Posture-based Morphological Deformation of the Parotid Gland and its Clinical Implications for Minimally Invasive Procedures

Anatomical studies of the parotid gland are important for mid- and lower face filler, botulinum toxin, and thread lifting procedures. The purpose of this study was to observe the topographic anatomy of the parotid gland using cadaveric dissections. The superficial lobe of the parotid gland was studied in 30 hemisected heads. Reference lines were made on the lateral aspect of the face. A reference line (the line connecting the mandibular angle to the upper margin of the zygomatic arch, along the posterior margin of the ramus) was divided into four sections (P1, P2, P3, and P4). The superior, inferior, anterior, and posterior borders of the parotid gland were measured using the reference lines and sections. Using these measurements, we categorized the superficial lobe of the parotid gland into two types: type Ia, pistol-shaped; Ib, pistol-shaped with an accessory lobe; and type II, oval-shaped. The superior border of the parotid gland started just below the inferior margin of the zygomatic arch. The parotid gland covered the posterior part of the masseter muscle near P1 and P2, but at P3 and below P3, the tail of the parotid gland was located posterior to the ramus and covered the anterior part of the sternocleidomastoid muscle. The topographic anatomy of the parotid gland serves as a reliable reference for esthetic procedures in the lower face and neck region.

Prevalence and Clinical Implications of Incidentally Detected Parotid Lesions as Blind Spot on Brain MRI: A Single-Center Experience

Background and objective: This study was conducted to assess the prevalence and clinical implications of parotid lesions detected incidentally during brain magnetic resonance imaging (MRI) examination. Materials and Methods: Between February 2016 and February 2021, we identified 86 lesions in the brain MRI reports of 84 patients that contained the words “parotid gland” or “PG”. Of these, we finally included 49 lesions involving 45 patients following histopathological confirmation. Results: Based on the laboratory, radiological or histopathological findings, the prevalence of incidental parotid lesions was low (1.2%). Among the 45 study patients, 41 (91.1%) had unilateral lesions, and the majority of the lesions were located in the superficial lobe (40/49, 81.6%). The mean size of the parotid lesions was 1.3 cm ± 0.4 cm (range, 0.5 cm–2.8 cm). Of these, 46 parotid lesions (93.9%) were benign, whereas the remaining three lesions were malignant (6.1%). Conclusions: Despite the low prevalence and incidence of malignancy associated with incidental parotid lesions detected on brain MRI, the clinical implications are potentially significant. Therefore, clinical awareness and appropriate imaging work-up of these lesions are important for accurate diagnosis and timely management.

A Rare Case of Paediatric Pleomorphic Adenoma of the Parotid Gland

Pleomorphic adenomas are benign salivary gland tumours, which predominantly affect the superficial lobe of the parotid gland. The “pleomorphic” nature of the tumour can be explained on the basis of its epithelial and connective tissue origin. The tumour has a female predilection between 30-50 years of age. Slowly progressing asymptomatic swelling is the usual presentation of the tumour. Surgical excision of the tumour mass forms the mainstay of treatment, with utmost care taken to preserve the facial nerve. This case report aims to throw light on an interesting case of pleomorphic adenoma of the parotid gland in a 10 years old female patient. The patient presented with a slowly progressing asymptomatic swelling on the right side of the face, which was diagnosed to be pleomorphic adenoma of right parotid gland. The aim of the study is to discuss how to proceed regarding the further management.

The Clinical Characteristics and CT Findings of Parotid and Submandibular Gland Tumours

Objective. To investigate the clinical characteristics and CT findings of parotid and submandibular gland tumours. Materials and methods. From May 2017 to April 2020, all patients with clinically proven parotid and submandibular gland enlargement and palpable masses underwent CT examinations. All patients were confirmed by pathology after surgery. The clinical characteristics and CT features were observed and evaluated. The mean density values before and after enhancement were measured and analyzed. The chi-square test, one-way ANOVA, and Student's t-test were used. Results. Ninety-four patients with a total of 94 unilateral tumours in the parotid and submandibular glands were enrolled, including 38 pleomorphic adenomas (PAs), 27 Warthin’s tumours (WTs), and 29 malignant tumours (MTs). The majority of the PAs (28/38) and MTs (23/29) were located in the parotid gland; the others were located in the submandibular gland. All the WTs were in the parotid gland. The most common benign tumours of the parotid gland were PAs (28/38, 73.7%) and WTs (27/27, 100%), and the most common MTs were mucoepidermoid carcinoma, acinic cell carcinoma, and squamous cell carcinoma (4/29, 13.8%). The most common benign and malignant tumours in the submandibular gland were PAs (10/38, 26.3%) and ductal adenocarcinomas (3/4, 75%). The majority of PA patients (28/38) were female, compared with WT (2/27) ( P < 0.001 ) and malignant tumour patients (10/29) ( P < 0.01 ). A significant difference was also found between WTs and MTs in female patients ( P < 0.05 ). The mean age of PA patients was 43.4 ± 12.1 years, which was lower than that of WTs (62.1 ± 11.7) and MTs (58 ± 14.18) ( P < 0.001 , P < 0.001 , and P = 0.244 , respectively). On CT imaging, the mean diameter of the PAs and WTs was significantly smaller than that of the MTs ( P = 0.001 and P < 0.001 ), and no difference was observed between the PAs and WTs ( P = 0.275 ). In the parotid gland, the superficial lobe was more frequently involved than the deep lobe (PAs, 22 : 6; WTs, 17 : 10; and MTs, 15 : 8). The majority of PAs and WTs demonstrated round shapes (25/38, 19/27) and were well defined (30/38, 24/27); by contrast, most MTs were lobulated, irregular shapes (24/29), and ill defined (25/29). On plain CT, the PAs were usually homogeneous, while MTs were frequently heterogeneous, with more necrosis, larger cystic areas, and more haemorrhage or calcification. The mean CT values of PAs, WTs, and MTs were 39.2 ± 3.9 HU, 39.1 ± 3.0 HU, and 37.6 ± 3.1 HU ( P > 0.05 ), respectively. On contrast CT, the WTs were significantly enhanced compared with MTs and PAs, with mean CT values of 53.5 ± 4.0 HU, 84.4 ± 6.0 HU, and 65.2 ± 3.8 HU, respectively (all P < 0.001 ). The mean CT value changes for PAs, WTs, and MTs (∆) were 14.4 ± 3.0 HU, 45.3 ± 4.5 HU, and 27.7 ± 2.5 HU, respectively. Significant differences were observed between ∆PAs and ∆WTs, ∆PAs and ∆MTs, and ∆WTs and ∆MTs (all P < 0.001 ). Conclusion. Parotid and submandibular gland tumours have some typical clinical characteristics and CT findings, and plain and early contrast-phase CT combined with clinical parameters may be helpful for diagnosis.

Unusual presentation of a first branchial arch fistula with maxillofacial infection: a case report

Background First branchial cleft anomaly (FBCA) is a rare congenital defect that arises due to incomplete closure of the ventral portion of the first and second branchial arches. There are variable complex clinical manifestations for patients with FBCA, which are prone to misdiagnosis and inadequate treatment. FBCAs usually involve the facial nerve with a consequent increased risk of facial nerve damage. Here, we present an unusual case of FBCA presenting with two preauricular pits in association with an abnormal maxillofacial cyst. Case presentation A 10-month-old girl presented to our department due to recurrent maxillofacial infections accompanied by swelling or abscess of the left cheek and purulent discharge from the preauricular pit for 4 months. A 3D-computed tomography (CT) fistulogram and magnetic resonance imaging (MRI) revealed two conjunctive tract lesions: one tract arose from the skin surface anteroinferior to the external auditory canal (EAC), through the deep lobe of the left parotid, and anteriorly extended to the left masseter; the other extended from the superficial lobe of the left parotid to the intertragic notch. After the maxillofacial infection was controlled by intravenous antibiotic administration, surgery was performed. Intraoperative tools, such as facial nerve monitors, microscopes, and methylene blue dyes, were used to facilitate the complete dissection and protection of the facial nerve. On follow-up over one year, the patient recovered well without facial palsy or recurrence. Conclusion FBCA with maxillofacial cysts is rare and prone to misdiagnosis. Physicians should pay attention to this anatomic variant of FBCA with the fistula track located deep inside the facial nerve and projected medially to the masseter.

Pleomorphic Adenoma of Three Different Sites: a Consecutive Case Series

Background: Pleomorphic adenomas are benign salivary gland tumors predominantly arising from the superficial lobe of the parotid gland and rarely from the small salivary glands located at various locations including parotid, lacrimal duct, lip, floor of the mouth etc. Surgical excision of the tumor mass is the treatment of choice with utmost care taken to preserve the facial nerve in cases involving the parotid gland. Case details: This case series highlights three consecutive cases of pleomorphic adenoma arising from three different locations. Conclusion: Pleomorphic adenoma is the commonest salivary gland tumor characterized by diverse histomorphological features and can occur at any site where salivary tissue is present. Careful histopathological analysis should be done in all tumors arising especially in the head and neck region.

Complications of Parotid surgery: A study in 60 cases

Objective: To evaluate the common complications following parotid surgery. Material & methods: A retrospective study was done from January 2011 to December 2019 in the Department of ENT & Head Neck Surgery, Enam Medical College & hospital, Savar. Sixty (60) patients with both benign & malignant parotid disease underwent surgical treatment was selected for this study. All cases were diagnosed preoperatively by Fine Needle Aspiration Cytology (FNAC). Patients with preoperative facial nerve palsy were excluded from this study. Patients were followed up for six months and per operative & postoperative complications were evaluated. Results: Out of 60 patients, superficial parotidectomy was done in52 (86.67%) patients and total conservative parotidectomy was done in 08 (13.33%) patients. In this study 56 cases were benign and 04 cases were malignant. Among this 41 (68.33%) pleomorphic adenoma, 05 (8.33%) warthin’s tumour, 03 (5%) benign lymphoepithelial cyst, 03(5%) haemangioma, 02(3.33) sialocele, 01(1.67) dermoid and 01 (1.67%) had salivary fistula. All 04(6.67%) malignant cases were diagnosed as mucoepidermoid carcinoma. Majority of pleomorphic adenomas (92.68%) involved the superficial lobe of the gland. Most commonly observed post operative complication was facial nerve paresis (05%), but only 1.67% developed permanent palsy. Others complication includes Hypoesthesia of the greater auricular nerve (05%), Frey’s syndrome (3.33%) & wound infection (3.33%). Conclusion: Facial nerve palsy is the frequent complication after parotid surgery in this study. Surgeons have to pay attention to minimize the risk of complication during parotidectomy. However, this operation continues to be a challenge on account of the wide range of tumours encountered and the variations in size and location and the facial nerve preservation. Bangladesh J Otorhinolaryngol; April 2021; 27(1): 59-65

Deep Lobe Parotid Tumors: A Systematic Review and Meta-analysis

Objective We performed a systematic review and meta-analysis of deep lobe parotid tumors to evaluate their unique characteristics. Data Sources PubMed/Medline, Embase, Web of Sciences, and Cochrane Library databases were queried for relevant literature. Review Methods Studies were individually assessed by 2 independent reviewers. Risk of bias was assessed with the Cochrane bias tool, GRADE criteria, and MINORS criteria. Results were reported according to the PRISMA guidelines. Statistical analysis was performed by comparing rates of malignancy between deep and superficial lobe tumors. Results In total, 8 studies including 379 deep lobe parotid tumors met inclusion criteria. Mean age at diagnosis was 44.9 years. Computed tomography scan was the most common imaging modality. Preoperative diagnostic fine-needle aspiration was utilized in 39.4% of patients and demonstrated high sensitivity for malignant disease. The most common approach was subtotal parotidectomy with facial nerve preservation (58.9%). The rate of malignancy was 26.6%, which was significantly higher than that of the superficial lobe tumors in this study (risk ratio, 1.25; 95% CI, 1.01-1.56). The rate of temporary postoperative facial nerve weakness between deep and superficial lobe tumors was 32.5% and 11.7%, respectively. Conclusion Deep lobe parotid tumors had a 26.6% rate of malignancy. On meta-analysis, deep lobe tumors appeared to have higher rates of malignancy than superficial lobe tumors. Surgical excision of deep lobe tumors showed increased rates of temporary facial nerve paresis as compared with superficial lobe tumors. Computed tomography scan was the most common imaging modality. There were limited data regarding the utility of fine-needle aspiration.

Dynamic Three-Dimensional ADC Changes of Parotid Glands During Radiotherapy Predict the Salivary Secretary Function in Patients With Head and Neck Squamous Carcinoma

ObjectiveTo investigate the changes of three-dimensional apparent diffusion coefficient (3D-ADC) of bilateral parotid glands during radiotherapy for head and neck squamous cell carcinoma (HNSCC) patients and explore the correlations with the radiation dose, volume reduction of parotid gland and the salivary secretary function.Materials and Methods60 HNSCC were retrospectively collected in Sichuan cancer hospital. The patients were all received diffusion-weighted imaging (DWI) scan at pre-radiation, the 15th radiation, the 25th radiation and completion of radiation. Dynamic 3D-ADC were measured in different lobes of parotid glands (P1: deep lobe of ipsilateral; P2: superficial lobe of ipsilateral; P3: deep lobe of contralateral; P4: superficial lobe of contralateral), and the 3D-ADC of spinal cord were also recorded. Chewing stimulates test, radionuclide scan and RTOG criteria were recorded to evaluate the salivary secretary function. Pearson analysis was used to assess the correlation between 3D-ADC value, radiation dose, volume change, and salivary secretary function.ResultsThe mean 3D-ADC of parotid glands increased. It began to change at the 15th radiation and the mostly increased in P1. However, there was no change for the maximum and minimum 3D-ADC. The 3D-ADC values of spinal cord changes were almost invisible (ratio ≤ 0.03 ± 0.01). The mean 3D-ADC was negatively correlated with the salivary secretary function (r=-0.72) and volume reduction of different lobes of parotid glands (r1=-0.64; r2=-0.61; r3=-0.57; r4=-0.49), but it was positively correlated with the delivered dose (r1 = 0.73; r2 = 0.69; r3 = 0.65; r4 = 0.78).ConclusionDynamic 3D-ADC changes might be a new and early indicator to predict and evaluate the secretary function of parotid glands during radiotherapy.