CT of submandibular gland sialolithiasis

A comparative study of three-dimensional cone beam computed tomographic sialography and ultrasonography in the detection of non-tumoral salivary duct diseases

OBJECTIVES

To compare the overall diagnostic outcomes of 3D-CBCT sialography and ultrasonography (US) in the detection of sialolithiasis, ductal dilatation, and ductal stenosis.

METHODS

This retrospective monocentric study compared the two imaging modalities carried out in the same patients referred for salivary symptoms of the parotid and submandibular glands. The primary endpoint was the capacity of the imaging procedure to diagnose a lesion. The secondary objectives were the detection rates according to the type of lesion, analysis of the causes of failure, and the parameters of radiation exposure and safety (for 3D-CBCT sialography).

RESULTS

Of the 236 patients who received a 3D-CBCT sialography in our institution, 157 were ultimately included in the per-protocol analysis. 3D-CBCT sialography allowed detection of ductal lesions in 113 patients versus 86 with US. The two imaging modalities yielded congruent interpretations in 104 out of 157 subjects (66.2%). Higher sensitivity and negative predictive value were observed with 3D-CBCT sialography compared with US, irrespective of the lesions studied: 0.85 vs 0.65 and 0.70 vs 0.44, respectively. Regarding the sialolithiasis, both 3D-CBCT sialography and US allowed identification of lesions with high sensitivity and negative predictive value (0.80 vs 0.75 and 0.88 vs 0.78, respectively).

CONCLUSIONS

US remains the first-line examination for exploration of the salivary lesions. 3D-CBCT sialography is an alternative in case of inconclusive US, and prior to any endoscopic procedure.

Parotid Sialolithiasis in a 17-Year-Old Girl

Sialolithiasis, caused by stones in the salivary glands or their excretory ducts, is one of the most prevalent salivary gland diseases. However, it is uncommon in the pediatric population and in the parotid gland. Both conservative and surgical methods are satisfactory options for sialolithiasis treatment. Small stones (<4 mm) located distal to the intraparenchymal gland often respond to conservative treatment. If medical treatment is anticipated to fail or the stones are medium or large sized (≥4 mm), surgery is the preferred option. This report describes a rare case of intraglandular parotid stones in an adolescent patient.

Sialendoscopy and CT navigation assistance in the surgery of sialolithiasis

BACKGROUND

A sialendoscopy-assisted combined approach is well established in the surgery of sialolithiasis. In cases of proximal salivary stones, transcutaneous sialendoscopy-assisted extractions with parotid and submandibular gland preservation is the primary intention of treatment. We recently added computer tomography (CT) navigation to improve the results of this challenging surgery equally in both localizations.

PATIENTS AND METHODS

Al l the patients who submitted to sialendoscopy and sialendoscopy-assisted procedures at the tertiary institution between January 2012 and October 2020 were included in the present study. From November 2019, CT navigation was added in cases with sialolithiasis and a presumably poor sialendoscopic visibility. We evaluated the parameters of the disease, diagnostic procedures, sialendoscopic findings and outcomes, with or without optical surgical navigation.

RESULTS

We performed 178 successful salivary stone removals in 372 patients, of which 118 were combined sialendos-copy-assisted approaches, including 16 transcutaneous proximal, 10 submandibular and 6 parotid stone operations. Surgical navigation was used in six patients, four times for submandibular and twice for parotid sialolithiasis. These were all non-palpable, sialendoscopically invisible or partially visible stones, and we managed to preserve five of the six salivary glands.

CONCLUSIONS

The addition of CT navigation to sialendoscopy-assisted procedures for non-palpable, sialendoscopically invisible and fixed stones is a significant advantage in managing sialolithiasis. By consistently performing sialendoscopy and related preservation procedures, we significantly reduced the need for sialoadenectomies in patients with obstructive salivary gland disease.

Three-dimensional cone-beam CT sialography in non tumour salivary pathologies: procedure and results

OBJECTIVES

Non-tumour salivary diseases are common. Imaging studies are essential for their diagnosis and before undergoing an endoscopic or surgical treatment. In this study, we aimed at presenting our procedure and results obtained with three-dimensional CBCT (3D-CBCT) sialography for non-tumour salivary gland diseases.

METHODS

Patients with parotid or submandibular salivary symptoms were examined by 3D-CBCT sialography. They received an intraductal injection of 0.5 mL of water-soluble contrast medium maintained in the gland, followed by examination in a NewTom wide-field CBCT device. Images were processed with multiplanar and 3D reconstructions.

RESULTS

A ductal exploration could be performed until the fourth divisions. The main lesions found were stones, stenosis, dilatations and "dead tree" appearance of the ductal system. No side effects of the catheterization or the iodine contrast were reported, nor tissue damages related to the contrast keeping technique.

CONCLUSIONS

3D-CBCT sialography seems to represent a reliable non-invasive diagnostic tool for ductal salivary diseases. More studies are needed to assess the value of 3D-CBCT sialography compared with conventional imaging.

Parotid sialolithiasis in a two-year-old boy

Sialolithiasis is caused by the obstruction of a salivary gland or its excretory duct by the formation of calcareous concretions or sialoliths; this results in salivary ectasia and provokes subsequent dilation of the salivary gland. Sialolithiasis is relatively common, accounting for 30% of salivary diseases; however, it is rarely observed in childhood. This case report describes a 2-year-old male patient who complained of a painful swelling over the right cheek, and presented with palpable stones and pus discharge from the orifice of the right Stensen's duct. Computerized tomography of the neck confirmed the diagnosis, and the patient received intravenous empiric antibiotics combined with intraoral sialolithotomy. We also provide a review of the spectrum of concepts regarding the pathogenesis, diagnosis, and treatment of sialolithiasis.

Assessment of the role of cone beam computed sialography in diagnosing salivary gland lesions

Purpose

The purpose of this study was to assess cone-beam computed (CBCT) sialography imaging in the detection of different changes associated with lesions of salivary glands.

Materials and Methods

This study consisted of 8 cases with signs and symptoms from salivary gland lesions. Conventional sialography using digital panoramic and lateral oblique radiographs and CBCT sialography were performed for each subject. The radiographs were evaluated by 3 radiologists independently of each other. The results were compared between conventional sialography and CBCT sialography in the evaluation of various lesions associated with the salivary glands.

Results

There was an agreement between the radiologists in interpreting the lesions that affected salivary glands with both techniques. The detection of the presence of stones or filling defects, stenosis, ductal evagination, dilatation, and space occupying lesions was 83% for conventional sialography compared with CBCT sialography. CBCT sialography was superior to conventional sialography in revealing stones, stenosis, and strictures, especially in the second and third order branches.

Conclusion

It would be advisable to perform CBCT sialography in cases of obstructive salivary gland diseases for better demonstration of the ductal system of the gland.

Magnetic resonance imaging sialolithography: direct visualization of calculi in the submandibular gland using susceptibility-weighted imaging (SWI) at 3 Tesla

Magnetic resonance imaging (MRI) sialolithography is a useful technique for evaluating acute and chronic sialadenitis. However, its major weakness is that stones are not imaged directly. We have developed an MRI technique that allows specific identification and localization of calculi within the submandibular salivary gland or duct. This test is noninvasive and does not require ionizing radiation or a sialogogue. By using 3-dimensional susceptibility-weighted imaging, one can probe MRI signal phase changes. Corrected positive filtered phase and magnitude images, acquired using susceptibility-weighted imaging, allowed identification and anatomical localization of calcified calculi in the submandibular gland with efficacy comparable to computed tomography.

Cone beam computed sialography of sialoliths

Cone beam CT is an emerging imaging modality used in maxillofacial imaging. This paper describes the use of cone beam sialography in two patients with salivary gland obstruction. In both cases, the obstruction was identified. The dose is comparable with conventional fluoroscopic techniques and has the advantage that the data may be viewed in a series of fine slices and in three dimensions, which may help in diagnosis and further management of the patient.

MR sialography: the effect of a sialogogue and ductal occlusion in volunteers

MR sialography using heavily T(2) weighted projection techniques relies upon saliva for image contrast, and the visualization of normal ducts is often limited. Methods used to increase the volume of intraductal saliva during imaging in order to improve duct visualization have not been previously evaluated. The effect of a sialogogue and passive ductal occlusion on the ability to visualize the main and intraglandular salivary gland ducts during MR sialography was investigated. Three-dimensional (3D) T(2) weighted MR sialograms were obtained from 12 healthy volunteers with and without the combined use of a sialogogue and passive ductal occlusion pad adjacent to the parotid duct orifice on one side. Two radiologists (in consensus) subjectively evaluated ductal visualization and image artefacts on the resulting blinded maximum intensity projections. The results demonstrate that main duct visualization was significantly improved (p<0.00001) by this technique, with no significant change seen in image artefacts. Although an improvement in intraglandular duct visualization was noted, this was not statistically significant (p = 0.05). Thus, the use of a sialogogue and passive ductal occlusion improves visualization of the main parotid duct in volunteers undergoing MR sialography. Further optimization and evaluation of this approach should lead to improvements in the MR sialography examination of patients.

Giant Sialolith of the Submandibular Salivary Gland

We report the case of a 48-year-old man who had an unusually large submandibular gland sialolith (2.6 cm in greatest dimension), which led to sialadenitis and subsequent abscess formation. We describe the management of this patient and review the literature with emphasis on the various modalities available for diagnostic imaging.

Speichelgangsendoskopie in der Diagnostik und Therapie von obstruktiven Speicheldrüsenerkrankungen

BACKGROUND

In 5-10% of all cases with an obstructive disease of the major salivary glands, a diagnosis cannot be established by conventional radiological imaging or ultrasound. Using sialendoscopes, intraductal pathology can made visible to the surgeon, aiding in diagnosis and adequate treatment.

MATERIAL AND METHODS

Between 2001 and 2005, 369 sialoscopies were performed on 318 patients in the ENT department of the University of Erlangen-Nuremberg. Semi-rigid sialoscopes with an external diameter of between 0.7 and 1.7 mm were used.

RESULTS

In 34.9% of cases conservative treatment was necessary. In 65.1%, based on the sialoscopic findings, further therapeutic procedures such as extracorporeal shock wave lithotripsy, interventional sialoscopy or duct slitting were required and planned. Of 133 performed interventional sialoscopies, 83.5% were successful.

CONCLUSIONS

Sialoscopy is a useful diagnostic and therapeutic tool in obstructive salivary gland disease. Interventional sialoscopy has been performed with high success rates and has proven to be an important part in our concept of a gland preserving therapeutic regime.

Imaging Studies for Head and Neck Infections

Imaging the head and neck presents a unique challenge because of the dense concentration of complex anatomy and the importance of lesion localization in formulating the differential diagnosis and prognosis. Critical imaging features such as the ability to define fascial borders of soft tissue neck compartments, the demonstration of intricate anatomy such as the temporal bones and paranasal sinuses, and the noninvasive assessment of vascular integrity have improved greatly in recent years in parallel with the rapid technologic advances in multidetector CT and MRI. After comparing the available imaging techniques, this article explores the imaging findings by anatomic region.

Inflammatory conditions of the salivary glands

Inflammatory conditions are the most common pathology to affect the salivary glands, of which sialolithiasis is the most frequent etiology. This article reviews the role of all imaging modalities in the management of inflammatory salivary disease. The technique for performing salivary gland ultrasound is described with some common pitfalls. The typical features of a comprehensive range of pathology including obstructive and infective sialadenitis, Sjogren's syndrome, sarcoidosis, HIV sialopathy, and their complications are described.

Parotid Duct Sialolithiasis in a Dog

Computed tomography was used to evaluate a 7-year-old English bulldog with a history of facial swelling and to aid in the diagnosis of parotid duct sialolithiasis. Removal of the sialolith with repair of the duct was not possible because of ductal fibrosis. Histological evaluation revealed glandular atrophy and fibrosis with lymphoplasmacytic inflammation. The parotid duct was ulcerated and fibrotic, with a mixed inflammatory infiltrate. Surgical excision of the parotid duct and salivary gland was curative.

US of the major salivary glands: anatomy and spatial relationships, pathologic conditions, and pitfalls

Ultrasonography (US) is useful for differential diagnosis of diseases of the salivary glands. In acute inflammation, salivary glands are enlarged and hypoechoic with increased blood flow; they may contain multiple small, oval, hypoechoic areas. In chronic inflammation, salivary glands are normal sized or smaller, hypoechoic, and inhomogeneous. Sialolithiasis appears as markedly hyperechoic lines or points with distal acoustic shadowing. Sialosis appears as enlarged hyperechoic glands without focal lesions or increased blood flow. The US features of advanced Sjögren syndrome include inhomogeneous salivary glands with scattered small, oval, hypoechoic or anechoic areas, usually well defined, and increased parenchymal blood flow. Pleomorphic adenomas are usually hypoechoic, well-defined, lobulated lesions with posterior acoustic enhancement that may contain calcifications; Warthin tumors are usually oval, hypoechoic, well-defined lesions that often contain anechoic areas and are often hypervascularized. Malignant neoplasms of the salivary glands may have irregular shapes, irregular borders, blurred margins, and a hypoechoic inhomogeneous structure or may have a benign appearance. Salivary gland cysts have well-defined margins, anechoic contents, posterior acoustic enhancement, and no internal blood flow. However, US appearances of some diseases may overlap, thus producing diagnostic pitfalls.

[Imaging of salivary lithiasis]

Lithiasis is the most common disease of salivary glands after mumps. The purpose of this review is to analyze the respective role of the different available imaging techniques for the diagnosis of lithiasis and related complications since the treatment of salivary lithiasis has evolved with the emergence of minimally invasive and non surgical techniques. In spite of its limitations, US represents an excellent first line imaging technique because it is non-invasive and widely available. Non contrast helical CT with multiplanar reconstructions seems to be the gold standard for the diagnosis of lithiasis, especially when small and poorly calcified since these may not be visible on standard radiographs. CT allows accurate characterization of the number and position of lithiasis. MR Sialography is increasingly replacing the more invasive conventional sialography for the non invasive visualization of the ductal system of major salivary glands even though conventional sialography has a higher spatial resolution.

MR imaging of salivary glands

Diagnostic imaging of salivary glands has been revolutionized with the advent of cross-sectional imaging modalities like CT and MR imaging. In the era before CT, imaging of the salivary glands was relatively unrewarding and was used uncommonly by ear-nose-throat surgeons. Early diagnostic tests like plain films and sialography evaluated dilated parotid ducts and calculus disease within ducts or glands. Full evaluation of salivary glands, especially deep lobes of parotid gland and masses of minor salivary glands, was not possible by these methods, however. Imaging of the parotid glands has developed significantly since that time. CT and MR imaging greatly compliment physical and endoscopic examinations (and previous favorites like sialography) by direct visualization of previously blind areas of the salivary glands and extension of the disease process in surrounding tissue planes.

A Case of Giant Sialolith of the Submandibular Salivary Gland

Sialolithiasis is the most common disease of the salivary glands. This report describes the case of a patient who had an unusually large submandibular gland sialolith that was completely encased in the glandular substance. The author describes the management of this patient and reviews the literature.

MR imaging of salivary glands

In conclusion, if a parotid gland mass is bilateral, it is more likely to be Warthin's tumor, especially if it does not enhance. Less likely, it could be lymphoepithelial cyst or necrotic lymph node. A unilateral, non-enhancing mass with a high T2 signal is more likely to be a Warthin's tumor and less likely a necrotic lymph node or first branchial cleft cyst. If the mass is unilateral, shows postcontrast enhancement, has a high T2 signal, and does not invade surrounding tissue planes, it is more likely to be a pleomorphic adenoma. An intermediate to low T2 signal mass-with or without invasion of surrounding tissue planes--is more likely to be a malignant mass such as adenocystic or mucoepidermoid carcinoma. Biopsy is superior and the gold standard for diagnosis and cannot be replaced by MR imaging, however.

Major salivary gland imaging

The algorithm for imaging the salivary glands depends on the clinical scenario with which the patient presents to the clinician. Because of the importance of identifying small calculi in the gland or salivary duct as the cause of the symptom complex, nonenhanced computed tomography is often the best initial study for the evaluation of the painful gland. If an infiltrative neoplasm is highly suspected, nonenhanced and enhanced magnetic resonance (MR) imaging may be superior in demonstrating perineural, meningeal, and skull base invasion. Sialography is reserved for the evaluation of chronic sialadenitides unrelated to sialolithiasis. Thin-section MR techniques for MR sialography may soon replace conventional sialography.

Prospective comparison of magnetic resonance sialography and digital subtraction sialography

We sought to compare the diagnostic utility of magnetic resonance sialography (MRS) and digital subtraction sialography (DSS) in patients with suspected sialolithiasis or sialadenitis. Sixteen consecutive patients (4 female and 12 male, mean age 51+/-16 years) with suspected sialolithiasis or sialadenitis underwent DSS by a standard technique and MRS. MRS was obtained with a T2-weighted single-shot TSE sequence (TR/TE 2800/1100 msec, acquisition time 7 seconds) using a quadrature head (n = 16) and a surface coil (n = 8). Nineteen symptomatic glands were investigated with DSS: eight submandibular glands in 6 patients (two bilateral) and unilateral parotid glands in 11 patients. MRS was always carried out to visualize gland ducts bilaterally. The ductal system was visualized in all glands examined by MRS. DSS depicted the ductal system in all 11 parotid glands, but only 4 of the 8 submandibular glands (50%). Sialolithiasis was diagnosed in three cases (one parotid, two submandibular glands) by MRS and in two cases by DSS. DSS demonstrated tertiary branching ducts and MRS secondary branching ducts. MRS is able to visualize the ductal system of the parotid and submandibular gland noninvasively and is thus not dependent on successful cannulation of the orifice of the ductal system. Our preliminary data indicate that MRS is useful for diagnosing sialolithiasis. MRS allows diagnosis of sialadenitic changes, but DSS achieves a better diagnostic performance due to higher spatial resolution.

Sialolithiasis

Sialolithiasis is one of the most common problems that afflict the salivary glands and is a major cause of salivary gland dysfunction. Sialolithiasis is frequently encountered in clinical practice. The mechanism for stone formation is incompletely understood. The clinical diagnosis and standard management of sialolithiasis are discussed, and new modalities for treatment are also presented in this article.