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Background: Diabetes mellitus is a prevalent metabolic disorder that can result in the non-enflamatuar enlargement of the parotid gland. It is recognised as a condition that can impair microvascular perfusion., Material and Methods: The parotid glands of 38 individuals with diabetes and 38 healthy controls were examined bilaterally using ultrasound to assess parameters of volume, stiffness and microvascularity., Results: A statistically significant increase in parotid gland volume and a statistically significant decrease in microvascularity were observed in diabetic patients. Furthermore, a statistically significant increase in parotid gland volume was noted in diabetic individuals who were using antidiabetic drugs in comparison to non-users. A significant negative correlation was identified between the duration of exposure to diabetes and microvascularity., Conclusions: Ultrasonographic imaging can be used to assess the dimensions and microvascularity of the parotid gland.

Background: We compared the ultrasound features, superb microvascular imaging (SMI) and micro vessel density (MVD) of pleomorphic adenoma (PA), Warthin's tumor (WT) and basal cell adenoma (BCA) to explore the clinic value of SMI in differential diagnosis of benign tumors of parotid gland., Methods: The vascular distributions and grade by color doppler flow imaging (CDFI) and SMI, as well as vascular index (VI) of 249 parotid gland masses from 217 patients were analyzed., Results: The internal echogenicity of BCA are more homogeneous in comparing with WT and PA(P < 0.05). By SMI, the vascular distribution and vascular grade in PA were mainly peripheral (33.1%) and avascular (25.7%), Grade 1 (27.8%) and Grade 0 (25.7%). WT were mainly central (31.3%) and mixed distribution (34.9%), in Grade 3 (37.3%) and Grade 2 (36.2%). BCA was mainly peripheral (33.3%) and mixed distribution (33.3%), in Grade 2 (33.3%) and Grade 3 (33.3%). The overall detection rate of SMI for vascular Grade 2 and 3 was significantly higher than that of CDFI (P < 0.05). Both VI and MVD were lowest in PA, highest in WT (P < 0.001). The VI by SMI was correlated with MVD (P < 0.001). The correlation index between vascular distribution and grade by SMI and MVD were significantly higher than CDFI., Conclusion: SMI can provide low-velocity blood flow information, which is helpful for the differential diagnosis of common benign tumors of parotid gland, and is expected to be more widely used.

We examined the relationship between hemodynamics in the three major salivary glands and salivary secretion in urethane-anesthetized and sympathectomized type 2 diabetic and nondiabetic rats via laser speckle imaging and by collecting the saliva. Lingual nerve stimulation elicited rapid increases in glandular blood flow and induced salivary secretion from the three glands in both diabetic and nondiabetic rats. In the parotid gland, the magnitude of blood flow increase and salivary secretion was significantly lower in the diabetic rats when compared with the nondiabetic rats; however, this was not observed in the other glands. Although the intravenous administration of acetylcholine increased blood flow in the parotid gland in a dose-dependent manner, the response was significantly lower in the diabetic rats when compared with the nondiabetic rats. Similarly, mRNA expression levels of M1 and M3 muscarinic acetylcholine receptors in the parotid gland were relatively lower in the diabetic rats compared with the nondiabetic rats. Our results indicate that type 2 diabetes impairs parasympathetic vasodilation and salivary secretion in the parotid gland and suggest that disturbances in the cholinergic vasodilator pathway may contribute to the underlying mechanisms involved in the disruption of parasympathetic nerve-mediated glandular vasodilation.

Venolymphatic malformations (VLM) are the rare congenital disorders but the parotid gland VLMs are the rarest. Most of the parotid lesions present with unilateral swellings. Aetiology is unknown. Interestingly, this case came in OPD with the macroglossia and only complaint was cosmetic problem. Diagnosis was confirmed on the basis of Magnetic resonance imaging which is gold standard. Doppler ultrasonography showed low flow. Intra lesion electro cautery was done. There is need to focus on malformations and work to find out the causes.

Objectives: We aim to determine parotid gland elasticity values from healthy children and adolescents using shear wave elastography (SWE). We also define the degree of vascularity using superb microvascular imaging (SMI), power Doppler (PD), and color Doppler (CD) and compare SMI with CD and PD., Materials and Methods: A total of 100 cases, comprising 50 girls and 50 boys, with ages ranging from 3 to 17 years were included in this prospective study. SWE, SMI, PD, and CD measurements were taken from both parotid glands, and the relationships with sex, age, and body mass index (BMI) were determined. The SMI was compared with the PD and CD., Results: The median elasticity values measured with SWE were 8.37 ± 2.09 kPa and 1.68 ± 0.26 m/s on the right and 8.33 ± 2.04 kPa and 1.69 ± 0.26 m/s on the left. There were significant positive correlations present for those aged below and above 10 years and for BMI with elasticity values. The median vascular spot numbers measured using SMI, PD, and CD were 5 ± 1.70, 3.5 ± 1.45, and 2 ± 1.1 on the right and 4 ± 1.7, 4 ± 1.43, and 2 ± 1.05 on the left, respectively. The median values obtained with SMI were significantly higher than the median values obtained with both PD and CD., Conclusion: This study determined the reference SWE, SMI, PD, and CD values for normal parotid glands in healthy children and adolescents. Elasticity values were affected by age and BMI. There was no correlation between vascularity values and age, sex, or BMI. SMI provided more detailed information about vascularity compared with the other methods.

A 44-year-old man presented with swelling in the left parotid region. The swelling was firm and Fine Needle Aspiration Cytology report proved pleomorphic adenoma. In the CT scan, the tumour was confined to the superficial lobe of parotid. So, left superficial parotidectomy was planned. Modified Wilson Blair's incision was used. On course of identifying the facial nerve, a large calibre vein was identified running vertically through the parotid substance. Assuming it as retromandibular vein, further dissection was carried out more meticulously. Marginal mandibularbranch of facial nerve was identified near the angle of mandible and retrograde dissection showed the cervicofacial division running medial to retromandibular vein with the main facial nerve trunk lying unusually medial and posterior to it. Adding to it, the temporofacial division was found 'forked' between the branches of retromandibular vein. These variations in head and neck venous channels are not that rare as we believe. All these variations have an embryological basis. Therefore, knowledge and understanding of this complex anatomy will help us preventing devastating complications like bleeding and facial nerve injury in such cases., Competing Interests: Competing interests: None declared., (© BMJ Publishing Group Ltd (unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.)

Neoplasms located in the parotid region, temporal bone, infratemporal fossa, and lateral skull base represent a challenge due to their difficult anatomic location and surrounding neurovascular structures. A variety of surgical approaches are appropriate to access this area, although several of them can place the auricular blood supply in danger. If the auricular blood supply is compromised, ischemia and, eventually, avascular necrosis of the auricle can occur. Auricular necrosis often can cause patients a delay in adjuvant radiation therapy and result in the need for additional reconstructive procedures. Therefore, it is imperative to identify risk factors associated with the development of this disabling complication. We conducted a retrospective review of 32 individuals undergoing treatment of benign and malignant lesions in the parotid gland, infratemporal fossa, and lateral skull base. To identify potential risk factors for auricular necrosis, the patients were analyzed based on the type of neoplasm (malignant or benign), risk factors affecting blood flow (diabetes mellitus, smoking history, prior radiation, prior surgery), body mass index, and the length of surgery. In our population examined, 3 instances of auricular necrosis occurred. None of the potential risk factors proved to be statistically significant (although malignant pathology approached significance at p = 0.07). Two of the patients required an auriculectomy with reconstruction. The third had multiple postoperative clinic visits for surgical debridement. Although no potential risk factors were statistically significant, surgeons should remain cognizant of the auricular blood supply while performing surgery via preauricular and postauricular approaches to this area.

Purpose: To demonstrate the feasibility of intravoxel incoherent motion imaging (IVIM) for quantification of perfusion changes in the parotid gland after gustatory stimulation., Materials and Methods: Eight healthy volunteers underwent diffusion-weighted magnetic resonance imaging (MRI) of the neck at 3T with 11 dynamic acquisitions (9 b-values between 0 and 980 s/mm 2 , 2:40 min each). After 5:20 minutes, a lemon-mint-drop was administered orally. Perfusion fraction (F p ), pseudodiffusion (D*), tissue diffusion (D t ) coefficients, and optimal b-value threshold were measured using a multistep variable b-value threshold fitting approach. Dynamic changes in the coefficients between three exemplary timepoints (baseline, after stimulation, after dissolution) were compared using a Mann-Whitney U-test with Bonferroni correction (P < 0.016 significance level)., Results: Mean values (95% confidence interval [CI]) for IVIM parameters at baseline were F p : 0.11 (0.08-0.15), D*: 56.48 mm 2 /s (39.71-98.27), D t : 1.01 mm 2 /s (0.84-1.06), b-value threshold: 30 s/mm 2 (21.25-105). After stimulation: F p 0.16 (0.15-0.24; P < 0.01), D* 93.83 mm 2 /s (77.98-129.53, P = 0.25), D t 0.93 mm 2 /s (0.87-1.08, P = 0.94), b-value threshold 20 s/mm 2 (13.75-26.25 s/mm 2 , P = 0.10), reflecting the increase in tissue perfusion. After dissolution of the drop: F p : 0.13 (0.11-0.18, P = 0.38), D*: 101.61 mm 2 /s (90.68-144.55, P = 0.07), D t : 0.91 mm 2 /s (0.85-1.05, P = 0.64), b-value threshold: 15 s/mm 2 (11.25-40, P = 0.38)., Conclusion: The IVIM method allows for simultaneous quantification of changes in perfusion and diffusion effects after gustatory stimulation of the parotid gland., Level of Evidence: 2 J. Magn. Reson. Imaging 2017;45:570-578., (© 2016 International Society for Magnetic Resonance in Medicine.)

Purpose: To verify whether quantification of parotid perfusion is affected by fat signals on non-fat-saturated (NFS) dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) and whether the influence of fat is reduced with fat saturation (FS)., Methods: This study consisted of three parts. First, a retrospective study analyzed DCE-MRI data previously acquired on different patients using NFS (n = 18) or FS (n = 18) scans. Second, a phantom study simulated the signal enhancements in the presence of gadolinium contrast agent at six concentrations and three fat contents. Finally, a prospective study recruited nine healthy volunteers to investigate the influence of fat suppression on perfusion quantification on the same subjects. Parotid perfusion parameters were derived from NFS and FS DCE-MRI data using both pharmacokinetic model analysis and semiquantitative parametric analysis. T tests and linear regression analysis were used for statistical analysis with correction for multiple comparisons., Results: NFS scans showed lower amplitude-related parameters, including parameter A, peak enhancement (PE), and slope than FS scans in the patients (all with P < 0.0167). The relative signal enhancement in the phantoms was proportional to the dose of contrast agent and was lower in NFS scans than in FS scans. The volunteer study showed lower parameter A (6.75 ± 2.38 a.u.), PE (42.12% ± 14.87%), and slope (1.43% ± 0.54% s(-1)) in NFS scans as compared to 17.63 ± 8.56 a.u., 104.22% ± 25.15%, and 9.68% ± 1.67% s(-1), respectively, in FS scans (all with P < 0.005). These amplitude-related parameters were negatively associated with the fat content in NFS scans only (all with P < 0.05)., Conclusions: On NFS DCE-MRI, quantification of parotid perfusion is adversely affected by the presence of fat signals for all amplitude-related parameters. The influence could be reduced on FS scans.

Phleboliths within the parotid gland are exceedingly rare. We report a case of a venous malformation with multiple phleboliths that involved the left parotid gland and extended into the extraparotid tissue in a 43-year-old woman. We also review 13 similar cases that have been reported since 1948, and we highlight the significance of distinguishing phleboliths from sialoliths because management of the two can be entirely different. Phleboliths in and around the salivary glands primarily affect the parotid and submandibular glands in adult women. Patients can present with recurrent, intermittent swelling that may be associated with food intake and hyposalivation. Any sialolithiasis located outside of its most common location in the submandibular glands must be investigated thoroughly before surgery.

Venous malformations of the parotid glands are uncommon and can be difficult to confirm on routine anatomical imaging alone because of overlap of imaging features with other more common parotid lesions. (99m)Tc RBC scans combined with SPECT/CT offer a noninvasive way to diagnose parotid venous malformations without the need for biopsy. Combined with anatomical findings of phleboliths (when present), the diagnosis can be reliably determined. We present a case where MRI and biopsy were inconclusive, but the SPECT/CT was used to confirm the suspicion of a benign venous malformation.

Objective: To evaluate changes in salivary gland echostructure and vascularization after rituximab treatment in patients with primary Sjögren's syndrome (SS)., Methods: Twenty-eight patients with primary SS included in the multicenter, randomized, double-blind, placebo-controlled Tolerance and Efficacy of Rituximab in Primary Sjögren's Syndrome (TEARS) trial underwent salivary gland ultrasonography before the first placebo or rituximab infusion and then 6 months later. Trial inclusion criteria were scores of ≥50 mm on at least 2 of 4 visual analog scales (VAS) evaluating dryness, pain, fatigue, and global disease; and recent-onset (<10 years) biologically active primary SS and/or systemic primary SS. Patients were randomly assigned (1:1) to rituximab (1 gm at weeks 0 and 2) or placebo. Ultrasonography of both parotid and submandibular glands was performed to assess echostructure (using a semiquantitative score of 0-4, with improvement defined as a ≥1-point decrease), size of each gland, and vascularization based on the resistive index of the transverse facial artery of the parotid gland before and after lemon juice stimulation., Results: Of the 28 patients, 5 (18%; 3 in the placebo group and 2 in the rituximab group) had clinically detectable bilateral parotid gland enlargement at baseline. Parotid parenchyma echostructure improved in 50% of the rituximab-treated patients versus 7% of the placebo-treated patients (P = 0.03). In the submandibular glands, echostructure also improved in a larger proportion of rituximab-treated patients, although the difference was not significant (36% versus 7% of placebo-treated patients; P = 0.16). Gland sizes and resistive index remained unchanged., Conclusion: Ultrasonography showed improved salivary gland echostructure in patients with primary SS receiving rituximab, with no changes in salivary gland size or vascularization, 6 months after the first infusion., (© 2015, American College of Rheumatology.)

Anterior disc displacement is one of the most common conditions affecting the temporomandibular joint. In the authors' previous publications, they reported on the basic technical elements of disc repositioning surgery. However, the present article presents some critical modifications that have allowed the safe and successful performance of this procedure during the past 3 years., (Copyright © 2015 American Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc. All rights reserved.)

Background: Vascular malformations can mimic malignant tumors, and the coexistence of both types of lesions can limit and interfere with treatment. A consecutive series of vascular malformations that were treated and evaluated in a single institute and cases involving vascular anomalies combined with malignancies or malignancies that were treated as vascular anomalies were analyzed., Objective: Absolute ethanol is used in the treatment and management of vascular malformations and is sometimes administered before a definitive diagnosis has been obtained, despite the fact that some vascular lesions are subsequently revealed to be malignant tumors. This study discusses such cases., Materials and Methods: From January 2006 to August 2012, 139 patients were treated for vascular malformations at Nagasaki University Hospital and were followed up for a minimum of 1 year., Results: Four malignant lesions coexisted with or were misdiagnosed as vascular malformations, including a malignant peripheral nerve sheath tumor located in the chest, a hemangiopericytoma of the palate, an adenoid cystic carcinoma of the cheek, and a squamous cell carcinoma of the cheek. Thus, malignant lesions were detected in 2.88% of cases in which vascular malformations were preoperatively diagnosed., Conclusion: When treating vascular malformations, it is advisable to be aware of the possibility of malignancy.

Hamartomas of the parotid gland are highly unusual. We present a case of a vascular hamartoma of the parotid gland arising as a 1.5 cm mass in a 5-year-old girl. As far as we are aware, no other case with the same features has been reported. We present this case to generate greater consideration of hamartomas as part of the differential diagnosis of parotid lesions, and to reflect over the criteria used to identify a hamartoma from other parotid lesions, as there appears to be some confusion in the literature., (2014 BMJ Publishing Group Ltd.)

Myopericytoma (MPC) is a vascular neoplasm exhibiting differentiation towards perivascular cells. Variable cytoarchitechtural features are visible within MPC, and there is much overlap between MPC, myofibroma and glomus tumours. MPC have a local recurrence rate of 10-20% and malignancy has been described in a few published cases. Previously, superficial parotidectomy has been recommended for MPC but, in this case, the surgical approach was via extracapsular dissection (ECD). A 66-year-old Caucasian man presented with a palpable mass arising from the superficial lobe of the right parotid gland. Following removal by ECD, the histopathological diagnosis of MPC was made. This is the first published report describing ECD of MPC associated with the parotid gland. ECD is preferable to superficial parotidectomy for small superficial lesions such as MPC, with similar oncological outcomes and fewer functional and aesthetic complications.

Arteriovenous malformations (AVMs) are composed of abnormally connecting feeding arteries as well as draining veins and lack a regulatory system. Frequent recurrences and unpredictable behavior are their main problems. Potential mortality and morbidity associated with therapeutic procedures must be considered with these patients. Improper treatment often aggravates the condition, potentially rendering therapy more complex. A multidisciplinary approach, including an endovascular approach, surgical excision, and flap reconstruction, is considered to completely eradicate an AVM. This study introduces a complicated case of AVM with massive bleeding through the external auditory canal that was treated with a multidisciplinary approach.

Objective: To report a case of varix of the retromandibular vein within the parotid gland., Methods: Case report, and discussion of the appropriate selection and use of radiological investigation techniques., Results: A 64-year-old lady who presented with unilateral tinnitus underwent a magnetic resonance imaging scan to exclude a vestibular schwannoma. The magnetic resonance scout images revealed an incidental finding of a hyperechoic mass within the parotid gland. The mass was most consistent with a pleomorphic adenoma. Ultrasound-guided fine needle aspiration cytology was arranged; the ultrasound identified the mass as a varix of the retromandibular vein and fine needle aspiration cytology was not performed., Conclusion: A varix of the retromandibular vein is a very rare cause of a parotid mass. Appropriate radiological investigations can prevent unnecessary invasive investigations or procedures.

Introduction: In tissues and organs exposed to large pressure amplitude low frequency noise fibrosis occurs in the absence of inflammatory signs, which is thought to be a protective response. In the parotid gland the perivasculo-ductal connective tissue surrounds arteries, veins and the ductal tree. Perivasculo-ductal connective tissue is believed to function as a mechanical stabilizer of the glandular tissue., Material and Methods: In order to quantify the proliferation of perivasculo-ductal connective tissue in large pressure amplitude low frequency noise-exposed rats we used sixty Wistar rats which were equally divided into 6 groups. One group kept in silence, and the remaining five exposed to continuous large pressure amplitude low frequency noise: g1-168h (1 week); g2-504h (3 weeks); g3-840h (5 weeks); g4-1512h (9 weeks); and g5-2184h (13 weeks). After exposure, parotid glands were removed and the perivasculo-ductal connective tissue area was measured in all groups. We applied ANOVA statistical analysis, using SPSS 13.0., Results: The global trend is an increase in the average perivasculo-ductal connective tissue areas, that develops linearly and significantly with large pressure amplitude low frequency noise exposure time (p < 0.001)., Discussion: It has been suggested that the biological response to large pressure amplitude low frequency noise exposure is associated with the need to maintain structural integrity. The structural reinforcement would be achieved by increased perivasculo-ductal connective tissue., Conclusions: Hence, these results show that in response to large pressure amplitude low frequency noise exposure, rat parotid glands increase their perivasculo-ductal connective tissue.

We report a case of ischemia of the auricle and acute parotitis that developed following embolization for epistaxis. A 53-year-old male was previously conservatively treated for epistaxis with bilateral posterior nasal packing due to hypertension. As the bleeding, continued the patient underwent bilateral embolization of the internal maxillary arteries. The bleeding was controlled but the patient developed acute ischemia of the ipsilateral parotid gland and the auricle that regressed with medical treatment., (Copyright © 2012 The American Laryngological, Rhinological, and Otological Society, Inc.)

We describe the case of a 41-year-old woman who presented to a local facial plastic surgeon for evaluation of a cosmetic defect of the cheek of 1 month's duration. When imaging revealed the presence of a vascular mass, the patient was referred to us. Further imaging identified the mass as an intraparotid external carotid artery aneurysm. The decision was then made to treat the patient with embolization of the lesion followed by surgical resection the next day. During the resection, the lateral-most aspect of the aneurysm was found to be adherent to and splaying the facial nerve. The embolized mass and the surrounding fascial layer were removed, and the branches of the facial nerve were retracted superiorly and inferiorly. Dissection proceeded around the aneurysm in this plane. Blood loss during the procedure was minimal. On postoperative day 1, the patient exhibited minimal lower facial asymmetry. In this case, performing embolization prior to surgical resection appeared to be a prudent and efficacious strategy. The preoperative embolization greatly reduced the risk of damage to the facial nerve.

Arteriovenous malformations (AVMs) of the jaws are relatively rare, with fewer than 200 cases reported in the literature. Their real importance lies in their potential to result in exsanguination, which usually follows an unrelated treatment, such as tooth extraction, surgical intervention, puncture wound or blunt injury in involved areas, with the dentist unaware of the existence of the AVM. The present case illustrates an AVM in an 18-year-old female with swelling on the right side of the face. This case report is unique because although there was no history of bleeding episodes, thorough examination and investigation diagnosed it as high-flow vascular malformation. We ascertain the importance of dentists' awareness of the fatal outcome of these lesions and emphasize that, prior to performing any procedure, necessary investigations should always be done.

Seventy patients aged 20 to 75 years with suspected parotid gland disease were examined to study the capabilities of an ultrasound study in the diagnosis of neoplasms of the major salivary glands. B-mode ultrasonography and color Doppler imaging presented a means of detecting the presence of masses in the gland, their topography and dimensions, and specific vascularization, which allowed the option and scope of treatment to be planned.

The aim of this study was to assess the effect of type 1 diabetes mellitus (induced by a single intravenous injection of 100 mg kg(-1) of alloxan) on acetylcholine (ACh)-induced relaxation in isolated rabbit parotid gland feeding artery. Isometric force measurements and quantification of inducible nitric oxide synthase (iNOS) mRNA by real-time RT-PCR were made in parotid artery rings from diabetic and control rabbits. Acetylcholine induced concentration- and endothelium-dependent vasorelaxation that was significantly decreased in parotid artery rings from diabetic rabbits. Schild analysis of the ACh vasorelaxant effect, in the presence of selective muscarinic receptor antagonists, revealed involvement of the M(3) receptor subtype in parotid artery rings from both control and diabetic rabbits, with no change in antagonist affinity constants. The inhibitory effects of indomethacin, a non-selective inhibitor of cyclooxygenase, and of high potassium, an inhibitor of hyperpolarization, on ACh vasorelaxation were increased. The effect of N(G) -nitro-l-arginine, a non-selective inhibitor of NOS, was decreased in diabetes. S-methylisothiourea, a selective inhibitor of iNOS, significantly reduced ACh vasorelaxation only in parotid artery rings from diabetic rabbits. Also, up-regulation of iNOS mRNA expression was detected in parotid artery rings from diabetic rabbits. These results suggest that in parotid artery rings from diabetic rabbits, impaired endothelium-dependent vasorelaxation to ACh appears to be caused by the loss of a nitric oxide-mediated component and increased iNOS expression, and is unlikely to be caused by a change at the M(3) receptor level., (© 2011 Eur J Oral Sci.)

The authors describe a rare presentation of a spontaneous pseudoaneurysm of the superficial temporal artery which mimicked a parotid neoplasm. The clinical presentation, possible aetiology, diagnosis, and management of this condition are discussed., (Copyright © 2010 International Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.)

Purpose: To evaluate the effect of irradiation on microvascular endothelial cells in miniature pig parotid glands., Methods and Materials: A single 25-Gy dose of irradiation (IR) was delivered to parotid glands of 6 miniature pigs. Three other animals served as non-IR controls. Local blood flow rate in glands was measured pre- and post-IR with an ultrasonic Doppler analyzer. Samples of parotid gland tissue were taken at 4 h, 24 h, 1 week, and 2 weeks after IR for microvascular density (MVD) analysis and sphingomyelinase (SMase) assay. Histopathology and immunohistochemical staining (anti-CD31 and anti-AQP1) were used to assess morphological changes. MVD was determined by calculating the number of CD31- or AQP1-stained cells per field. A terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) apoptosis assay was used to detect apoptotic cells. The activity of acid and neutral Mg(2+)-dependent SMase (ASMase and NSMase, respectively) was also assayed., Results: Local parotid gland blood flow rate decreased rapidly at 4 h post-IR and remained below control levels throughout the 14-day observation period. Parotid MVD also declined from 4 to 24 hours and remained below control levels thereafter. The activity levels of ASMase and NSMase in parotid glands increased rapidly from 4 to 24 h post-IR and then declined gradually. The frequency of detecting apoptotic nuclei in the glands followed similar kinetics., Conclusions: Single-dose IR led to a significant reduction of MVD and local blood flow rate, indicating marked damage to microvascular endothelial cells in miniature pig parotid glands. The significant and rapid increases of ASMase and NSMase activity levels may be important in this IR-induced damage., (Copyright © 2010 Elsevier Inc. All rights reserved.)

Background: Xerostomia is caused by irradiation for head and neck cancer, depending on the dose to the parotid gland. To investigate which part of the parotid gland has to be spared with radiotherapy, detailed information about the vascular supply of the parotid gland is necessary., Methods: Arterial vessels of the head of a human cadaver were colored. A 3-dimensional reconstruction of the parotid gland and the arterial vessels was made and analyzed., Results: Five arterial vessels were responsible for the vascular supply of the parotid gland: the posterior auricular artery, 2 branches so far unnamed, the superficial temporal artery, and the transverse facial artery. All arteries were branches off the external carotid artery, and supplied different parts of the parotid gland., Conclusions: This study describes the detailed vascular supply of the human parotid gland. These results may contribute to improve parotid sparing radiotherapy, thus reducing complications such as xerostomia in the future., ((c) 2009 Wiley Periodicals, Inc.)

Background: Arteriovenous malformation of the scalp resulting from blunt trauma to the head is an unusual occurrence and is rarely associated with neurological sequelae. This case details an arteriovenous malformation with a cerebral steal phenomenon., Methods: A 21-year-old man presented with an enlarging, pulsatile mass in the right facial/temporal area without known cause. CT and angiography were consistent with a large arteriovenous malformation involving the external carotid system, causing a secondary cerebral steal that resulted in neurological symptoms including seizure. Surgical resection of the mass was undertaken., Results: The patient had an uncomplicated preoperative course with complete resolution of all neurologic symptoms., Conclusion: Cerebral steal is an uncommon consequence of traumatic extracranial arteriovenous malformation. The current literature is reviewed, and the diagnostic approach as well as therapeutic options are discussed., ((c) 2009 Wiley Periodicals, Inc. Head Neck, 2009.)

We aimed to quantitatively investigate the alteration of parotid perfusion after irradiation using dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) based on a two-compartment tracer kinetic model. This study enrolled 19 patients (53.2 +/- 14.9 years) treated by head and neck radiotherapy and 19 age-relevant and sex-matched subjects as a control group. Perfusion parameters (K ( el ), k (21) and A) of parotid glands were analyzed based on the Brix model from T1-weighted DCE-MRI. Suitability of the Brix model was evaluated via Monte Carlo simulation for the goodness-of-fit. Analysis of nonlinear goodness-of-fit showed that the Brix model is appropriate in evaluating the parotid perfusion (R(2) = 0.938 +/- 0.050). The irradiated parotid glands showed significantly lower K ( el ) (P < 0.0005) and k (21) (P < 0.05) and consequently significantly higher value of peak enhancement (P < 0.0005) and time-to-peak (P < 0.0005) compared with non-irradiated ones, suggestive of gradual and prolonged accumulation and delayed wash-out of contrast agent due to increased extracellular extravascular space and decreased vascular permeability in the irradiated glands. Linear regression analysis showed dose-dependent perfusion changes of the irradiated parotid glands. We conclude that quantitative DCE-MRI is a potential tool in investigating parotid gland perfusion changes after radiotherapy.

Objective: To evaluate the usefulness of the vascularity in parotid glands in sonographic diagnosis for Sjögren syndrome., Study Design: Sonographic images of 72 cases of previously suspected Sjögren syndrome (including 43 actual cases) were analyzed retrospectively for the abnormal vascularity in the parotid gland parenchyma. The relationships between the vascularity and the results of sialographic, serologic, and histopathologic examinations were analyzed. We also compared the diagnostic accuracy of B-mode only with that of B-mode plus Doppler-mode., Results: Sjögren-positive cases showed significantly higher vascularity. As the grade of vascularity became higher, the rate of the Sjögren-negative cases became lower. The highest mean vascular score could be observed both in the initial stage and in the cavitary-destructive stage in the sialographic grades. Sensitivity and accuracy were markedly improved with vascular information., Conclusion: By using vascular information, sonographic diagnosis for Sjögren syndrome can be improved.

Purpose: To investigate the feasibility of blood flow imaging in the parotid gland using the arterial spin labeling (ASL) technique for assessment of functional changes in the parotid gland after gustatory stimulation., Materials and Methods: Anatomical and ASL imaging of the parotid gland was performed in eight healthy volunteers before and after gustatory stimulation over a period of 17 min. All measurements were carried out in a 1.5 T whole-body MR unit. ASL and data recording were performed with an adapted FAIR TrueFISP (flow-sensitive alternating inversion-recovery true fast imaging with steady precession) technique. Maps of estimated tissue blood inflow in both parotid glands were derived using a simplified model and the extended Bloch equations., Results: Delineation of the parotid glands was possible on FAIR TrueFISP images in all cases. In the 160 s period immediately after stimulation, a significant (P < 0.01) mean increase of 62% in the estimated parotid blood flow was observed. Estimated baseline blood flow before gustatory stimulation ranged from 226 to 500 mL/min/100 g (mean +/- SD 335 +/- 86). These rates increased in the 160 s immediately after stimulation to 404-772 mL/min/100 g (mean 542 +/- 108). In all volunteers, blood flow returned to near baseline values within the observation period. No statistically significant difference between the right and left parotid was observed in baseline and peak blood flow., Conclusion: ASL FAIR TrueFISP is feasible for functional characterization of the parotid glands. Assessment of changes in blood flow in the parotid gland could serve as a diagnostic tool in patients suffering from xerostomia.

Aim: We evaluated the feasibility of perfusion CT (CTP) of the parotid gland and attempted to differentiate benign from malignant tumors., Materials and Methods: CTP was performed in 17 patients with benign tumors and 10 patients with malignant parotid tumors. Data were postprocessed by using deconvolution-based perfusion analysis. Postprocessing-generated maps showed blood flow (BF), blood volume (BV), mean transit time (MTT), and capillary permeability surface product (PS). Regions of interest were placed through the tumor site and the contralateral healthy parotid tissue. Ratios of the perfusion values between the tumors and the contralateral healthy structures were also calculated. Pearson correlation coefficients were determined to compare the agreement between the two readers., Results: Perfusion maps of all tumors were successfully obtained. High Pearson correlation coefficients comparing the two readers' visually measured abnormalities were observed (r=0.79-0.86, P=0.001) for all perfusion maps, The MTT and PS values between malignant and benign tumors were not significantly different. The BF and BV values were statistically significant different between the benign and malignant tumors (0.00

Background: Long-term low-frequency noise (LFN) (

This study was undertaken to evaluate and compare the grey-scale and Doppler sonographic features of postradiotherapy (RT) and normal parotid glands. A total of 10 patients with previous head and neck RT and with different degrees of xerostomia were included. Another 10 healthy subjects, who are age and gender-matched with the 10 patients, were also recruited. Grey-scale and Doppler ultrasound examinations of parotid glands were performed on both the patients and healthy subjects. The parotid glands were assessed for their size, echogenicity, echotexture, conspicuity of intraparotid ducts, blood flow velocity and vascular resistance. Results showed that post-RT parotid glands tended to be smaller than normal parotid glands with a significant difference in the transverse dimension (p < 0.05). Normal parotid glands appeared homogeneous, hyperechoic relative to the adjacent muscles and had marginally seen intraparotid ducts. Post-RT parotid glands were heterogeneous, isoechoic (50%) or hypoechoic (50%) relative to the adjacent muscles, and the intraparotid ducts were either marginally (50%) or obviously (50%) seen on ultrasound. The PSV, RI and PI of normal parotid glands were significantly higher than that of post-RT parotid glands (p < 0.05). However, the difference in EDV between normal and post-RT parotid glands was not significant (p > 0.05). In conclusion, ultrasound is useful in assessing parotid glands. To avoid image misinterpretation, post-RT changes in the sonographic appearance of parotid glands should be considered in examining patients with previous head and neck RT.

Pteropus lylei (Lyle's flying fox), an Old World fruit bat, consumes only ripe fruit, which contains low protein and sodium. The carpophagous diet of P. lylei presents an adaptive challenge for salivary glands to conserve sufficient nutrition for living. Therefore, the parotid glands in both sexes were investigated by using light microscopy and transmission electron microscopy. No structural difference was observed in the parotid glands between sexes. The acinar cell contained dense serous secretory granules, prominent luminal microvilli and intercellular canaliculi. The intercalated duct exhibited simple cuboidal epithelium with no secretory granule. Striated duct consisted of simple columnar epithelium with basal striation, numerous elongated mitochondria, and apical vesicles. In the interlobular duct, simple tall columnar epithelium and apocrine secretion were found. The interlobar and excretory ducts surprisingly contained continuous capillaries that intervened in stratified cuboidal epithelium. In addition, there were several blood vessels around the interlobular, interlobar and excretory ducts. The morphological adaptation of the parotid gland observed in P. lylei enables this species to obtain sufficient nutrients from the preferred consumption of ripe fruit. Serous secretory granule was suitable for digestion of ripe fruit. A well-developed striated duct, continuous capillaries among the epithelial cells of interlobar and excretory ducts, and numerous blood vessels around these ducts enhanced the reabsorption of amino acids and ions. Structural variations in the parotid gland can indicate not only a correlation to diet and survival but also a close relationship of the Old World fruit bat to other kinds of bats.

Although infarction of parotid gland pleomorphic adenoma (PA) following fine-needle aspiration (FNA) has been well-documented, spontaneous infarction of PA has remained as an uncommon entity in the literature. To our knowledge, we report the second case of spontaneous infarction occurring in a parotid gland PA. A 44-yr-old man presented with a 2-yr history of slowly enlarging right parotid mass, which had become painful 1 mo before performing FNA biopsy. Smears revealed abundant necrotic debris, atypical squamous cells, and small cells with dark nuclei suggestive of a carcinoma. Histologic examination of the tissue fragments demonstrated degenerated clusters of cells and chondromyxoid matrix. The parotidectomy specimen had features consistent with those of an infarcted PA. Although appears to be rare, spontaneous infarction of PA should be considered in the differential diagnosis, since necrosis may mimic carcinoma and cause misinterpretation of necrosis as an indication of malignancy, in an otherwise benign salivary gland neoplasm.

Three adult patients with rare vascular lesions in the parotid gland including pseudoaneurysm, arteriovenous fistula and haemangioma are discussed. All patients presented with non-specific unilateral parotid mass. In all cases high-resolution ultrasound and MRI allowed accurate diagnosis and delineation of the extent of lesion. Conventional angiogram was utilized for planning definitive surgical or endovascular treatment.

Purpose: This study is carried to explore the surgical manipulation and complications of Nd:YAG laser coagulation for venous malformations in parotid gland region., Methods: The study included 84 cases of venous malformations in the parotid gland region, who underwent laser therapy after surgical approach three years ago. The results were evaluated by CT or MRI. Postoperative facial nerve function and intraoperative bleeding were analyzed., Results: Five cases had temporary facial nerve paralysis, which recovered spontaneously two months postoperatively. One case developed permanent nerve paralysis, which accounted for 1.19% in this group. The mean amount of blood loss was 200 ml. Four cases received blood transfusion., Conclusion: Careful surgical dissection and correct laser irradiation is the key to successful treatment, which could preserve facial nerve from injury and decrease bleeding.

We describe two cases of venous malformations in the parotid gland that were operated on due to cosmetic reasons. We present the main differences between hemangiomas and vascular malformations and we also emphasize the importance of correct diagnosis in vascular lesions what is crucial for selection of appropriate treatment.

Parotid vascular malformation in the adult is a very rare and benign tumor; only 47 cases were described in the world literature. This vascular malformation, mostly of venous origin is, on the opposite of the clinical, histological and evolution features of parotid hemangiomas in children, which are more frequent. Some clinical and radiological elements are pathognomonic allowing preoperative diagnosis. We present 2 cases of intraparotid venous malformation in adults, and based on an exhaustive study of the world literature discuss frequency, diagnosis and treatment of this disease.

The actions of nitric oxide (NO) in the pathology of solid tumours are complicated and many are poorly understood because NO has both inhibitory and tumour-promoting activities. In the current study we aimed to find out immunohistochemically whether the expression of both the inducible (iNOS) and endothelial (eNOS) forms of the enzyme nitric oxide synthase (NOS) were changed in pleomorphic adenomas of the parotid compared with normal salivary tissue. There was a significant difference in staining for iNOS between the tumour and normal salivary tissue, with tumour epithelial cells being stained in 29 cases of the 30 cases studied (P< 0.0001). The luminal cells of the salivary ducts also stained, but not the normal salivary tissue. Immunohistochemistry for the eNOS isoenzyme showed moderate staining of the tumour epithelium in only three specimens. There was also mild staining in the salivary duct cells of the normal glandular tissue and in endothelium of blood vessels in both tumour and normal glandular tissue in the same 29 cases., (Copyright 2000 The British Association of Oral and Maxillofacial Surgeons.)

The parapharyngeal space is a deep neck region and can be the site of a wide range of neoplasms, including primary benign or malignant tumors, metastatic tumors, neoplasms invading the parapharyngeal space from the adjacent regions and neoformations stemming from systemic processes. Tumors of the parapharyngeal space are, nevertheless, relatively rare and account for 0.5-0.8% of all head and neck tumors. Most are benign tumors originating in the deep lobe of the parotid gland and the minor salivary glands. The most frequent tumor is pleomorphic adenoma while myoepithelioma accounts for just 1% of all salivary gland tumors. The present case report involves a case of myoepithelioma of the deep parotid gland lobe, arising in the parapharyngeal space. Together with a review of the literature, considerations are presented on the clinical and radiological evaluation, differential diagnosis and treatment of these lesions.