Cysts, masses, and tumors of the accessory parotid gland.

An accessory parotid gland occurs in approximately 21 percent of human subjects. It is located anterior to the main parotid gland, usually just above Stensen's duct and connected by its own duct to the latter. Any lesions that can occur in the main parotid gland can also arise in an accessory parotid gland. For the excision of lesions of the accessory parotid gland, we prefer to turn the same cervicofacial flap used for a lateral or total parotidectomy. This permits one to fully visualize the superficial and deep main parotid segments, the trunk and the branches of the facial nerve, and the accessory parotid gland along with its duct system and Stensen's duct.     

The safe face lift with bony anatomic landmarks to elevate the SMAS

The risk for facial nerve injury has been reported to be increased with the inclusion of superficial musculoaponeurotic system (SMAS) elevation as compared with a skin-only face lift. The facial nerve courses through the parotid gland. The SMAS is elevated superficial to the parotid gland. However, in elevating the SMAS anterior to the parotid gland, the facial nerve is at risk of injury where its branches emerge from the anterior edge of the parotid gland. The purpose of this study was to identify bony anatomic landmarks to predict the location of the anterior edge of the parotid gland to avoid injury to the facial nerve branches as they exit the parotid gland. The authors dissected 20 cadaver face halves to determine bony landmarks-the masseteric tuberosity and the inferior lateral orbital rim-to predict the location of the anterior parotid edge. Then they measured the anterior edge of the parotid gland in relation to the vector formed between these two bony landmarks. They identified and measured the most anterior portion of the parotid gland in relation to this vector. Then the most posterior aspect of the parotid gland in relation to this vector was measured. In the 20 dissections, the authors found the most anterior portion of the parotid gland to be 2.7 +/- 1.0 mm anterior to the vector from the inferior lateral orbital rim to the masseteric tuberosity. The most posterior part of the anterior edge of the parotid gland in relation to this vector was found to be 1.0 +/- 1.5 mm posterior to this vector. The parotid gland measured an average of 38.8 +/- 3.5 mm in width from the tragus to the anterior parotid edge. In elevating the SMAS with a face lift, the facial nerve branches can be predicted to exit the anterior edge of the parotid gland, which can be located 38.8 mm anterior to the tragus and near the vector from the inferior lateral orbital wall to the masseteric tuberosity.     

Sebaceous lymphadenoma identified by fine needle aspiration biopsy: a case report

BACKGROUND: Sebaceous lymphadenoma of the parotid gland is a rare benign neoplasm. This is the first reported case of fine needle aspiration biopsy (FNAB) findings for sebaceous lymphadenoma of the parotid gland. CASE: A 60-year-old male presented with painless, bilateral parotid swelling noted for 5 months. The swelling was more pronounced on the right. Examination revealed bilaterally prominent parotid glands with diffuse firmness but no discrete masses. There was no evidence of facial nerve dysfunction. Laboratory evaluation was negative for infectious and autoimmune etiologies. Magnetic resonance imaging revealed bilateral cystic parotid masses. FNAB of the right parotid was obtained to assist with preoperative counseling. It revealed lymphoid and salivary gland parenchymal cells. The patient underwent a right superficial parotidectomy. The surgical specimen of the parotid mass confirmed the diagnosis of sebaceous lymphadenoma on the tissue section. The contralateral parotid mass had not been excised at this writing. CONCLUSION: This report is the first to describe the FNAB findings of the unusual benign parotid neoplasm sebaceous lymphadenoma. Though the definitive diagnosis of any parotid mass requires tissue, generally obtained via parotidectomy, an FNAB diagnosis can be useful in counseling a patient prior to definitive biopsy.     

Acquisition of cholinergic and peptidergic properties by sympathetic innervation of rat sweat glands requires interaction with normal target

The sweat glands, a target of cholinergic sympathetic neurons, were replaced with parotid gland, a target of noradrenergic sympathetic neurons, in neonatal rats. This transplantation paradigm allowed sympathetic neurons that would normally innervate the sweat glands and develop a cholinergic phenotype to innervate the parotid gland instead. The innervation of the transplanted parotid gland did not develop a cholinergic phenotype, as assessed by choline acetyltransferase activity and acetylcholinesterase immunoreactivity, but continued to express intense catecholamine fluorescence. In addition, immunoreactivity for vasoactive intestinal peptide, normally expressed by the sympathetic innervation of the sweat glands but not the parotid, was observed in only a small percentage of the parotid-associated fibers. These results suggest that cellular interactions between neurons and their targets play an important role in the differentiation of mature neurotransmitter and neuropeptide phenotypes in vivo.     

Does a superficial musculoaponeurotic system exist in the face and neck? An anatomical study by the tissue plastination technique

An exact knowledge of the subcutaneous layers in the different regions of the face and neck is important in several surgical disciplines. In the parotid region, a superficial musculoaponeurotic system (SMAS) has been described. The existence of a SMAS as a guiding structure for the surgeon in the other regions of the face and neck has been discussed but is controversial. Therefore, the authors investigated the development of the subcutaneous connective-tissue layers in the different facial regions and in the neck. They studied these regions in 22 human fetuses using the technique of plastination histology and in three newborn and three adult specimens using sheet plastination. In addition, they dissected the neck and face in 10 fresh adult cadavers to identify the SMAS as in the surgical situation. The results show that no SMAS could be detected in any facial regions other than the parotid region. In the parotid region, it is thick and attached to the parotid sheath. However, it becomes very thin, discontinuous, and undissectable in the cheek area. No SMAS can be found in the neck, in which the authors are the first to describe a fascia covering both sides of the platysma. This fascia has close topographical connections to the subcutaneous layers of the adjoining regions. On the basis of these findings, the surgical pathways have to be defined regionally in the face. A "platysma fascia" can be considered as a surgical landmark in the neck. Therefore, the authors conclude that it is not justified to generalize a SMAS as a surgical guiding structure.     

Unilateral, multicentric Warthin's tumor mimicking a tumor metastatic to a lymph node. A case report

BACKGROUND: Warthin's tumor may be associated with false positive diagnoses of malignancy on fine needle aspiration. The most common cause of error is markedly atypical squamous metaplasia mimicking metastatic cystic squamous carcinoma. The common location of Warthin's tumors within periparotid nodes may add to the clinical suspicion of metastasis. We report a case of unilateral, multicentric Warthin's tumor arising in periparotid and intraparotid glands, leading to a strong clinical and cytologic suspicion of malignancy. CASE: A 60-year-old female presented with a 3-month history of several enlarged lymph nodes in the right side of the neck. Fine needle aspiration, performed at the right upper neck lymph node, suggested the possibility of metastatic tumor. On computed tomography and ultrasonography there were 4 nodular lesions in the right retromandibular area and lateral aspect of the neck, 1-1.5 cm in diameter. A thyroid scan revealed diffuse enlargement of the thyroid gland and a nodular lesion in the right lobe. Right thyroid lobectomy and modified radical neck dissection, including right superficial parotidectomy, were performed for evaluation of occult malignancy. Histologically we confirmed that the tumor was a synchronous, multicentric Warthin's tumor arising in the parotid gland and intraparotid and paraparotid lymph nodes. CONCLUSION: Clinicians and pathologists should consider an extraparotid Warthin's tumor in the differential diagnosis of multiple cervical masses.     

改良手术方法在腮腺肿瘤手术中的运用

目的：改良腮腺肿瘤手术方法,以期最大程度恢复术后患者美容及功能。方法：采用以下改良术式：①采用隐蔽的面部除皱切口,避免了常规术式的颈部切口;②采用总干法解剖面神经,减少了面神经周围支损伤的机率;③保留耳大神经,避免术后耳垂麻木;④采用口腔修复膜,减少了术后Frey综合征的发生;⑤采用蒂在上方的胸锁乳突肌肌瓣填塞腮腺切除后的凹陷区,避免了常规术式后的面部畸形。结果：采用该方法对36例患者行腮腺切除术,术后随访6月～4年,患者面部疤痕不明显,外形恢复良好,无面瘫,无Frey综合征出现。结论：改良的腮腺切除术克服了传统术式的缺陷,值得进一步推广和普及。     

Postnatal expression and denervation induced up-regulation of aquaporin-5 protein in rat sweat gland

The evolution of aquaporin-5 (AQP5) expression during postnatal development has not been defined in the sweat gland. Previous studies have suggested that AQP isoforms in several peripheral targets are regulated by a neural mechanism. We have examined, in rat sweat glands, the expression of AQP5 during postnatal development and the effects of denervation on AQP5 expression. Both AQP5 mRNA and protein begin to be expressed at postnatal day 10, before sweat-secretory responsiveness first appears; this expression coincides with the occurrence of vasoactive intestinal peptide (VIP) immunoreactivity. Early noradrenergic and later cholinergic interaction between sweat glands and their innervation are disrupted by neonatal chemical sympathectomy or postnatal severance of the sciatic nerve. Examination of such denervated developing rats has shown that secretory responsiveness fails to arise later in the adults, and AQP5 immunostaining increases in the denervated glands, whereas gland morphogenesis and the occurrence of AQP5 expression proceed normally. Immunobloting has revealed an increase of AQP5 abundance after the denervated mature glands lose their secretory ability. These findings suggest that AQP5 protein is necessary for sweat secretion, and that the expression of AQP5 in rat sweat glands is independent of sympathetic innervation. Our data also indicate that factor(s) regulating the normal morphological development of sweat gland might be responsible for controlling AQP5 expression.     

Metastatic minor salivary gland colloid carcinoma in the parotid region after parotidectomy for pleomorphic adenoma: a case report

BACKGROUND: Primary colloid or mucinous carcinoma of the salivary glands is extremely rare. Only a few cases have been reported that originated in the minor salivary glands. an even more exceptional presentation is as a metastatic tumor in the parotid region subsequent to superficial parotidectomy for pleomorphic adenoma. The case presented here posed a diagnostic dilemma that could be resolved only after a thorough reevaluation of the previous cytologic and histologic material and detection of the occult primary tumor in the hypopharynx following an extensive clinical and radiologic workup. CASE: A 75-year-old female underwent fine needle aspiration of the left parotid and was diagnosed as having pleomorphic adenoma. A superficial parotidectomy removed the tumor completely, and the diagnosis was confirmed. Six months following the surgery, the patient developed an enlarged nodular mass in the ipsilateral parotid region, with fine needle aspiration showing colloid (mucinous) adenocarcinoma, which proved to be a metastatic colloid (mucinous) carcinoma on excisional biopsy. The clinical and radiologic workup in search of a primary lesion led to an occult tumor in the left hypopharyngeal mucosa. CONCLUSION: Unusual presentations of rare tumors can cause considerable diagnostic difficulties to both the clinician and cytopathologist. Awareness of these rarities is important to ensure the best patient care and to avoid unnecessary investigative and therapeutic procedures.     

Vasoactive intestinal peptide and substance P in salivary glands of the rat following denervation or duct ligation

Immunoreactive vasoactive intestinal peptide (VIP) and substance P (SP) were studied in parotid, submaxillary and sublingual glands of the rat. The concentration of VIP was highest in the submaxillary gland and lowest in the parotid gland. The concentration of SP was highest in the parotid gland; it was at, or below the limit of detection in the sublingual gland. In the parotid gland the total amounts of VIP and SP were reduced by 95% after parasympathetic denervation (section of the auriculo-temporal nerve). In the submaxillary gland the total amounts of the peptides were unchanged after parasympathetic decentralization (section of the chorda-lingual nerve). In this gland the total amount of SP was reduced by 92% and that of VIP by 50%, when the chorda tympani nerve fibres were cut deep into the hilum. Cutting the nerve fibres at the hilum left the total amounts of the peptides unchanged in the submaxillary gland, whereas in the sublingual gland the total amount of VIP was reduced by 70%. Sympathetic denervation did not reduce the total amounts of the peptides. Duct ligation caused gland atrophy. In the parotid gland the total amounts of VIP and SP were reduced by 40%. In the submaxillary gland the same percentage reduction occurred with regard to SP; however, the total amount of VIP was reduced by 99%. The VIP- and SP-containing nerve fibres reach the salivary glands by the parasympathetic nerves. In both submaxillary and sublingual glands a certain fraction of VIP originates within the glands.     

Radiation injury of the parotid glands during treatment for head and neck cancer: assessment using dynamic contrast-enhanced MR imaging

The parotid gland is an important organ at risk of complications of radiotherapy for head and neck cancer. In this study, we examined the potential of dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) for assessment of radiation injury to the parotid glands. DCE-MRI was performed before and 3 months after radiotherapy in patients treated for head and neck cancer. DCE-MRI was analyzed using the pharmacokinetic model proposed by Tofts and Kermode to produce three DCE parameters: k(trans), v(e) and v(p). These parameters were correlated with the dose of radiation delivered to the parotid glands and the degree of radiation-induced parotid atrophy. The mean radiation dose received by the parotid glands was 47.1 ± 6.6 Gy. All patients received concurrent chemotherapy. There was a significant rise in all three parameters after therapy (P < 0.0001). Baseline v(e) and v(p) and the post-treatment rise in v(e) correlated with parotid gland atrophy (P = 0.0008, 0.0003 and 0.0022, respectively). DCE-MRI has the potential to be used as a non-invasive technique for predicting and assessing radiation injury in the parotid glands.     

Neonatal treatment with nerve growth factor antiserum eliminates cholinergic sympathetic innervation of rat sweat glands

Most mammalian sympathetic neurons are noradrenergic, and their dependence upon nerve growth factor (NGF) for survival during development is well established. A minor population of sympathetic neurons, including those that innervate sweat glands, is cholinergic. To determine whether cholinergic sympathetic neurons, like their noradrenergic counterparts, require NGF during development, neonatal rats were treated with NGF-antiserum and 3 weeks later their sweat glands were examined for the presence of innervation. Acetylcholinesterase (AChE) staining and vasoactive intestinal polypeptide-like immunoreactivity (VIP-IR) which mark the mature sweat gland innervation were absent from the sweat glands of the anti-NGF treated animals. Further, when the glands were examined with the electron microscope, no axons or nerve terminals were evident. These observations indicate that the elaboration of the sweat gland plexus is NGF-dependent and suggest that at least one population of cholinergic sympathetic neurons in the rat requires NGF for survival. Our findings are consistent with the idea that during development NGF is a required trophic factor not only for noradrenergic sympathetic but also for cholinergic sympathetic neurons.     

Spontaneous infarction of a parotid gland pleomorphic adenoma. Report of a case with cytologic and radiographic overlap with a primary salivary gland malignancy.

Pleomorphic adenoma is the most common neoplasm of the parotid gland, generally presenting as a slowly enlarging, firm, well-circumscribed, painless nodule. Occasional cases have presented after a short period of rapid growth or have been associated with pain. The vast majority of these tumors are solid, but rare examples have been associated with cystic degeneration or hemorrhage. Spontaneous and tumor-associated infarction of the parotid has been reported, but these examples have been limited to infarctions of Warthin's tumors and postoperative infarctions of salivary glands. We present the case of a 48-year-old male with a one-year history of a painful, enlarging, left parotid mass associated with paresthesia of the tongue. Computed tomographic examination of the parotid demonstrated a left superficial lobe mass with a rim of enhancement and low attenuation center. Fine needle aspiration yielded necrotic debris and atypical squamous elements that were thought to be compatible with carcinoma. A superficial parotidectomy with intraoperative frozen section revealed a pleomorphic adenoma with extensive central necrosis. To our knowledge, this represents the first reported case of an infarcted pleomorphic adenoma and illustrates the potential for misinterpretation of these cytologic and radiologic findings as indicative of malignancy.     

口腔修复膜植入预防腮腺手术后Frey综合征

目的：观察口腔修复膜（异种脱细胞真皮基质）植入对腮腺术后Frey综合征的预防作用。方法：我科近五年来施行的腮腺手术病人共75例,其中35例选择在皮瓣与腮腺床之间植入口腔修复膜,术后随访1-2年,以患者主观症状判断是否存在Frey综合征。结果：在未使用口腔修复膜的患者中,有29例（72．5％）出现Frey综合征的症状,在使用修复膜的患者中只有1例（2．9％）出现症状。两组之间有显著性差异（P〈0．01）。结论：口腔修复膜（异种脱细胞真皮基质）能有效预防腮腺手术后Frey综合征的发生。     

The sympathetic and parasympathetic nature of neuropeptide Y-immunoreactive nerve fibres in the major salivary glands of the rat

Summary The distribution and origin of neuropeptide Y in the major salivary glands of the rat was studied by indirect immunofluorescence technique. Numerous nerve fibres immunoreactive for the peptide were seen in the parotid and sublingual glands. Most of the fibres were located around blood vessels and salivary acini. In the submandibular gland the number of immunoreactive nerve fibres around the acini was lower in comparison with that in the parotid and sublingual glands. Some immunoreactive nerve fibres were also found around or along intra- and interlobular ducts in all major salivary glands.A large number of the neuropeptide-containing neuronal cell bodies and nerve fibres were detected in the sympathetic superior cervical ganglion. Sympathetic postganglionic nerve trunks of this ganglion contained numerous immunoreactive nerve fibres as well. A subpopulation of the neuronal cell bodies in the submandibular ganglion were immunoreactive to neuropeptide Y.Both uni- and bilateral superior cervical ganglionectomies caused a significant decrease in the number of immunoreactive nerve fibres around the blood vessels in all the major salivary glands. However, these denervations did not affect the density of nerve fibres around the acini and ducts. On the contrary, unilateral parasympathetic denervation by sectioning the auriculotemporal nerve reduced the fibres around the secretory acini in the parotid gland remarkably, while only a minor reduction in the density of immunoreactive fibres associated with the blood vessels of the gland was detected. Unilateral electrocoagulation of the trigeminal nerve branches caused no detectable change in the density of immunoreactive nerve fibres in any of the major salivary glands.On the basis of the present findings it is concluded that neuropeptide Y-reactive nerve fibres present in all major salivary glands around the blood vessels seem to be mainly sympathetic, whereas those around the acini and ducts seems to be of parasympathetic origin.     

腮腺肿瘤患者行游离保留SMAS术后的复发及预后影响因素分析

摘要 目的：探讨腮腺肿瘤患者行游离保留SMAS术后的复发及预后影响因素分析。方法：以我院2016年3月-2022年1月收治的60例腮腺肿瘤患者作为研究对象。所有患者均行游离保留SMAS联合全腮腺切除术治疗。术后进行随访。采用χ²检验和独立样本t检验进行腮腺肿瘤患者预后复发及预后存活情况的亚组分析。采用Pearson检验进行相关性分析;采用Cox回归模型计算腮腺肿瘤患者预后的独立危险因素。结果：复发和未复发患者性别、年龄、BMI、糖尿病病史和高血压病史无显著差异（P＞0.05）;复发和未复发患者的淋巴结转移、病理类型、TNM分期、AJCC临床分期差异显著（P<0.05）;预后死亡和预后存活患者性别、年龄、BMI、糖尿病病史和高血压病史无显著差异（P＞0.05）;预后死亡和预后存活患者的淋巴结转移、病理类型、TNM分期、AJCC临床分期和复发情况差异显著（P<0.05）;淋巴结转移、病理类型、TNM分期、复发、AJCC临床分期与腮腺肿瘤患者预后存活情况密切相关（P<0.05）;多因素Cox分析结果显示,淋巴结转移、病理类型、TNM分期、复发、AJCC临床分期是独立危险因素（P<0.05）。结论：疾病相关因素是导致腮腺恶性肿瘤患者复发和死亡的重要因素,临床早期可针对性调整治疗方案以降低患者术后复发和恶性肿瘤。     

Three-dimensional reconstructed eccrine sweat glands with vascularization and cholinergic and adrenergic innervation

Functional integrity of the regenerated tissues requires not only structural integrity but also vascularization and innervation. We previously demonstrated that the three-dimensional (3D) reconstructed eccrine sweat glands had similar structures as those of the native ones did, but whether the 3D reconstructed glands possessing vascularization and innervation was still unknown. In the study, Matrigel-embedded eccrine sweat gland cells were implanted under the inguinal skin. Ten weeks post-implantation, the vascularization, and innervation in the 10-week reconstructed eccrine sweat glands and native human eccrine sweat glands were detected by immunofluorescence staining. The results showed that the fluorescent signals of general neuronal marker protein gene product 9.5, adrenergic nerve fiber marker tyrosine hydroxylase, and cholinergic nerve fiber markers acetylcholinesterase and vasoactive intestinal peptide embraced the 3D reconstructed glands in circular patterns, as the signals appeared in native eccrine sweat glands. There were many CD31- and von Willebrand factor-positive vessels growing into the plugs. We demonstrated that the 3D reconstructed eccrine sweat glands were nourished by blood vessels, and we for the first time demonstrated that the engineering sweat glands were innervated by both cholinergic and adrenergic fibers. In conclusion, the 3D reconstructed eccrine sweat glands may have functions as the native ones do.     

Effects of selective denervation and nerve growth factor on activity-mediated growth of rat parotid gland.

A dietary change from all liquid to solid food is followed by an average increase of 200% in [3H]thymidine uptake into the parotid gland of rat. However, removal of either the parasympathetic (Px) or the sympathetic (Sx) innervation to the parotid gland prior to the dietary change resulted in a partial inhibition of the increase; values for the parasympathectomized gland were 51% of those of the innervated gland, and values of the sympathectomized parotid gland were 42% of those of the innervated gland. Removal of both autonomic nerves caused a complete inhibition. Initiation of nerve growth factor (NGF) injection (1 microgram/kg body wt, two times daily for the 2 days of chow refeeding) at the time of chow refeeding had no effect on completely or partially denervated glands, and thymidine values for the denervated parotid gland of rats given NGF did not differ statistically from those of rats not given NGF. With parasympathectomy, sympathectomy, and complete denervation, weight of parotid gland was decreased from that of innervated glands, and administration of NGF had no effect on the denervation-induced decreases. The data show that both branches of the innervation to parotid gland must be intact to ensure a maximal increase in thymidine uptake with the dietary change from liquid to solid food. The level of the enzyme, beta 1-4 galactosyltransferase, involved in proliferation, also depended on the presence of intact nerves. Enzyme activity of innervated parotid gland showed an average increase of 200% with chow refeeding of rats previously on liquid diet, but with Px, the average increase was 51% of that of the innervated parotid, and with Sx, it was 41%. NGF administration did not cause any change in levels of this enzyme in any Px or PxSx parotid gland and only a small change in Sx parotid; it did increase levels of this enzyme in parotid of rats without submandibular-sublingual glands.     

The effect of phenylephrine on excretion of fluid and electrolytes by the parotid and mandibular glands of the rat

The effect has been investigated of the alpha-adrenergic agonist, phenylephrine, on excretion of water and electrolytes (Na, K, and HCO3) by the parotid and mandibular glands of the rat. In the mandibular glands the agonist was as effective as acetylcholine (or parasympathetic nerve stimulation) in stimulating secretion, and the electrolyte excretory patterns seen in the two modes of stimulation were similar. In the parotid gland, phenylephrine was only one-fifth as potent as acetylcholine (or parasympathetic nerve stimulation) in evoking a secretory response but, when due allowance for flow rate differences is made, the electrolyte excretion patterns were similar. In both glands the secretory response to phenylephrine was totally different, in magnitude and in electrolyte excretion pattern, to that evoked by the beta-adrenergic agonist, isoprenaline. It is concluded, as has already been established for secretion of exportable protein, that alpha-adrenergic agonists have very similar effects to muscarinic agonists both on endpiece and on duct cells and that these actions are completely different from those evoked by activation of beta-adrenergic receptors.     

Secretory and structural changes in the parotid salivary gland of sheep and lambs after parasympathetic denervation.

The effect of the parasympathetic nerve supply on the development of the parotid gland in the immature lamb and its maintenance in the adult sheep has been investigated by unilateral postganglionic denervation. Seventy-seven to ninety-three days after denervation secretory activity of the gland was examined and material taken for histological examination. The adult denervated glands secreted at lower rates than the innervated and their atropine-resistant secretory flow was reduced to as low as one fifth of that of the innervated glands. In two lambs an atropine-resistant flow did not develop in the denervated glands: in another two, flows of saliva from the denervated glands were present but were much less than in the contralateral innervated glands. After denervation glands were, with one exception, smaller than the contralateral innervated glands. The acinar cells of the denervated adult and lamb glands were smaller than the cells of the innervated glands but similar in size to those of 7-14 day old unoperated control lambs. Acinar cells in denervated glands had periodic acid Schiff staining material but the staining reaction to pyronin-methyl green was similar in the innervated and denervated. The results indicate that the integrity of the parasympathetic innervation is essential for the development of the parotid gland of the sheep and for its maintenance in the adult animal.