases. External open, transoral, and preauricular endoscopic approaches were used for 82.3%, 11.3%, and 6.5% of cases, respectively. Accessory lobe resection alone, concurrent with partial parotidectomy, and concurrent with total parotidectomy were used in 54.8%, 43.0%, and 2.2% of cases, respectively. Complication rates were similar between histology groups (7.8% benign vs. 8.3% malignant, p = 0.82). Accessory lobe resection with concurrent partial parotidectomy had the lowest overall complication rate (6.3%). Resections limited to the accessory lobe were found to have an overall complication rate of 8.7%.

CONCLUSION

The results offer an overview of the surgical management and complications for accessory parotid gland tumors. Overall surgical complication rates found in these case series may be lower for management of accessory gland tumors than rates available in the literature for tumors within the main parotid gland.

Comparison of postoperative complications and facial nerve recovery rates after conventional and partial superficial parotidectomy of benign parotid tumours: a prospective study

The aim of this study was to compare postoperative complications and facial nerve (FN) recovery rates between conventional superficial parotidectomy (CSP) and partial superficial parotidectomy (PSP) as surgical treatment for benign parotid tumours. A prospective study was conducted on 55 consecutive patients who underwent either CSP (n=35) or PSP (n=20) for benign parotid tumours. The primary outcomes were FN injury, FN recovery rates, and Frey syndrome. Secondary outcomes were operative time, hospital stay, sialocele, haematoma, and auricular numbness. The degree of FN injury was evaluated at 1 week, 1, 3, 6, and 12 months postoperative using the House-Brackmann grading system. Frey syndrome was assessed using a subjective clinical questionnaire and objective Minor starch-iodine test. No patient in either group experienced permanent FN paralysis. There was a significantly higher incidence of temporary FN weakness in the CSP group (P=0.007). The respective FN recovery rates at 1, 3, 6, and 12 months were 60%, 88.6%, 94.3%, and 100% in the CSP group and 90%, 95%, 100%, and 100% in the PSP group. No significant difference was observed between the groups regarding the incidence of Frey syndrome, sialocele, and haematoma. The operative time and hospital stay were both shorter in the PSP group. Although the PSP is a more conservative procedure with significantly reduced FN injury, operative time, and hospital stay compared to CSP, the CSP procedure shows a comparable FN recovery rate to the PSP.

Minor Parotidectomy Complications: A Systematic Review

OBJECTIVES

To report descriptive statistics for minor parotidectomy complications.

METHODS

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

RESULTS

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

CONCLUSIONS

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

Differentiation of salivary gland tumors through tumor heterogeneity: a comparison between pleomorphic adenoma and Warthin tumor using CT texture analysis

PURPOSE

We compared the diagnostic performance of CT texture analysis in single-phase CT scan with that of conventional enhancement pattern analysis in a two-phase CT scan for discrimination of salivary gland tumors, Warthin tumor (WT) from pleomorphic adenoma (PA).

METHODS

One hundred seventy-eight patients with PA and 84 patients with WT were selected and CT texture analysis was separately performed on early (40s) and delayed (180s) phases, after injection of the contrast agent, using commercially available software. The attenuation changes and enhancement patterns were visually and quantitatively assessed with Hounsfield units (HU). Differences between PAs and WTs were analyzed using χ² test and independent t test. Diagnostic performance of texture parameters in single-phase CT was compared with that of dynamic enhancement pattern in two-phase CT using the McNemar test.

RESULTS

Ratio of tumoral HU (delayed phase/early phase) was significantly higher in PAs compared with WTs (p < 0.001). Tumor heterogeneity parameters, standard deviation (SD) and entropy, were significantly lower in WTs regardless of the type of filter used (p ≤ 0.001). Mean with coarse filter (AUC = 0.944) on early phase scan and entropy with medium filter (AUC = 0.901) on delayed scan were best discriminators between PAs and WTs. Diagnostic accuracy of mean (90.5%) on early scan and entropy (84.7%) on delayed scan was not significantly different from the accuracy (89.3%) of conventional wash-out pattern for distinguishing WTs from PAs (p = 0.742, p = 0.088, respectively).

CONCLUSION

Diagnostic performance of texture parameters was similar to that of quantitative enhancement pattern for differentiating WTs from PAs, with the advantage in lower radiation exposure.

Outpatient versus Inpatient Parotidectomy: A Systematic Review and Meta-analysis

OBJECTIVE

Parotidectomies are commonly performed procedures by head and neck surgeons. Although parotidectomies are historically inpatient procedures, recent observational evidence has highlighted the potential for parotidectomies to be performed on an outpatient basis. This systematic review and meta-analysis sought to compare complications and unplanned health care utilization between patients undergoing outpatient versus inpatient parotidectomy.

DATA SOURCES

A systematic review was performed using MEDLINE, EMBASE, and the Cochrane Library.

REVIEW METHODS

Studies comparing the outcomes of outpatient parotidectomy with those of inpatient parotidectomy were included. Risk of bias was assessed using the Newcastle-Ottawa Scale. Postoperative complications (hematoma, facial nerve dysfunction, seroma, fistulisation, Frey syndrome, and wound infection) and rates of 30-day readmission, reintervention, and emergency department presentation were compared.

RESULTS

We screened 1018 nonduplicate articles to include 5 studies, all of which were retrospective cohort studies. There were fewer complications found in the outpatient group (relative risk = 0.61, 95% confidence interval: 0.40-0.93). Outpatient procedures were more commonly performed on patients who lived close to the hospital, had fewer comorbidities, and had less extensive planned surgery.

CONCLUSION

Outpatient parotidectomy appears safe in select patients with outcomes comparable with inpatient surgery. However, evidence overall is of low quality, and further work is needed to delineate a satisfactory set of criteria for appropriate patient identification.

Post parotidectomy facial nerve palsy: A retrospective analysis

Background &Objectives:

Transient paralysis of facial nerve is seen to vary from 15 % to 66 % in post-parotid surgery. The objective of this study was to find out the complications in post-parotidectomy with regards to facial nerve dysfunction since it is a vital structure encountered in parotid surgeries.

Methods:

This was a retrospective study through non probability convenient sampling technique carried from September 2010 to January 2019 in the Department of Otorhinolaryngology, Dow University of Health Sciences, Dr. Ruth K.M.Pfau Civil Hospital, Karachi. Clinical data were recorded from 75 patients and out of them 70 patients had undergone surgery with parotid gland tumours and were reported on the morphology, age, sex, surgical procedure and complications, particularly facial nerve dysfunctions. In most cases ante-grade technique was performed to identify the facial nerve, whereas retrograde technique was used in recurring tumours, and in difficult cases. The stimulator of the nerve has not been used. The nature or severity of Facial nerve dysfunction was assessed in terms of either it is, permanent or temporary, total or incomplete in respect to its branches.

Results:

Among total 75 patients; the mean age was 38.75 ± 9.26 years with male to female ratio of 1:1. Majority of the patients were diagnosed as pleomorphic adenoma, i.e. 78.6% after which 12% were diagnosed as mucoepidermoid carcinoma. 88.6% of patients had superficial parotidectomy and 11.4% of patients had total parotidectomy. About 75% of patients had no complications. 5(7.1%) patients had complete facial nerve palsy. Damage to the mandibular, buccal and temporozygomatic branch was observed in 10(14%), 2(3%) and 1(1.4%) patients respectively.

Conclusion:

The most prevalent benign parotid tumour in this study was pleomorphic adenoma. After performing parotid surgery, it was predicted that the rate of complications related to the facial nerve injury was reduced as compared to the previous studies.

Feasibility of ovine and porcine models for simulation training in parotid surgery and facial nerve dissection

PURPOSE

To assess and compare the feasibility of using ovine and porcine models as surgical simulation training tools for otolaryngology trainees performing parotid surgery and facial nerve dissection.

METHODS

Trainees performed parotid surgery (total parotidectomy, retrograde facial nerve dissection and facial nerve grafting) on an ovine and porcine model. Participants completed a 22-item, five-point Likert scale questionnaire on each model, assessing three validation domains; face validity (FV), global content validity (GCV) and task-specific content validity (TSCV). Data were prospectively collected and analysed using descriptive and non-parametric statistics.

RESULTS

Twelve trainees completed two consecutive parotidectomies and facial nerve dissections on an ovine and porcine model. Twenty-four dissections were completed. Validation questionnaires were completed for each model by all trainees. The ovine model achieved median validation threshold scores (≥ 4/5) for all aspects of FV, GCV and TSCV. The porcine model did not achieve validation threshold scores for any aspect of the validation questionnaire. Comparison of the ovine and porcine model demonstrated that the ovine model was statistically superior to the porcine model across most validation criteria excluding realistic appearance of skin, identification and ligation of the trans-oral parotid duct and facial nerve grafting.

CONCLUSION

Adequate experience with facial nerve dissection during parotid surgery is vital to ensuring good outcomes and avoiding complications. This study is the first to compare validity of two animal models for simulation training in parotid surgery and facial nerve dissection. We have validated the ovine model as a useful tool for simulation training and advocate its incorporation into otolaryngology training programmes.

Extracapsular dissection versus partial superficial parotidectomy for the treatment of benign parotid tumours

The purpose of this study was to compare the complications of patients treated for a benign parotid tumour (BPT) by extracapsular dissection (ECD) vs. partial superficial parotidectomy (PSP). A comprehensive literature investigation was conducted by searching electronic databases. A systematic review and meta-analysis of comparative studies were performed to assess ECD and PSP for the treatment of BPTs with fixed-effects models. The outcomes analysed were transient or permanent facial nerve injury, Frey syndrome, recurrence rate, infection, and salivary fistula/sialocele. A total of 1641 patients from seven studies (1120 ECD-treated and 521 PSP-treated patients) were included in this meta-analysis. Transient facial nerve injury (odds ratio (OR)=0.28, 95% confidence interval (CI): 0.11-0.71; p=0.008) and Frey syndrome (OR=0.12, 95% CI: 0.03-0.48; p=0.003) were less prevalent in the ECD group. The rates of permanent facial nerve injury (OR=0.77, 95% CI: 0.35-1.70; p=0.520), recurrence rate (OR=0.17, 95% CI: 0.02-1.75; p=0.14), infection (OR=0.70, 95% CI: 0.07-6.67; p=0.76), and salivary fistula/sialocele (OR=0.40, 95% CI: 0.06-2.66; p=0.350) were similar in both groups. Although there was a trend that ECD showed a reduced risk for complications, the present results are not sufficient to conclude that ECD is more beneficial than PSP.

Contemporary Management of Benign and Malignant Parotid Tumors

To report the standard of care, interesting new findings and controversies about the treatment of parotid tumors. Relevant and actual studies were searched in PubMed and reviewed for diagnostics, treatment and outcome of both benign and malignant tumors. Prospective trials are lacking due to rarity of the disease and high variety of tumor subtypes. The establishment of reliable non-invasive diagnostics tools for the differentiation between benign and malignant tumors is desirable. Prospective studies clarifying the association between different surgical techniques for benign parotid tumors and morbidity are needed. The role of adjuvant or definitive radiotherapy in securing loco-regional control and improving survival in malignant disease is established. Prospective clinical trials addressing the role of chemotherapy/molecular targeted therapy for parotid cancer are needed. An international consensus on the classification of parotid surgery techniques would facilitate the comparison of different trials. Such efforts should lead into a clinical guideline.