Spontaneous cutaneous-parotid fistula of the cheek caused by sialolithiasis in a child: a case report.

INTRODUCTION: Cheek fistulas of salivary origin in children are very rare, predominantly of congenital or traumatic origin but rarely caused by parotid sialolithiasis given its low prevalence in paediatric populations. CASE PRESENTATION: A 3-year-old child with no history other than substantial left-cheek swelling for 2 months was referred. We identified a cutaneous fistula with seropurulent discharge. At this time, we only observed mild inflammation of the left parotid duct papilla with no visible calculi. A first ultrasound scan only detected acute inflammation of the parotid duct that was treated with antibiotics. The discharge subsided but the fistula persisted. Two more episodes of infection occurred at 6-month intervals that were both treated by antibiotics. After this second treatment, a second ultrasound scan showed dilatation of the left parotid duct upstream of the cheek fistula with the presence of a calcification. We performed sialoendoscopy under general anaesthesia 10 days later. Before introduction of the sialoendoscope, we noticed a whitish calculus within the papilla that was removed by intraoral incision and digital pressure alone. Sialoendoscopy went on to detect a dilated parotid duct that was highly inflamed and bled upon contact at the site of the cheek fistula. No other sialoliths were detected. The fistula had healed four months later without any recurrence of parotitis or discharge. CONCLUSION: Sialolithiasis should be considered for spontaneous cheek fistulas in children. Sialoendoscopic-assisted diagnosis and treatment can result in complete resolution of cutaneous-parotid fistulas without the need for more aggressive surgery.

Ultrasound-guided thread lifting for the prevention of parotid gland and diagnosing parotid duct complications.

BACKGROUND: Thread lifting is a common minimally invasive plastic surgery procedure. Parotid gland injury caused by thread lifting is a known complication; however, visual evidence of this complication is lacking. OBJECTIVES: This study aimed to present cases of parotid gland injury by thread lifting shown using ultrasound and to discuss the importance of ultrasound detection of the location of the parotid gland before thread insertion. METHODS: This study included eight patients diagnosed with parotid gland perforation and one with parotid duct injury due to threads from November 2020 to October 2022. RESULTS: Six patients showed tenderness and swelling, three were asymptomatic, and one with duct injury showed severe swelling and pain. Although the severity and duration of symptoms have differed, we confirmed the progress of improvement with conservative treatment and confirmed ultrasound findings progressed. CONCLUSIONS: Using ultrasound to detect the parotid gland's location before thread lifting might reduce the chance of parotid duct injury. Identifying immediate parotid duct or gland injury with ultrasound can help to act quickly for delayed pain or swelling and reduce the likelihood of additional complications.

Eye removal following parotid duct transposition surgery: A survey of current practice among veterinary ophthalmologists.

OBJECTIVE: Identify dogs that required removal of an eye that had previously undergone a parotid duct transposition (PDT) and secondly to characterize demographics, surgical technique, and outcomes associated with it. PROCEDURE: An online survey was distributed to American College of Veterinary Ophthalmologists (ACVO) and Veterinary Ophthalmology (VOPH) listservs asking members to report the breed, reason for eye removal, time between surgeries, surgical technique, complications, and additional therapy instituted for dogs requiring removal of an eye subsequent to PDT surgery. RESULTS: Sixteen dogs fit the inclusion criteria. Small breeds (<15 kg) made up 80% of the study population. Time between surgeries was <6 months (1/16), 6 to 12 months (7/16), and ≥1 year (8/16). Reasons for eye removal included: advancing corneal disease (6/16), discomfort (6/16), reaction to saliva (4/16), decreased saliva production (2/16), glaucoma (1/16), orbital neoplasia (1/16), and endophthalmitis (1/16). Surgical techniques included: transection of the parotid duct without ligation (2/16), ligation (9/16), and reversal of the PDT with reimplantation into the mouth (5/16). Complications reported were two dogs who underwent duct ligation experienced prolonged dilation of the duct that resolved with medical therapy (1/2) or without additional therapy (1/2). CONCLUSION: Ligation of or reversal of the PDT with reimplantation into the mouth are appropriate adjunctive surgical techniques when removing an eye that previously underwent PDT surgery. Two dogs with nonfunctional PDT had complication-free eye removal with transection without ligation. Prolonged dilation of the duct is possible after eye removal with duct ligation and may resolve with time or medical management.

[Evaluation of the Normal Structures of Parotid Duct Using Magnetic Resonance Hydrography].

Objective To investigate the normal structures of parotid duct by using magnetic resonance(MR)hydrography. Methods MR three-dimensional heavy T2-weighted imaging was performed in 21 normal subjects.After taking 200 mg of vitamin C orally for 3 minutes,the subjects underwent parotid duct coronal hydro-magnetic resonance imaging.The images were transferred to the GE AW4.5 workstation,on which multi-planner reformation was performed using Functool software.The numbers of the parotid duct,accessory parotid duct,segments,and its branches was counted and the length and diameter of the intra-and extra-parotid ducts were measured. Results Accessory ducts were found in 24 parotid glands(57.1%,24/42),with the average length being(9.54±9.98)mm and the average diameter being(0.87±0.88)mm.The intra-parotid ducts were found to be with 3 segments were in 3 cases(7.14%,3/42),with 2 segments in 19 cases(45.23%,19/42),and with 1 segment in 20 cases(47.62%,20/42).The average number of the branches of the first,second and third segment was 2.38,0.88,and 0.1,respectively.The average length of the intra-parotid duct was(36.97±7.97)mm,with its average diameter being(2.01±0.76)mm.The average length of extra-parotid duct was(34.98±10.25)mm,with its average diameter being(2.13±0.79)mm.The average length of the whole parotid duct was(71.95±11.47)mm,with its average diameter being(2.07±0.68)mm. Conclusion The parotid duct,the accessory parotid duct,and the segments and their branches of the intra-parotid duct can be accurately displayed by MR hydrography.

Enucleation or exenteration in two dogs with previous parotid duct transposition: parotid duct ligation versus reverse parotid duct transposition.

Two dogs with previous parotid duct transpositions presented with unrelated ocular disease. In both cases, ophthalmic examination revealed the need for enucleation or exenteration. In case 1, systemic coccidioidomycosis was diagnosed with panuveitis and secondary glaucoma of the left eye. In this case, the parotid duct was ligated at the time of enucleation to stop salivary secretions. This dog encountered morbidity in the form of a sialocele that did not resolve for 11 months. In case 2, ultrasound and computed tomography revealed a discrete mass within the left medial orbit that was suspected to arise from the nictitating membrane. A combination of exenteration and parotid duct transposition reversal was performed to avoid morbidity associated with ligation of the parotid duct. The dog encountered no complications from this novel procedure. This case report represents the first report of re-routing a transposed parotid duct from the ventral conjunctival sac back to the mouth at the time of enucleation or exenteration in the dog.

Computational modeling of epithelial fluid and ion transport in the parotid duct after transfection of human aquaporin-1.

Previous studies have shown that localized delivery of the aquaporin-1 (AQP1) gene to the parotid duct can restore saliva flow in minipigs following irradiation-induced salivary hypofunction. The resulting flow rate and electrochemistry of secreted saliva contradicts current understanding of ductal fluid transport. We hypothesized that changes in expression of ion transport proteins have occurred following AQP1 transfection. We use a mathematical model of ion and fluid transport across the parotid duct epithelial cells to predict the expression profile of ion transporters that are consistent with the experimental measurements of saliva composition and secretion rates. Using a baseline set of parameters, the model reproduces the data for the irradiated, non-AQP1-transfected case. We propose three scenarios which may have occurred after transfection, which differ in the location of the AQP1 gene. The first scenario places AQP1 within nonsecretory cells, and requires that epithelial sodium channel (ENaC) expression is greatly reduced (1.3% of baseline), and ductal bicarbonate concentration is increased from 40.6 to 137.0 mM, to drive water secretion into the duct. The second scenario introduces the AQP1 gene into all ductal cells. The final scenario has AQP1 primarily in the proximal duct cells which secrete water under baseline conditions. We find the change in the remaining cells includes a 95.8% reduction in ENaC expression, enabling us to reproduce all experimental ionic concentrations within 9 mM. These findings provide a mechanistic basis for the observations and will guide the further development of gene transfer therapy for salivary hypofunction. NEW & NOTEWORTHY: Following transfection of aquaporin into the parotid ducts of minipigs with salivary hypofunction, the resulting increase in salivary flow rates contradicts current understanding of ductal fluid transport. We show that the change in saliva electrochemistry and flow rate can be explained by changes in expression of ion transporters in the ductal cell membranes, using a mathematical model replicating a single parotid duct.

Surface anatomy of the parotid duct and its clinical relevance.

The trajectory of the parotid duct (PD) makes it vulnerable to injuries during facial trauma and facial rejuvenation procedures. The PD is usually represented as a straight line, although its description in the literature varies. Our objective was to study the trajectory of the PD and to define reliable cutaneous landmarks. We dissected 35 human cadaver half-heads. We defined three points: point I where the PD crossed a line (line 2) between point T (the intertragal incisura) and point C (the corner of the mouth), point S for the top of the PD, and point B where the PD penetrated the buccinator muscle. We measured the distance (D) between points T and C, the distance (d1) between points T and I, and the distance (d2) between points T and B. We also determined the height (h) of the orthogonal line between point S and line 2. We noted that for all of the half-heads that we examined, the PD followed a curved trajectory between points I and B above line 2. Point I was located 1/3 of the way along distance D. Point B was tangential to line 2, and was located 2/3 of the way along distance D. The average height measurement (h) was 1.4 cm. We demonstrated that the PD follows a curved trajectory from the 1/3 mark to the 2/3 mark along distance D, the top of this curve being 1.5 cm above the line TC.

Histological and chemical view on parotid duct sialolithiasis in the Slovakian warmblood mare.

The parotid duct has been reported to be the most common site of sialoliths in horses. In this case report, we described the first confirmed case of the equine sialolithiasis in Slovakia. The work was aimed to describe the transcutaneous approach to removing the sialolith, which manifested as a hard painless mass in the area of the maxillary cheek teeth, in a 14-year-old Slovakian warmblood mare. Pathological-anatomical and histological examination after extirpation confirmed the presence of parotid duct ectasia resulting from calculus. The mineral composition of the sialolith was determined with atomic absorption spectroscopy using X-ray powder diffraction. The sialolith was successfully extirpated transcutaneously, without complications or recurrence.

Case report: Sepsis secondary to infected protracted parotid sialocele after maxillofacial oncologic surgery in a dog.

An 8-year-old male intact mixed breed dog was treated for a 3.7×3×3.6 cm grade 1 multilobular osteochondrosarcoma (MLO) arising from the dorsal aspect of the right coronoid process with a coronoidectomy, a zygomectomy, and a caudal maxillectomy. Ten months later, the dog presented for a swelling near the right angular process, which was presumed to be a locoregional recurrence. Blood work and initial staging tests (abdominal ultrasound) had mild abnormalities of no clinical concern/significance. The dog was hospitalized with a plan for computed tomographic (CT) scan of skull and chest the following day. Overnight, the swelling rapidly increased, and the dog became laterally recumbent, febrile, and hypotensive. Laboratory evaluation revealed hypoglycemia, elevated lactate, and elevated band neutrophils with moderate toxicity, most consistent with sepsis. The dog was stabilized with fluid resuscitation, intravenous (IV) antibiotics, IV dextrose, and pressor support. Once stabilized, a contrast CT scan was performed, which revealed evidence of an infected parotid gland sialocele. To our knowledge, this is the first veterinary case that describes sepsis secondary to an infected protracted parotid sialocele.

Effect of dose to parotid ducts on Sticky Saliva and Xerostomia in radiotherapy of head and neck squamous cell carcinoma.

BACKGROUND: Radiotherapy (RT) in head and neck squamous cell cancer (HNSCC) often leads to sticky saliva and xerostomia (SSX). Dose sparing of salivary glands (SG) reduces occurrence of SSX but few studies investigated the relationship between RT dose to SG substructures and SSX. We therefore investigated this hypothesis, focusing on the parotid duct (PD). METHODS: Retrospective data was collected from 99 HNSCC patients treated at our center with (chemo-)radiotherapy (CRT). PD and other organs-at-risk (OAR) were (re-)contoured and DVHs were generated without re-planning. SSX was graded according to CTCAE v.4.03 and evaluated at acute, subacute, and two late timepoints. RESULTS: Most patients presented with loco-regionally advanced disease. In 47% of patients, up-front neck dissection preceded CRT. Weighted mean dose was 28.6 Gy for bilateral parotid glands (PG), and 32.0 Gy for PD. Acute SSX presented as grades 0 (35.3%), I (41.4%), II (21.2%) and III (2.0%). There was no association of OARs and SSX ≥ grade 2 in univariable logistic regression (LR). Multivariable LR showed statistically significant relationship of acute SSX with: PG weighted mean dose (OR 0.84, p = 0.004), contralateral PG mean dose (OR 1.14, p = 0.02) and contralateral PD planning OAR (PD PRV) mean dose (OR 1.84, p = 0.03). CONCLUSIONS: There was an association of acute SSX with dose exposure of PD PRV in multivariable regression, only. Due to statistical uncertainties and the retrospective nature of this analysis, further studies are required to confirm or reject the hypothesis.

Bilateral parotid duct transposition for keratoconjunctivitis sicca in a Connemara stallion.

A 7-year-old Connemara stallion was presented with a 4 month history of blepharospasm, recurrent corneal ulcerations, mucopurulent ocular discharge, and keratoconjunctivitis sicca (KCS) in both eyes unresponsive to medical therapy. Ophthalmic examination revealed lackluster corneas, axial corneal scarring and pigmentation with associated neovascularization, and absolute KCS in both eyes. Computed tomography scan and endoscopic evaluation of the upper airway and guttural pouches revealed no structural abnormalities to indicate neurogenic KCS. The stallion was diagnosed with immune-mediated dacryoadenitis as all other causes of KCS were excluded. Parotid duct transposition (PDT) was performed in the right eye followed by PDT in the left eye 4 weeks later. The right PDT was functional 2 years post-operatively with significant improvement in ocular comfort and reduced corneal fibrosis and neovascularization. The left PDT developed a salivary-cutaneous fistula over the left masseter muscle post-operatively due to avascular necrosis of the distal parotid duct (PD). Surgical reconstruction of the PDT using an expanded-polytetrafluoroethylene (e-PTFE) tube graft, an e-PTFE tube graft to autogenous caudal auricular vein graft, and an autogenous saphenous vein graft were all unsuccessful. Tear production in the left eye improved at 1 year post-surgery as a result of long term lacrostimulant therapy, and a permanent PD-cutaneous fistula was performed on the left PD at the level of the ventral mandible. Bilateral PDT in the horse is effective in resolving clinical signs associated with KCS; however, morbidity associated with avascular necrosis of the transposed PD may be significant and can result in surgical failure.

Traumatic Injuries of the Parotid Gland and Duct.

This review will focus on the key steps in the recognition of parotid gland and duct injuries focusing on the important steps needed at the initial assessment. Management planning is presented in the way that trauma surgeons interact with patients, highlighting the important parts of the informed consent conversation followed by the key information that must be communicated to the anesthesia and operating room teams, which ensures proper monitoring and equipment needs are in place. Short-term and long-term outcomes for patients with persistent sequelae of the trauma and their management are reviewed.

Rhinosporidiosis of Parotid Duct: A Report of Five Case Series.

Rhinosporidiosis of the parotid duct is extremely rare. The sporadic cases of rhinosporidiosis are seen all over the world but more than 90% of the cases are reported from South Asia and Brazil. We report five male patients with parotid duct rhinosporidiosis ranging from eighteen to seventy-two years of age, hailing from the eastern part of India. All of them presented with right parotid swelling. Clinical examination revealed cystic swelling. Imaging studies of these patients suggested sialocele and abscess. Cytology was non-diagnostic. All five patients underwent complete surgical excision of the cyst. Histopathological examination of cysts confirmed the diagnosis of rhinosporidosis of the parotid duct. Regular follow-up was done and all were disease-free even after five years of follow-up.There is a need for a high index of suspicion of parotid swelling of this nature in endemic areas.

Precise localization of parotid duct: a cadaveric study.

This study aimed to determine the precise localization and course of parotid duct based on morphometric data obtained by measurements regarding several superficial landmarks and lines. Totally, 46 parotid ducts of 24 formalin-fixed adult amputated heads (12 female and 12 male) aged between 45 and 92 years, present in the collection of Anatomy Department, School of Medicine, Mersin University, were evaluated. First, three reference lines were defined: L1: between intertragic notch and labial commissure, L2: between intertragic notch and nasal wing, and L3: between intertragic notch and lateral palpebral commissure. The location of the parotid duct with respect to these lines were recorded. In all sides, parotid duct was detected in the middle 1/3 of L1. In 71.7% of all hemifaces, the parotid duct was making an upward curve around L1. Its proximal end exiting from the anterior border of the parotid gland was 12.34 ± 28.83 mm below the proximal 1/3 point of L1. Then, it was crossing L1 at a point with a mean distance of 53.90 ± 9.69 mm from the labial commissure where it is almost at L1 midpoint. Its distal end was located 9.61 ± 2.88 mm above the distal 1/3 point of L1. In 21.7% of all hemifaces, PD was observed totally above L1, while the shortest distances of its proximal and distal ends to L1 were 4.35 ± 2.45 mm and 13.17 ± 4.52 mm, respectively. In 6.5% of all hemifaces, its proximal end was located just on L1, coursing upwards and terminating 11.76 ± 2.53 mm above L1.

Anatomical Features of the Parotid Duct in Sialography as an Aid to Endoscopy-A Retrospective Study.

Sialography is used for diagnosis of obstructive salivary gland diseases and prior to sialendoscopy. Three-dimensional cone beam computerized tomography (CBCT) sialography allows imaging and measurement of salivary duct structures. Salivary gland endoscopy has a long learning curve. The aim of this retrospective study is to create an anatomical quantitative guide of different distances and angles significant for endoscopy. Twenty-six CBCT sialographies of healthy parotid ducts were included. Outcome parameters included diameters, distances, angles and number of minor tributaries. Results show the average distance from the papilla to the curvature of the gland was 41.5 mm (Q1 36.97 mm-Q3 45.32 mm), with an angle of 126.9° (Q1 107.58°-Q3 135.6°) of the curvature and a distance of 35.25 mm (±7.81 mm) between the curvature and the hilus. The mean width of the duct was 0.8 mm (Q1 0.7 mm-Q3 1.15 mm) at its narrowest and 2 mm (Q1 1.4 mm-Q3 2.2 mm) at its widest. This is the first anatomical quantitative study of the parotid duct in relation to sialendoscopy.

DICER1-Mutated Botryoid Fibroepithelial Polyp of the Parotid Duct: Report of the First Case.

DICER1, a member of the ribonuclease III family, is involved in the biogenesis of microRNAs and, hence, it influences gene expression regulation. DICER1 germline (associated with the inherited DICER1 syndrome) or somatic mutations have been linked to tumorigenesis in histogenetically diverse benign and malignant neoplasms in different organs including pleuropulmonary blastoma, cystic nephroma, embryonal rhabdomyosarcoma, nasal chondromesenchymal hamartoma, poorly differentiated thyroid carcinoma, thyroblastoma, intracranial sarcoma and gonadal Sertoli-Leydig cell tumors in addition to others. Moreover, rare botryoid (giant) fibroepithelial polyps may harbor this mutation. Herein, we describe the first reported case of a DICER1-mutated botryoid fibroepithelial polyp occurring within the parotid duct of a 65-year-old female who has no other features or family history of the DICER1 syndrome. Based on its distinctive morphology, we tested this lesion specifically for DICER1 mutations and confirmed the presence of a pathogenic DICER1 variant with a low allele frequency, consistent with a somatic mutation.

Management of Traumatic Soft Tissue Injuries of the Face.

Facial soft tissue injuries encompass a broad spectrum of presentations and often present significant challenges to the craniofacial surgeon. A thorough and systematic approach to these patients is critical to ensure that the patient is stabilized, other injuries identified, and the full extent of the injuries are assessed. Initial management focuses on wound cleaning with irrigation, hemostasis, and debridement of nonviable tissue. Definitive management is dependent on the region of the face involved with special considerations for critical structures such as the globe, lacrimal apparatus, facial nerve, and parotid duct. Following sound surgical principles, these injuries can be managed to maximize both functional and aesthetic outcomes while minimizing complications.

Reconstruction of parotid duct defect with autologous vein graft and vascular coupler after buccal mucosa cancer resection.

The distal end of parotid duct is often inevitably resected en-block with the buccal mucosa cancer to obtain safety margin and prevent local recurrence. Ligation of duct frequently causes complications like cheek swelling, fistula and gland function loss. The authors describe a novel procedure of combined use of autologous vein graft and vascular coupler to reconstruct the parotid duct defect for buccal mucosa cancer patients who undergo radical neck dissection and free-flap reconstruction, no lumen-stent or cannula is needed. Case examples are shown to illustrate the operative details and different outcomes for two kinds of orifice site choices. Key factors for success include the proper use of Coupler device, right choice of new orifice location and maintenance of lumen patency. For buccal mucosa cancer patients, this novel method for parotid duct reconstruction could effectively reduce postoperative complications and preserve the parotid gland function.

Submandibular excision with and without parotid duct ligation for sialorrhoea.

In this case series with retrospective review we compared the outcomes of patients with sialorrhoea who had a submandibular excision (SE) alone and those who had submandibular excision with parotid duct ligation (SE + PL) between 2012 and 2018. Primary endpoints of complication rates and caregivers' perceptions of success were collected. A total of 41 submandibular excisions were performed for sialorrhoea (26 patients underwent SE, while 15 underwent SE + PL). Significant differences in the groups existed at baseline with patients in the SE plus PL group being more likely to have a tracheostomy (p = 0.015), to use sublingual atropine (p = 0.038) and respiratory medications (albuterol p = 0.0075, gentamicin p = 0.018), to have more pneumonias six months prior to the procedure (p < 0.001), and more hospitalisations six months prior to the procedure (p = 0.046). More postoperative surgical site complications were associated with ligation (p = 0.012). There was no difference in systemic infection (p = 0.25), and no difference in caregivers' perceptions of success in reducing sialorrhoea (18/24 SE compared with 10/14 SE + PL, p = 1.00). There were more surgical site complications in those undergoing SE plus PL than in those who had SE alone. Given this data, parotid duct ligation may not yield additional benefit when combined with submandibular excision.

Surgical Management of Parotid Duct Injury Using a Feeding Tube.

The parotid duct (Stenson's duct) can be damaged during traumatic injuries and surgical interventions. Early diagnosis and treatment of a duct injury is of great importance because complications such as sialocele and salivary gland fistula may develop if the duct is not surgically repaired. We think that the feeding tube is an ideal material in the parotid duct repair because of its technical characteristics, availability, and low cost. In this article, we described the use of a feeding tube for the treatment of a parotid duct rupture in a facial stab wound laceration, as it is a low-cost and easy-to-access material readily available in every operating room.