Imaging of the sublingual and submandibular spaces

Imaging of salivary gland cancers derived from a sublingual gland herniated into the submandibular space: a report of three cases

Sublingual gland herniation into the submandibular space through a mylohyoid muscle defect is a common anatomical variation; however, salivary gland cancers that arise from a herniated sublingual gland have not been described yet. Here, we report three patients with salivary gland cancers originating from a herniated sublingual gland. All tumors were detected as palpable submandibular masses, located anterior to the submandibular gland, medial to the mandible, and lateral to the mylohyoid muscle, with contact with the sublingual gland through a mylohyoid muscle defect. Intraoperative findings confirmed that the masses were derived from herniated sublingual glands. Pathological examination showed one case of mucoepidermoid carcinoma and two cases of adenoid cystic carcinoma. Imaging findings of the tumor location, in addition to the continuity with the sublingual gland through the mylohyoid muscle defect, are crucial for accurately diagnosing the tumor origin, which is essential for determining the appropriate clinical management.

Diagnostic Difficulties of Plunging Ranula: A Review of 18 Cases

OBJECTIVE(S)

Despite advancements in imaging techniques and cytological analysis, plunging ranula remains a challenging surgical, radiologic, and pathologic phenomenon. Of the 18 patients we evaluated at our institution, we highlight three cases that illustrate the high rate of misleading imaging and cytological results when assessing plunging ranula.

METHODS

Imaging results, biopsy findings, operative techniques, and pathological reports were reviewed from patients who had either a preoperative or postoperative diagnosis of ranula and underwent surgery by a single head and neck surgeon at a tertiary care center.

RESULTS

Of the 18 identified patients, computed tomography was correct on preoperative imaging 73% of the time and magnetic resonance imaging was correct on preoperative imaging 71% of the time. Two patients underwent preoperative ultrasound and their ultrasound reports did not accurately diagnose the presence of a ranula. Two patients underwent preoperative fine needle aspiration biopsy due to inconclusive preoperative imaging, in which results suggested either a ranula or epidermal cyst. Both ultimately did not match the final pathology. Three of eighteen patients (17%) underwent an inappropriate initial surgery due to incorrect imaging diagnoses and/or biopsy findings.

CONCLUSION

Despite use of preoperative modalities to distinguish plunging ranula from other cystic floor of mouth lesions, surgeons must be aware that no workup modality is fully precise. The potential for revision surgery must be included in all preoperative discussions for presumed plunging ranula.

LEVEL OF EVIDENCE

4 Laryngoscope, 134:2689-2696, 2024.

Multispace Maxillofacial Space Infections Involving Orbit: Report of a Rare Case

Peri-apical infection is a prevalent form of odontogenic infection, typically following the path of least resistance through cancellous bone towards the cortical plate. This infection begins as cellulitis and may progress to an abscess, sometimes involving various anatomically potential spaces. While frontal space infection is a rare complication of odontogenic infection spread, it can occur in conjunction with buccal space, sub-mental space, and orbital space involvement. In this report, we present the case of a 62-year-old man with a history of tooth pain and diabetes mellitus for the past decade. The patient exhibited symptoms of swelling, multiple draining sinuses, pain, proptosis, and fever. Prompt action was taken to drain the multiple abscesses, and the causative teeth were subsequently extracted. This case illustrates one of the severe complications associated with odontogenic infection, which has the potential to be life-threatening.

Mylohyoid Muscle: Current Understanding for Clinical Management Part II: Clinical Anatomy, Radiology, and Surgical/Clinical Relevance

The mylohyoid is one of the suprahyoid muscles along with the geniohyoid, digastric, and stylohyoid muscles that lies between the anterior belly of the digastric muscle inferiorly and the geniohyoid superiorly. In Part II, the radiology and clinical/surgical importance of the mylohyoid muscle will be discussed.

Imaging evaluation of the benign and malignant lesions of the floor of the mouth: Pictorial review

The floor of the mouth is an important anatomical region of the oral cavity where primary benign and malignant disease processes can originate or secondary pathologies can extend into adjacent spaces. Knowledge of the anatomy is crucial for accurate localisation of pathology and understanding the spread of disease. The sublingual space is the dominant component of the floor of the mouth, bounded inferiorly by the mylohyoid muscle that separates it from the submandibular space. Imaging is immensely important to characterise and map the extent of disease, considering the fact that the bulk of the disease may be submucosal and not visible on clinical inspection.

Contribution

The floor of the mouth is a complex anatomical region for radiological evaluation. The purpose of this pictorial review is to present an understanding of the relevant anatomy and to demonstrate the role and appropriate application of different imaging modalities. This article highlights the imaging spectrum of a wide range of various benign conditions including normal variants and a variety of malignant lesions at different tumour stages, with an aim to establish the correct diagnosis, avoid misinterpretation and help in treatment planning.

Characteristic imaging findings in a patient with chronic expanding hematoma on the floor of the mouth

Chronic expanding hematoma (CEH) is defined as chronic hematoma enlargement for more than 1 month. Although CEH rarely occurs on the floor of the mouth, the need to distinguish these cases from malignant disease is critical, given the need for potentially extensive resection in patients with malignancy. We report a case of CEH on the floor of the mouth, which required differentiation from malignant tumor. A 42-year-old woman was referred to our hospital for a submucosal mass on the right floor of the mouth, with a diagnosis of class 3 on aspiration cytology. Computed tomography revealed a submucosal mass with peripheral calcification on the floor of the mouth, which exhibited a hypointense rim on T2-weighted imaging and gradual nodular-like enhancement in the periphery on contrast-enhanced magnetic resonance imaging. Enucleation was performed to reach a definitive diagnosis, and CEH was confirmed pathologically. Well-defined morphology, presence of calcification, a hypointense rim on T2-weighted imaging, and weak peripheral nodular-like enhancement may be characteristic findings of CEH on the floor of the mouth. Accordingly, these imaging features may aid in differentiating CEH from low-grade malignancies and in determining the optimal management strategy.

MRI of acute neck infections: evidence summary and pictorial review

Infection of the deep neck spaces is a life-threatening acute illness that requires prompt diagnosis and treatment. Magnetic resonance imaging (MRI) offers unsurpassed soft tissue discrimination and is therefore well suited for imaging neck infections. Recently, the feasibility, diagnostic accuracy, and clinical significance of this method have been documented in patients with acute neck infections. This review article summarizes the scientific evidence, provides a practical guide to image acquisition and interpretation, reviews the most common imaging findings, and discusses some difficult diagnoses and pitfalls in acute neck infections, to help both radiologists and clinicians in managing these critically ill patients.

Imaging assessment of deep neck spaces infections: an anatomical approach

Despite the widespread use of antibiotics, deep neck infections are still a relevant clinical problem and can cause severe and potentially life-threatening complications. Imaging plays a pivotal role into the clinical management of deep neck infections, allowing identification of the source of infections, definition of the precise extension of the disease and early diagnosis of local or distant complications. The complex anatomy of deep neck spaces may hide the actual extent of disease: the knowledge of neck anatomy enables radiologists to rapidly evaluate expected routes of spread of infections and to effectively communicate crucial information to surgeons. Computed Tomography is the most used imaging modality for assessing primary site of infection, extent of disease and local complications. Magnetic resonance imaging may be used as a second level imaging modality for individuating intracranial or spinal complications. The present work aims to review the imaging of deep neck spaces infections, focusing on relevant anatomy and clinical scenarios, underlining practical teaching points for each of them. Familiarity with deep neck spaces anatomy and knowledge of most common routes of spread of infections allow the radiologist to make a prompt diagnosis and to look for early signs of potential complications.

Qualitative and Quantitative Performance of Magnetic Resonance Image Compilation (MAGiC) Method: An Exploratory Analysis for Head and Neck Imaging

The present exploratory study investigates the performance of a new, rapid, synthetic MRI method for diagnostic image quality assessment and measurement of relaxometry metric values in head and neck (HN) tumors and normal-appearing masseter muscle. The multi-dynamic multi-echo (MDME) sequence was used for data acquisition, followed by synthetic image reconstruction on a 3T MRI scanner for 14 patients (3 untreated and 11 treated). The MDME enables absolute quantification of physical tissue properties, including T1 and T2, with a shorter scan time than the current state-of-the-art methods used for relaxation measurements. The vendor termed the combined package MAGnetic resonance imaging Compilation (MAGiC). In total, 48 regions of interest (ROIs) were analyzed, drawn on normal-appearing masseter muscle and tumors in the HN region. Mean T1 and T2 values obtained from normal-appearing muscle were 880 ± 52 ms and 46 ± 3 ms, respectively. Mean T1 and T2 values obtained from tumors were 1930 ± 422 ms and 77 ± 13 ms, respectively, for the untreated group, 1745 ± 410 ms and 107 ± 61 ms, for the treated group. A total of 1552 images from both synthetic MRI and conventional clinical imaging were assessed by the radiologists to provide the rating for T1w and T2w image contrasts. The synthetically generated qualitative T2w images were acceptable and comparable to conventional diagnostic images (93% acceptability rating for both). The acceptability ratings for MAGiC-generated T1w, and conventional images were 64% and 100%, respectively. The benefit of MAGiC in HN imaging is twofold, providing relaxometry maps in a clinically feasible time and the ability to generate a different combination of contrast images in a single acquisition.

Plunging Ranula: A Case Report of a Rare Late Complication After Tongue Cancer Surgery

A plunging ranula is a benign cystic lesion in the neck formed due to mucin extravasated from a salivary gland, most commonly the sublingual gland. Ranulas have been described in association with congenital anomalies, trauma, diseases of the sublingual gland, and HIV; however, rarely, they may result as a complication of various oral and neck surgeries. Here, we report a rare case of plunging ranula that developed in an elderly male as a sequalae to surgery for tongue cancer. The patient had undergone a partial glossectomy with supra-omohyoid neck dissection for tongue carcinoma and nine months later presented with cystic swelling on the floor of the mouth that was followed by neck swelling. It was treated successfully by excision, and the histopathology confirmed the diagnosis of ranula. We postulate that the tongue cancer surgery could have caused an inadvertent injury to the ducts of the sublingual salivary gland and mylohyoid muscle, leading to the development of a plunging ranula. Our case reiterates that surgeons need to be aware of the anatomy of the submandibular and submental region to avoid any surgical trauma to the sublingual and submandibular glands and their ducts along with the associated mylohyoid muscle.

Techniques, Tricks, and Stratagems of Oral Cavity Computed Tomography and Magnetic Resonance Imaging

The oral cavity constitutes a complex anatomical area that can be affected by many developmental, inflammatory, and tumoural diseases. MultiSlice Computed Tomography (MSCT) and Magnetic Resonance Imaging (MRI) currently represent the essential and complementary imaging techniques for detecting oral cavity abnormalities. Advanced MRI with diffusion-weighted imaging (DWI) and dynamic contrast-enhanced perfusion-weighted imaging (DCE-PWI) has recently increased the ability to characterise oral lesions and distinguish disease recurrences from post therapy changes. The analysis of the oral cavity area via imaging techniques is also complicated both by mutual close appositions of different mucosal surfaces and metal artifacts from dental materials. Nevertheless, an exact identification of oral lesions is made possible thanks to dynamic manoeuvres and specific stratagems applicable on MSCT and MRI acquisitions. This study summarises the currently available imaging techniques for oral diseases, with particular attention to the role of DWI, DCE-PWI, and dynamic manoeuvres. We also propose MSCT and MRI acquisition protocols for an accurate study of the oral cavity area.

Factors Affecting Patients with Concurrent Deep Neck Infection and Acute Epiglottitis

Deep neck infection (DNI) is a serious disease of deep neck spaces that can lead to morbidities and mortality. Acute epiglottitis (AE) is a severe infection of the epiglottis, which can lead to airway obstruction. However, there have been no studies of risk factors in patients with concurrent DNI and AE. This study was performed to investigate this issue. A total of 502 subjects with DNI were enrolled in the study between June 2016 and August 2021. Among these patients, 30 had concurrent DNI and AE. The relevant clinical variables were assessed. In a univariate analysis, involvement of the parapharyngeal space (OR = 21.50, 95% CI: 2.905–158.7, p < 0.001) and involvement of the submandibular space (OR = 2.064, 95% CI: 0.961–4.434, p < 0.001) were significant risk factors for concurrent DNI and AE. In a multivariate analysis, involvement of the parapharyngeal space (OR = 23.69, 95% CI: 3.187–175.4, p = 0.002) and involvement of the submandibular space (OR = 2.465, 95% CI: 1.131–5.375, p < 0.023) were independent risk factors for patients with concurrent DNI and AE. There were no differences in pathogens, therapeutic managements (tracheostomy, intubation, surgical drainage), or hospital staying period between the 30 patients with concurrent DNI and AE and the 472 patients with DNI alone (all p > 0.05). However, we believe it is significant that DNI and AE are concurrent because both DNI and AE potentially cause airway obstruction, and concurrence of these two diseases make airway protection more difficult. The infections in critical spaces may cause the coincidence of these two diseases. Involvement of the parapharyngeal space and involvement of the submandibular space were independent risk factors associated with concurrent DNI and AE. There were no differences in pathogens between the concurrent DNI and AE group and the DNI alone group.

Sialolithiasis with abscess: An uncommon presentation of a Ludwig's angina mimic

Sialolithiasis represents the most common issue of the salivary gland, ranging from asymptomatic to airway compromising. In rapidly progressing, completely obstructive salivary stones, the presentation can mimic emergent oropharyngeal diseases, primarily Ludwig's angina. We present a case of a large and obstructive sialolith with abscess whose initial presentation was concerning for Ludwig's angina with impending airway compromise. While a common complaint, emergency providers should be aware of the nefarious presentation of an everyday complaint.

Differentiation of sublingual thyroglossal duct cyst from midline dermoid cyst with diffusion weighted imaging

PURPOSE

to differentiate sublingual thyroglossal duct cyst (TGDC) from midline dermoid cyst (DC) with diffusion weighted imaging (DWI).

MATERIALS AND METHODS

Retrospective analysis of 22 consecutive patients (11 male and 11 female aged 5-15 years) with midline cystic lesion at floor of mouth. They underwent DWI of floor of mouth. Apparent diffusion coefficient (ADC) of the cystic lesions was calculated and correlated with surgical findings.

RESULTS

The mean ADC value of TGDC of 1st observer was (2.20 ± 0.28 × 10^-3 mm²/s) and of 2nd observer was (2.28 ± 0.27 × 10^-3 mm²/s) was significantly higher than that of DC (P = 0.001) whose ADC of 1st observer was (1.55 ± 0.15 × 10^-3 mm²/s) and of 2nd observer was (1.53 ± 0.11 × 10^-3 mm²/s). There was excellent inter-observer agreement of both readings (r = 92%, P = 0.001). When ADC of 1.76 and 1.62 × 10^-3 mm²/s was used as a threshold value for differentiating TGDC from DC, the best results were obtained with area under the curve of 0.94 and 0.96, accuracy of 90% and 86%, sensitivity of 91% and 91%%, specificity of 90% and 80%, negative predictive value of 90% and 88% and positive predictive value of 92% and 84% of both reviewers respectively.

CONCLUSION

DWI is reliable and reproducible imaging modality for differentiation sublingual TGDC from DC.

Updated WHO nomenclature of head and neck lesions and associated imaging findings

This article reviews the imaging features of head and neck lesions with updated 2017 World Health Organization (WHO) nomenclature. The major WHO changes include refined terminology of existing entities, descriptions of new tumor types, elimination of defunct categories, and updated biological characterization of various tumor types. In particular, the updates pertaining to the following conditions will be reviewed: tumors of the oral cavity and oropharynx, including HPV-positive or HPV-negative squamous cell carcinoma, small cell carcinoma; tumors of the hypopharynx, larynx, trachea, and parapharyngeal space, including nomenclature revisions for laryngeal neuroendocrine tumors; tumors of the nasal cavity and paranasal sinuses including newly added entities such as NUT carcinoma and biphenotypic sinonasal sarcoma; odontogenic and maxillofacial bone tumors, including the reversal of terminology for certain cystic lesions; tumors of the salivary glands, including updated terminology related to high-grade transformation and polymorphous adenocarcinomas tumors; temporal bone lesions including modifications of the nomenclature and classification criteria; tumor-like lesions of the neck and lymph nodes, with a discussion encompassing developmental cysts, metastases of unknown primary, and heterotopia-associated neoplasia; and mucosal melanoma. Familiarity with the proper WHO terminology for conditions that might be mentioned in differential diagnoses and a general understanding of the behavior of head and neck lesions can help optimize imaging assessment and reporting.