Water-jet dissection in parotid surgery: an experimental study in dogs

OBJECTIVE: The objective of the present study was to investigate the application of the water-jet dissection method in parotid surgery by way of animal experiments, paying particular attention to the clinical and histological reactions of the facial nerve. STUDY DESIGN: An animal experimental study. METHODS: Total bilateral parotidectomies with retention of the facial nerve were performed on 19 beagle dogs by means of the Hydro-Jet device (Andreas Pein Medizintechnik Company, Schwerin, Germany) using different jet diameters and operating pressures. All operations were performed with continuous intraoperative facial monitoring (Neurosign 100, Inomed Company, Teningen, Germany). The dogs were monitored postoperatively over an average period of 20.3 days (range, 14-35 d). Local findings and facial nerve status were documented daily. In a second phase, the dissected nerves were resected and the animals were killed. Samples of water-jet-dissected parotid tissue, as well as all dissected nerve branches, underwent histological examination and were compared with clinical and electrophysiological findings. RESULTS: It was possible to perform operations easily on all parotid glands by means of the Hydro-Jet using the small, 120-microm jet at operating pressures of 40 to 60 bar and to dissect the facial nerve quickly and safely with retention of its functional capability (n = 34). The dissection of nerves using larger-diameter jets (150 and 200 microm [n = 64]) resulted in a total of two reversible and seven irreversible partial pareses. CONCLUSIONS: The study has shown that it is possible to perform tissue-selective operations on the parotid gland by means of the Hydro-Jet using the 120-microm jet at operating pressures of 40 to 60 bar, ensuring safe, atraumatic dissection of the facial nerve with retention of its functional capability. The advantages of the new Hydro-Jet method offer a valuable alternative compared with the normal dissection methods adopted in parotid surgery. Thus the results of the present investigation currently are being checked within the framework of a clinical study at our clinic.     

Preliminary results for superficial parotidectomy using the ultrasonically activated scalpel (Ultracision Harmonic Scalpel)

BACKGROUND: The high density of blood vessels in the parotid gland, the direct vicinity to the facial nerve and the narrow surgical situs require efficient intra- and postoperative hemostasis. The ultrasonic scalpel (US) accomplishes both tissue dissection and vessel coagulation simultaneously by an ultrasonically activated shear movement of 55 500 Hz. The combination of hemostasis and tissue dissection particularly qualifies US for use in surgery of the parotid gland. Until now, there have been no published studies about application of US in surgery of the parotid gland. METHOD: 20 patients with benign parotid tumors treated with a conventional technique of superficial parotidectomy and 20 patients with a superficial parotidectomy using the ultrasonically activated scalpel were examined in regard to intra- and postoperative hemostasis, wound healing and postoperative pain. Also, the quality of the histopathological specimen obtained by US was evaluated. RESULTS: In 85 % (17/20) of superficial parotidectomy efficient intraoperative hemostasis did not require electrocoagulation. In 15 % (3/20) of parotid tumors additional bipolar electrocoagulation were required because of venous bleeding from vessels exceeding 2.0 mm in diameter. Postoperative bleeding did not occur at all. Wound healing was uneventful in all cases. Surgery-related postoperative pain was not intensified. Time of operation was shortened. Histopathological evaluation, especially in the margin area, was not impaired. CONCLUSION: The US offers tissue dissection with effective intra- and postoperative hemostasis. The combination of simultaneous tissue dissection and hemostasis enables a good overall view and control of the surgical site. In addition, based on the mechanical function the US has only a minimal thermal effect on neighboring tissues and enables controlled tumor resection without damaging the facial nerve.     

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

Background

The surgical management of benign parotid tumors is aimed at complete extirpation of the mass with preservation of facial nerve function. There is a relative paucity of literature pertaining to complications after benign parotid surgery and related risk factors. We aim to critically review the outcomes following treatment of benign parotid pathology when surgery entailed either complete superficial parotidectomy (CSP), partial superficial parotidectomy (PSP) or extracapsular dissection (ECD).

Continuous intraoperative facial nerve monitoring in predicting postoperative injury during parotidectomy

OBJECTIVES/HYPOTHESIS: To assess whether the use of continuous intraoperative facial nerve monitoring correlates to postoperative facial nerve injury during parotidectomy. STUDY DESIGN: A retrospective analysis. METHODS: Forty-five consecutive parotidectomies were performed using an electromyograph (EMG)-based intraoperative facial nerve monitor. Of those, 37 had complete data for analysis. Intraoperative findings and final interpretation of the EMGs were analyzed by a senior neurologist and neurophysiologist. All patients were analyzed, including those with preoperative weakness and facial nerve sacrifice. RESULTS: The overall incidence of facial paralysis (House-Brackmann scale > 1) was 43% for temporary and 22% for permanent deficits. This includes an 11% incidence of preoperative weakness and 14% with intraoperative sacrifice. An abnormal EMG occurred in only 16% of cases and was not significantly associated with permanent or temporary facial nerve paralysis (chi, P < 1.0; Fisher's exact P < .68). Of the eight patients with permanent paralysis, only two had abnormalities on the facial nerve monitor. Also, only one of five patients with intraoperative sacrifice of the facial nerve had an abnormal EMG. Factors significantly associated with the incidence of facial paralysis include malignancy, advanced age, extent of parotidectomy, and dissection beyond the parotid gland (chi and Fisher's, P < .05). CONCLUSIONS: The results suggest that abnormalities on the intraoperative continuous facial nerve monitor during parotidectomy do not predict facial nerve injury. The incidence of permanent and temporary facial nerve paralysis compare favorably with the literature given that this study includes patients with revision surgery, intraoperative sacrifice, and preoperative paralysis. Standard of care implications will be discussed.     

Intra-vital staining as an aid to parotid gland surgery.

Successful parotid surgery depends on the careful identification and dissection of the facial nerve, and to prevent recurrence all tumours should be excised with a wide margin of normal tissue. These two requirements are facilitated by the technique of intra-vital staining of the parotid gland with 2.5% methylene blue solution.     

Extra-temporal localized facial neuromas

Nine facial nerve schwannomas were observed in more than 1,350 operations on the parotid gland. Eight patients had a pre-operative diagnosis of pleomorphic adenoma without facial palsy. One patient who underwent extensive surgery without preservation of the facial nerve for a tumour present for more than 10 years had a pre-operative facial palsy. Facial nerve function recovered totally or partially in six peripheral schwannomas. In two cases with main trunk schwannoma no reinnervation was observed despite end-to-end anastomosis or interposition of the great auricular nerve. Histology showed eight typical schwannomas and one neurofibroma. Neurofibromas are extremely rare in the parotid gland. Clinical and operative experience with parotid gland schwannomas shows that recovery of facial nerve defects is mostly incomplete. Reconstructive methods should be used, but the long-term prognosis is uncertain.     

Facial nerve morbidity following parotid surgery for benign disease: The cleveland clinic foundation experience

Standard surgical management for benign tumors of the parotid gland requires either superficial, subtotal, or total parotidectomy with preservation of the facial nerve. Although this approach is effective in minimizing recurrence, the resultant facial nerve morbidity is seldom addressed. Two hundred fifty-six consecutive patients who underwent parotid surgery for benign neoplasia at this institution in the past 15 years are reviewed, with attention to postoperative facial nerve function. Immediate dysfunction was frequently encountered (46.1%), but permanent dysfunction was uncommon (3.9%). The incidence of long-term dysfunction may be higher in revision cases and when an extended (total or subtotal) parotidectomy is performed.     

Results of the surgical management and histopathological evaluation of 88 parotid gland Warthin’s tumours

With the introduction of parotidectomy after identification of the facial nerve the recurrence rates for benign tumours has declined rapidly. Subsequently, attention was focused on other sequelae of parotid surgery. To reduce the specific surgical morbidity, several modifications of parotidectomy have been implemented. This study compares the results of the different surgical techniques with regard to the histopathological findings and recurrence rate for Warthin’s tumour of the parotid gland. Eighty-eight primary surgical parotid procedures were performed on 85 patients for a Warthin’s tumour. The surgical procedures included 52 ‘partial’ superficial parotidectomies, 22 ‘standard’ superficial parotidectomies, 12 partial superficial/deep lobe parotidectomies, and two ‘selective’ deep lobe parotidectomies. No patient developed a recurrence or experienced permanent facial nerve paresis/paralysis, the median follow-up being 93 months. Histopathological examination revealed a multifocal origin in 23% (20/88) of the surgical specimens. Partial parotidectomy is an effective treatment for Warthin’s tumour. There is no need for extended follow-up.     

Safety and usefulness of an electric knife during surgery for parotid benign tumor: postoperative facial paresis and its risk factors

CONCLUSION: The incidence of facial nerve paresis was not high compared with previously reported incidences using conventional operative techniques, showing the safety of the use of an electric knife in this operative technique. An electric knife is provided in almost all operating rooms and no special apparatus is necessary for this technique. BACKGROUND: Since the glandular tissue of the parotid gland is rich in blood flow, safe and accurate protection of the nerve is often made difficult due to bleeding during parotid surgery. Therefore, we developed a technique in which glandular tissue is cut using an electric knife, which is provided in almost all operating rooms. PATIENTS AND METHODS: In this study, the safety and usefulness of an electric knife in parotid surgery were confirmed by evaluating patients with parotid benign tumor who underwent surgery using an electric knife. The subjects were 135 patients with parotid benign tumors. RESULTS: Postoperative facial nerve paresis developed in 36 (26.6%) of the 135 patients but was transient in all cases. Depending on the tumor site, transient paresis was observed in 8 of the 13 patients with tumors in the deep lobe but in 28 (22.9%) of the 122 patients with tumors in the superficial lobe. The mean recovery time from facial nerve paresis was 6.1 weeks.     

Monitorización intraoperatoria del nervio facial durante la cirugía de la glándula parótida en servicios de otorrinolaringología - cirugía de cabeza y cuello

IntroductionFacial nerve injury remains the most severe complication of parotid gland surgery. Due to the increasing evidence about the advantage of the use of intraoperative facial nerve monitoring, a survey was distributed among members of the Spanish Society of Otorhinolaryngology-Head and Neck Surgery with the objective of determining patterns of its use.Material and methodsA questionnaire which included 12 separate questions in 3 sections was distributed via email through the official email of the Spanish Society of Otorhinolaryngology-Head and Neck Surgery. The first section of questions was in relation to demographic characteristics, the second section was related to the pattern of monitoring use and the third section referred to litigation related to facial palsy.Results1544 anonymous questionnaires were emailed. 255 surveys were returned, giving an overall response rate of 16.5%. From these, 233 (91.3%) respondents perform parotid gland surgery. Two-hundred nineteen (94%) respondents use intraoperative facial nerve monitoring. Of the respondents,94% used intraoperative facial nerve monitoring if in their current practice they performed fewer than 10 parotidectomies per year and 93.8% if they performed more than 10 (OR, 1.02; 95% CI, 0.68-1.45; p = .991). With regard to lawsuits, just 3 (1.2%) of the respondents had a history of a parotid gland surgery–associated lawsuit and in just one case the facial nerve monitor was not used.ConclusionOur data demonstrate that most otolaryngologists in Spain use intraoperative facial nerve monitoring during parotid gland surgery. Almost all of them use it to improve patient safety and consider that facial nerve monitoring should be helpful preventing inadvertent injury.     

Facial nerve dysfunction after parotidectomy: the role of local factors

OBJECTIVES/HYPOTHESIS: The objective was to analyze the incidence and factors associated with facial nerve dysfunction after conservative parotidectomy with facial nerve dissection. STUDY DESIGN: A retrospective unicentric study in a tertiary care center with prospective record of studied factors. METHODS: Over a 10-year period, 131 patients with normal facial nerve function underwent a superficial or total conservative parotidectomy with nerve dissection performed by one surgeon for primary benign or malignant tumors. Facial nerve function was assessed on the first postoperative day and at 1 month and 6 months after the parotidectomy. Extent of surgery, histopathological findings, tumor size, close contact of tumor with facial nerve, and sex and age of the patient were reviewed. These variables were studied in a chi2 statistical univariate and stratified analysis to determine their association with postoperative facial nerve dysfunction. RESULTS: Incidence of postoperative facial nerve dysfunction was 42.7% on the first postoperative day, 30.7% at 1 month after the parotidectomy, and 0% at 6 months after the parotidectomy. The most common dysfunction was paresis in a single nerve branch (48.2%), in particular, the marginal mandibular branch. Total parotidectomy was associated with a significantly higher incidence of facial nerve dysfunction during the first postoperative period (60.5% at day 1 and 44.7% at month 1) than superficial parotidectomy (18.2% at day 1 and 10.9% at month 1) (P < .001). In patients with total parotidectomy, close contact of the tumor with the facial nerve was found to have statistical causal relation with facial nerve weakness. In patients with superficial parotidectomy, inflammatory conditions were found as factors that increased postoperative facial nerve dysfunction. CONCLUSION: In the study series of conservative parotidectomies with facial nerve dissection, only extent of surgery and particular local conditions of nerve dissection, especially the close contact of tumor with facial nerve and inflammatory conditions, were found to be associated with postoperative facial nerve dysfunction.     

腮腺复发性肿瘤的手术方式及临床观察

目的探讨腮腺复发性肿瘤的病理类型、再次手术的方式及术后并发症。方法对2015~2018年我科腮腺复发性肿瘤14例患者的再次手术方式及并发症进行回顾性分析,追踪临床随访情况。结果14例患者术后复发时间半年到30年不等,7例为多形性腺瘤,其中1例恶变,其余病理包括血管性疾病、腺淋巴瘤、囊肿、木村病、腺癌等;12例为第2次手术,2例为第3次手术;10例患者行腮腺浅叶切除,4例患者行全腮腺切除,3例行放疗治疗;主要并发症为暂时性面瘫7例,持续性面瘫2例,涎瘘2例,Frey综合征1例。1例行3次手术患者复发肿瘤瘢痕组织与面神经分界不清,予以保留面神经,术后病理证实切缘为瘢痕纤维组织,未见肿瘤细胞。随访期间所有病例未见肿瘤复发。结论腮腺复发性肿瘤以多形性腺瘤最常见,再次手术建议采用浅叶或全腮腺切除,避免区域性切除,减少复发。多次手术解剖困难,神经损伤几率增加,术中可使用神经监护仪,利于神经保护。     

Carcinosarcoma of the parotid gland: report of a case with immunohistochemical findings

OBJECTIVES: Carcinosarcoma (true malignant mixed tumor) of the parotid gland is an extremely uncommon tumor composed of both carcinomatous and sarcomatous components. An understanding of this manifestation is crucial to guide management and treatment of this disease. METHODS: A patient who presented with facial nerve weakness and a painful mass of the parotid gland underwent fine needle aspiration, laboratory testing, and computed tomography of the neck that demonstrated a large parotid malignancy. The patient underwent surgical treatment followed by radiotherapy. Histologic and immunohistochemical examination of the specimen was performed. RESULTS: This report of a slow-growing parotid mass with otalgia and facial nerve weakness was treated with radical parotidectomy, supraomohyoid neck dissection, and cable graft repair of the excised facial nerve, which was completely encircled by tumor. Postoperative radiotherapy was administered. Histologic and immunohistochemical evaluation demonstrated carcinosarcoma. CONCLUSIONS: Carcinosarcoma is an unusual tumor of the parotid gland. Treatment generally involves surgery with subsequent radiotherapy. Long-term close follow-up is recommended, for this tumor has a high propensity for both local and regional recurrence and metastasis.     

Selective deep lobe parotid surgery for benign tumors

Conclusions: Deep-lobe tumor parotidectomy decreases the incidence of parotidectomy post-surgical complications, preserves parotid function, and has a good esthetic appearance. Objective: The existing surgical technique in the parotidectomy of deep-lobe benign tumors can be improved. Methods: Fourteen surgical operations were performed (2004–2015) for selective deep lobe parotidectomy for patients with primary benign parotid tumors. The patients with deep-lobe benign tumors were operated on with the method of superficial lobe preservation, which included methylene blue staining of the gland and intra-operative facial nerve detection. Results: During follow-up, no cases of tumor recurrence, permanent facial nerve injury, postparotidectomy depression, or Frey’s syndrome was found.     

Limitations of magnetic resonance imaging in the evaluation of perineural tumor spread causing facial nerve paralysis

OBJECTIVE: To present and discuss the clinical presentation and treatment in patients with long-duration unilateral facial paralysis and normal magnetic resonance imaging (MRI) findings. DESIGN: Case series. SETTING: Ear, nose, and throat department of the University of Cologne, Cologne, Germany. PATIENTS: A total of 486 patients with unilateral facial paralysis who were treated from 1986 to 1998. Besides the usual diagnostic workup, a complete electrophysiological evaluation, including investigations such as needle electromyography and neuromyography (also known as electroneurography), of the facial nerve was performed at repeated intervals. In 19 patients, a malignant tumor was delineated with ultrasonography or MRI. In 8 of these patients, the initially performed MRI did not detect any parotid gland lesion causing the paralysis, whereas long duration of the paralysis and electroneurography indicated malignancy. RESULTS: Exploration surgery was performed as total parotidectomy in these 8 patients and malignant parotid gland tumors were proved in all 8 patients. CONCLUSIONS: Individuals with facial nerve paralysis without any signs of regeneration 6 months after the onset of paralysis and/or persistent electrophysiological evidence of ongoing neuronal degeneration should undergo surgical exploration of the parotid gland and facial nerve, even if MRI studies show no tumoral lesion.     

Exophytischer Parotistumor

An 81-year-old male patient presented at our department with a large (diameter 10 cm), exophytic lesion in the right parotid region. Magnetic resonance imaging showed the tumor to derive from the lateral part of the parotid gland. We performed complete tumor resection with selective ipsilateral neck dissection. The facial nerve could be preserved. The postoperative course was uneventful. Histopathologic and immunohistochemical examinations revealed a malignant fibrous histiocytoma. We present the diagnostic and therapeutic options of this unusual malignancy of the parotid gland.     

Limited parotidectomy: the role of extracapsular dissection in parotid gland neoplasms

OBJECTIVE: Surgical techniques for parotid gland neoplasm removal have been shaped over the years by the importance of the gland's relationship with the facial nerve, histologic behavior of parotid tumors, and recurrence rates from specific techniques. Parotidectomy with facial nerve dissection has become the procedure of choice in removal of parotid gland neoplasms because of the resulting low recurrence rate. However, these more comprehensive dissections can cause significant postoperative complications, some cosmetically devastating. We propose that a more limited dissection yields a similar low recurrence rate but with less risk of complications. STUDY DESIGN: Retrospective case series. METHODS: A retrospective review of the clinical outcomes and pathology of 27 patients who underwent extracapsular dissection for parotid gland neoplasms. RESULTS: All tumors were located in the superficial lobe of the parotid gland and size of the masses ranged from 4.0 to 1.0 cm (mean 2.4 cm) in diameter. Pathology of the parotid tumors consisted of 11 pleomorphic adenomas, six Warthin's tumors, six benign epithelial cysts, one sarcoid lesion, two lymphoid hyperplasia, and one Kaposi's sarcoma. There were no cases of capsular rupture. There was no temporary or permanent facial paralysis and no incidence of Frey's syndrome. One patient developed a sialocele, which was aspirated and resolved after 3 months. There were no recurrences with follow-up times between 5 months and 6 years (mean 41 mo). CONCLUSION: We advocate extracapsular dissection for benign parotid neoplasms because of the acceptable recurrence rates with limited complications as compared to superficial parotidectomy.     

Benign tumors of the parotid gland

We review patients operated of parotidectomy in our ENT department of Dr. Peset Hospital from Valencia during the period 1975-2001. We shelted an amount of 145 cases. The pathologic distribution between benign and malign tumors was as following: 119 benign tumors (83%) and 26 malign tumors (17%). Here we study benign parotid tumors, which represent 83% of total parotid tumors. We performed suprafacial parotidectomies in 72% and total parotidectomy in 19% of cases. Nodulectomy was realized in 9% of patients in those tumors that arise in the lower part of the parotid gland and usualy they were Warthin tumors. The main complications of surgery were facial nerve dysfunction and Frey syndrome. We didn't have any case of permanent facial nerve dysfunction but transitory facial nerve disfunction occurred in 26% of patients. Frey syndrome appeared in 10% of patients operated of parotidectomy. Benign mixed tumor was the only one benign tumor in recurring and the frequency was 5% of patients.     

Recurrent benign pleomorphic adenoma of the parotid gland: Facial nerve identification and risk factors for facial nerve paralysis at re-operation

ObjectiveSurgery for recurrent pleomorphic adenoma of the parotid gland is challenging since there is a considerable risk of facial nerve injury and a high re-recurrence rate. We investigated surgery for recurrent pleomorphic adenoma, focusing on management of the facial nerve.MethodsWe reviewed 29 patients who underwent surgery for recurrent benign pleomorphic adenoma of the parotid gland at our department between 1999 and 2018. We examined clinicopathologic features and risk factors for facial nerve injury during reoperation.ResultsFactors associated with difficulty in identifying the main trunk of the facial nerve during surgery were bilobar tumors, multiple tumors, and use of an S-shaped skin incision at the previous operation. When the facial nerve was identified intraoperatively, it could be preserved in 2/3 of patients, while the nerve was only preserved in 1/3 of patients when it was not identified. Factors related to permanent postoperative paralysis included recurrence in the deep lobe or both lobes and multiple tumors.ConclusionThe probability of successfully preserving the facial nerve is relatively high if the nerve can be identified during surgery for recurrent pleomorphic adenoma, although intentional resection is necessary in some patients. Factors associated with difficulty in identifying the facial nerve are similar to those related to permanent postoperative paralysis, including bilobar tumors and multiple tumors. In patients with recurrent pleomorphic adenoma, preservation of the facial nerve is difficult, when they may have undergone previous extensive resection or have multiple tumors requiring subtotal or more extensive resection.     

Management of parotid gland surgery in a university teaching hospital

The aim of our study was the evaluation of two controversial procedures used in surgical management of parotid tumours in a university teaching hospital: fine needle aspiration cytology (FNAC) and continuous operative facial monitoring with nerve integrity monitor (NIM). We present a retrospective study of 96 consecutive cases of parotid gland surgical procedures, performed in our department of ENT Surgery (Bichat University Hospital) during a 2-year period. After the exclusion of nine patients (4 recurrent tumours, 3 insufficient data and 2 obviously malignant tumours with preoperative facial paralysis and necessary peroperative facial nerve sacrifice), the final group included 40 men and 47 women (mean age 46 years). FNAC, final histological diagnosis, NIM use, postoperative facial disorders and operative time were analysed. Other variables included age, sex, type of surgery and other postoperative complications. FNAC: 78 patients underwent FNAC. Positive predictive value for malignancy was 100%; negative predictive value 94.4%; sensitivity 63.6%; specificity 100%. NIM: surgery was performed without NIM for 41 patients, with for 46 patients. There was no significant difference in occurrence of facial disorders between the two groups. Operative time was significantly lower in group operated with NIM for extracapsular dissection, superficial parotidectomy and total parotidectomy. Because continuous efforts of modern health systems to improve operating room schedules may threaten resident surgeons training, using NIM and performing preoperative FNAC may help operative planning and improve medical education in a teaching hospital.