Evaluation of submandibular and parotid salivary glands by ultrasonography in patients with diabetes

BACKGROUND

Microvascular complications of diabetes mellitus (DM) include oral manifestations and complications, including xerostomia, reduced salivary flow, susceptibility to infection, periodontal disease and salivary gland enlargement.

OBJECTIVE

The present study aims to evaluate B-mode ultrasonography (USG) parameters such as size, volume and echogenicity of the submandibular and parotid salivary glands on both sides, shear-wave elastography (SWE) value and colour Doppler properties in patients with DM and healthy control groups.

METHODS

In total, 160 right and left submandibular glands and 160 right and left parotid glands of 80 patients, 40 patients (20 type 1 DM, 20 type 2 DM) and 40 healthy control group, between the ages of 18-70 were examined by USG. Echogenicity, parenchyma internal structure, margin and dimensional measurements (antero-posterior length, supero-inferior length, medio-lateral length and volume) and colour Doppler with 'ML 6-15-D Matrix Array (4-15 MHz)' probe, shear-wave elastography '9L-D (2-8 MHz)' probe was investigated.

RESULT

Statistically significant difference was observed in echogenicity in the right submandibular gland, echogenicity in the right parotid gland, margin characteristics, parenchymal homogeneity and colour Doppler characteristics between the type 1 DM, type 2 DM and control groups (p < .05). It was observed that the size, volume and SWE values of both submandibular and parotid glands were higher in the DM patient group than in the control group. Higher values were observed in type 2 DM compared to type 1 DM in the patient group.

CONCLUSION

USG is an effective imaging technique in investigating the effects of diabetes on the submandibular and parotid salivary glands.

Evaluation of major salivary glands with ultrasonography in multiple sclerosis patients

BACKGROUND

This study aimed to investigate the homogeneity of the major salivary glands in multiple sclerosis (MS) patients using ultrasonography (USG), assess DMFT indices, measure resting salivary flow rates, and compare these values with healthy individuals.

METHODS

In this study, 20 individuals diagnosed with Relapsing-Remitting Multiple Sclerosis (RRMS) (mean age 36.15 ± 8.51) and 20 systemically healthy individuals (mean age 35.7 ± 9.22) were included. Oral and radiologic examinations were performed in all individuals. The parotid and submandibular salivary glands were examined using USG, and their homogeneity was assessed based on the scoring system recommended by the Outcome Measures in Rheumatology Clinical Trials (OMERACT) study group. Resting salivary flow rates and DMFT indices were measured, and the obtained data were subjected to statistical analysis.

RESULTS

The parotid glands exhibited more heterogeneity on USG within the MS patient group than the control group, with a statistically significant difference between the two groups (p = 0.015). A statistically significant correlation was observed in total homogeneity values between the patient and control groups (p = 0.021). Furthermore, the MS patient group exhibited higher DMFT indices and lower salivary flow rates than the control group. The difference between the DMFT indices and salivary flow rate between the patient groups was statistically significant (p = 0.004 and p = 0.002 respectively).

CONCLUSIONS

The parenchyma of the major salivary glands in MS patients exhibited decreased homogeneity than the healthy controls. Additionally, the MS group showed a decrease in salivary flow rate and an increase in the DMFT index. Autonomic dysfunction and medications used for MS are thought to cause salivary gland hypofunction and dry mouth. It can be interpreted that hyposalivation and motor skill losses in MS patients lead to an increase in DMFT index.

Proposal for standardized ultrasound analysis of the salivary glands: Part 1 submandibular gland

Objectives

The Salivary Gland Committee of the American Academy of Otolaryngology-Head and Neck Surgery seeks to standardize terminology and technique for ultrasonograpy used in the evaluation and treatment of salivary gland disorders.

Methods

Development of expert opinion obtained through interaction with international practitioners representing multiple specialties. This committee work includes a comprehensive literature review with presentation of case examples to propose a standardized protocol for the language used in ultrasound salivary gland assessment.

Results

A multiple segment proposal is initiated with this focus on the submandibular gland. We provide a concise rationale for recommended descriptive language highlighted by a more extensive supplement that includes an extensive literature review with additional case examples.

Conclusion

Recommendations are provided to improve consistency both in performing and reporting submandibular gland ultrasound.

Value of High-Frequency Ultrasonography in the Qualitative and Semi-Quantitative Assessment of Immunoglobulin G4-Related Submandibular Sialadenitis

OBJECTIVE

To assess the value of high-frequency ultrasonography in the evaluation of immunoglobulin G4-related submandibular sialadenitis (IgG4-SS).

METHODS

Thirty-four submandibular glands in 17 patients with IgG4-SS were retrospectively enrolled, as well as 34 submandibular glands in 17 healthy control subjects. Qualitative ultrasonic features including submandibular gland size, border, echogenicity, and vascularity were reviewed. Two different scoring systems (0-16 and 0-48, respectively) were used for semi-quantitative analysis of imaging features. Comparison of both qualitative and semi-quantitative ultrasonic analysis were made between patients with IgG4-SS and healthy controls. Spearman correlation was used to explore relationships between variables.

RESULTS

The submandibular glands with IgG4-SS presented with enlarged size, rough border, increased vascularity, and abnormal echogenicity (All P < .05). The most common echogenicity pattern for IgG-SS was diffuse hypoechoic foci pattern (44.1%), followed by superficial hypoechoic pattern (20.6%), tumor-like pattern (14.7%), and diffuse hypoechogenicity pattern (11.8%). Most IgG4-SS glands presented linear hyperechogenicity in parenchyma (91.2%). Based on both scoring system, scores of IgG4-SS were significantly higher than those of the controls (All P < .05). Association analysis of both scoring systems showed positive correlation of scores with vascularity in the gland parenchyma (All P < .05).

CONCLUSION

The ultrasonic features of IgG4-SS comprise enlarged gland, rough border, increased vascularity, and abnormal echogenicity, which correlate with its pathological characteristics. The most common echogenicity pattern for IgG4-SS was diffuse hypoechoic foci pattern. Semi-quantitative analysis systems could be useful in the assessment of IgG4-SS. Ultrasound is a potential, valuable, and non-invasive tool for the diagnosis and evaluation of IgG4-SS.

Salivary ultrasonography and histopathologic evaluation of secondary Sjögren's syndrome in rheumatoid arthritis patients

Novel modalities, such as salivary ultrasonography (SGUS) and shear wave elastography (SWE), have previously been introduced to evaluate Sjögren's syndrome (SS). However, in secondary SS (sSS), the diagnostic performance of SGUS and its relationship with clinicopathological characteristics have not yet been clearly defined. In this study, we aimed to investigate sSS in RA patients using SGUS and SWE and sought to determine its pathological correlations. Thirty-one RA patients who presented with sicca symptoms were included to be evaluated on SS, and were compared with 18 primary SS (pSS) patients. All subjects were assessed through SGUS, SWE, and conventional diagnostic approaches for SS, including minor salivary gland biopsy (MSGB). In SGUS evaluation, two separate scoring systems, suggested by Hocevar and OMERACT, were used. Among 31 RA patients with sicca symptoms, 19 (61.2%) were diagnosed as sSS. Similar to pSS, SGUS showed good diagnostic performance (sensitivity 68.4% and 78.9%, and specificity 91.7% and 75.0% for Hocever and OMERACT, respectively) in differentiating sSS from RA patients with simple sicca symptoms. The sSS and pSS patients exhibited significantly higher lymphoid infiltration areas in MSGB than RA patients without SS. Focus score and lymphoid infiltration areas correlated well with sonographic severity. Severity of fibrosis in MSGB showed better positive correlation with SWE than with SGUS. Similar to pSS, SGUS shows good diagnostic performance for sSS in RA patients. SWE reflects histopathologic chronicity of MSGB well in both pSS and sSS.

Shear wave elastography as a potential additional diagnostic tool in primary Sjögren's syndrome: an observational study

The primary aim of this study was to verify if shear wave elastography can be used to evaluate salivary gland involvement in primary Sjögren's syndrome (pSS). The secondary objective was to establish an accurate cut-off value for parotid and submandibular salivary gland stiffness and to verify whether there are any distinctions among pSS patients with or without subjective mouth dryness. This prospective study included 45 patients with pSS (2016 ACR/EULAR classification criteria) and 108 healthy controls. All subjects underwent bilateral shear wave elastography of the parotid and submandibular salivary glands. Clinical data of pSS patients were collected and compared to elastography results. Patients with pSS had significantly higher shear wave elastography values for the parotid and submandibular salivary glands than the controls. There were no statistical differences in SWE values between patients with or without mouth dryness. The optimal cut-off value (mean value of 4 salivary glands shear wave elastography results) to distinguish patients with or without pSS was 13.19 kPa with sensitivity = 97.8% and specificity = 100.0%. It was, therefore, confirmed that shear wave elastography measurement of salivary glands has strong predictive ability in pSS detection (AUC 97.8%, 95% CI 93.4-100.0%). Shear wave elastography seems to be a promising, non-invasive and simple quantitative adjunct test to support the diagnosis of pSS with good sensitivity and specificity. More extensive prospective studies are needed to standardize a study protocol.

Salivary gland ultrasonography in primary Sjögren's syndrome from diagnosis to clinical stratification: a multicentre study

Background

To determine the diagnostic accuracy of major salivary gland ultrasonography (SGUS) in primary Sjögren’s syndrome (pSS) using the novel Outcome Measures in Rheumatology Clinical Trials (OMERACT) scoring system in a large-scale multicentre study.

Methods

SGUS was conducted for 246 pSS patients, 140 control subjects with conditions other than SS and 27 healthy control subjects. The echostructure features from the parotid and submandibular glands on both sides were graded using the novel OMERACT scoring system. Receiver operating characteristic curves were used to describe the diagnostic accuracy of the scoring system for pSS. The associations between the SGUS and disease characteristics were analysed to evaluate the clinical value of SGUS for pSS.

Results

The US scores in the pSS group were significantly higher than those in the non-pSS group (p < 0.001). The level of diagnostic accuracy was comparable with the scores of all four glands (AUC=0.908) when only the parotid and submandibular glands on either side were scored (AUC=0.910, 0.904, respectively). The optimal cut-off value for the left (right) parotid gland and the left (right) submandibular gland was 4, with maximal sensitivity (75.6% and 77.2%, respectively) and specificity (91.6% and 92.2%, respectively). The pSS patients with positive SGUS results presented a longer disease duration, parotid enlargement, dental loss and higher levels of serological markers, such as anti-SSA, anti-SSB, positive RF, IgG and γ-globulin%.

Conclusions

SGUS with the OMERACT scoring system yields high sensitivity and specificity, demonstrating high diagnostic feasibility for pSS. The SGUS may have implications for deciding disease severity and treatment efficacy.

Salivary gland ultrasonography in patients with connective tissue diseases: a multi-center observational study

OBJECTIVE

Ultrasonography (US) of salivary glands (SGUS) is a non-invasive tool that allows for diagnosing primary Sjögren's syndrome (pSS) or secondary SS (sSS). However, little is known about the prevalence of US findings of SS in other connective tissue diseases (CTDs). The aim of this multicentre observational study was to evaluate, in CTD patients with or without SS, the prevalence of abnormal SGUS findings and the possible association of the findings with clinical or biological phenotypes.

METHODS

B-Mode SGUS was performed by one operator blinded to clinical data. Each SG was semi-quantitatively rated on a scale from 0-4 according to the Jousse-Joulin score; a score ≥ 2 was considered pathological.

RESULTS

Data for 194 patients were analyzed (pSS, n = 30; sSS, n = 39; other CTDs, n = 77; controls, n = 48). SGUS findings were abnormal in 80%, 67%, 25% and 2% of patients, respectively. Independent of the underlying disease, age and sex, abnormal SGUS findings were significantly associated with presence of anti-SSA antibodies (p< 0.001), pSS (p< 0.001) and sSS (p< 0.01). Among SS patients, abnormal SGUS findings were associated with the presence of hypergammaglobulinemia, anti-SSA antibodies, objective eye dryness and increased anti-nuclear antibody level, with no difference in EULAR Sjögren's Syndrome Disease Activity Index.

CONCLUSION

Abnormal SGUS findings were associated with anti-SSA antibody positivity independent of the underlying disease. In SS patients, abnormal findings were associated with immunologic features and mouth involvement. Among CTD patients, SGUS changes may be associated with a particular immune profile.

Ultrasonographic characteristics of major salivary glands in anti-centromere antibody-positive primary Sjögren's syndrome

Purpose

To investigate salivary gland ultrasonography (SGUS) findings in primary Sjögren’s syndrome (pSS) patients positive for the anti-centromere antibody (ACA) and compare these with those in ACA-negative pSS patients.

Methods

We analyzed demographic, clinical, laboratory, and SGUS data of pSS patients who fulfilled the 2002 American-European Consensus Group classification criteria for pSS. SGUS findings of four major salivary glands (bilateral parotid and submandibular glands) were scored in five categories and compared between ACA-positive and ACA-negative pSS patients. Linear regression analysis was performed to elucidate the factors associated with SGUS score.

Results

In total, 121 pSS patients were enrolled (19, ACA-positive). The ACA-positive patients were older (67.0 vs 58.0 years, P = 0.028), whereas anti-Ro/SSA and anti-La/SSB positivity was more prevalent in the ACA-negative group (89.2% vs 21.1%, P < 0.001, and 47.1% vs 10.5%, P = 0.007, respectively). The total SGUS and hypoechoic area scores were lower in ACA-positive patients (16.0 vs 23.0, P = 0.027, and 4.0 vs 7.0, P = 0.004, respectively). In univariate regression analysis, being positive for unstimulated salivary flow rate (USFR < 1.5 ml/15 min), anti-Ro/SSA, and rheumatoid factor were positively associated whereas ACA positivity was negatively associated with the SGUS score. In multivariate regression analysis, being positive for USFR, anti-Ro/SSA, and rheumatoid factor showed significant association with the SGUS score.

Conclusions

ACA-positive pSS patients showed a lower SGUS score than ACA-negative patients, which was especially prominent in the hypoechoic area component.

Sonographic findings of immunoglobulin G4-related sialadenitis and differences from Sjögren's syndrome

OBJECTIVE

To evaluate ultrasonic features of the major salivary glands in patients with immunoglobulin G₄-related sialadenitis (IgG₄-RS) and to explore the differences between IgG₄-RS and Sjögren's syndrome (SS).

METHOD

We conducted the study in 150 patients with IgG₄-RS and 100 patients with SS. Ultrasonographic variables of the static images of major salivary glands were analysed. An experienced radiologist scored the confidence rating regarding the presence of the characteristic imaging findings using a five-grade rating system. Ultrasonography scores between IgG₄-RS and SS were compared.

RESULTS

The major salivary glands were significantly larger in patients with IgG₄-RS than in the SS group. The main features of ultrasonography of the salivary glands in IgG₄-RS were various hypoechoic lesions and increased colour Doppler signalling. In contrast, the major salivary glands in SS exhibited hyperechoic lines and/or spots and obscuration of the gland configuration. The scores of the summarized sonographic characteristics also showed statistically significant differences between the IgG₄-RS and SS groups.

CONCLUSION

This study revealed different ultrasonic features of the major salivary glands in patients with IgG₄-RS and SS. The scored sonographic features were helpful in differentiating IgG₄-RS from SS. Consequently, we suggest that ultrasonography of major salivary glands could be a useful imaging procedure in the evaluation of patients suspected of having IgG₄-RS.

Patient-based reliability of the Outcome Measures in Rheumatology (OMERACT) ultrasound scoring system for salivary gland assessment in patients with Sjögren's syndrome

BACKGROUND

To assess the reliability of the consensually agreed US definitions of major salivary gland lesions and the US scoring system for salivary gland assessment in patients with SS.

METHODS

Nine experienced sonographers scanned and read the US images of both parotid glands (PGs) and submandibular glands (SMGs) in eight patients with primary and secondary SS in two rounds. A consensually agreed four-grade semi-quantitative scoring was applied in B-mode for morphological lesions: grade 0, normal; grade 1, mild inhomogeneity without anechoic or hypoechoic areas; grade 2, moderate inhomogeneity with focal anechoic or hypoechoic areas; grade 3, severe inhomogeneity with diffuse an- or hypoechoic areas occupying the entire gland or fibrous gland. The presence or absence of typical SS lesions, i.e. the Sjögren's signature, was scored binary. Intra- and interreader reliabilities were computed using weighted and unweighted Cohen's and Light's κ coefficients.

RESULTS

The mean prevalence of grades 0-3 in PG were 43, 17, 23 and 31% and 28, 14, 33 and 32% for the SMGs, respectively. The weighted κ for intrareader reliability ranged from 0.44 to 1 for grading and 0.64 to 1 for the Sjögren's signature of PG and 0.59 to 1 and -0.09 to 0.6 for SMGs, respectively. The interreader reliability κ for grading in PG was 0.62 (95% CI 0.47, 0.74) and for Sjögren's signature it was 0.36 (95% CI 0, 0.43); in SMG it was 0.62 (95% CI 0.47, 0.72) and 0.03 (95% CI 0, 0.07) respectively.

CONCLUSIONS

The consensually agreed novel US scoring system for major salivary gland lesions showed substantial intra- and interreader reliability in patients with SS. The reliability of the Sjögren's signature was moderate.

Salivary glands ultrasonography as a diagnostic aid in Sjögren syndrome: A prospective pilot investigation

OBJECTIVE

The aims of this pilot investigation were to calculate the levels of sensitivity and specificity of salivary glands ultrasonography (SGUS) in diagnosing Sjögren syndrome (SS) and to assess the ultrasonographic findings of parotid and submandibular glands.

STUDY DESIGN

Patients diagnosed with SS or dry mouth and healthy controls were enrolled. Bilateral parotid and submandibular glands were assessed for (1) parenchymal inhomogeneity (PIH), (2) median size of the glands, (3) visibility of glandular posterior borders, and (4) size of sialolith, if present.

RESULTS

This study included 34 female patients, of whom 12 had SS (35.3%), 12 had dry mouth (35.3%), and 10 were healthy controls (29.4%). Patients with SS showed higher PIH scores in all glands with the median differences being statistically higher in the right and left parotids and left submandibular glands (P < .001, P = .012, and P < .001, respectively). SGUS, with a PIH cutoff ≥2, showed a sensitivity of 100% and a specificity of 81.6% for detecting SS. The majority of SS had invisible glandular posterior borders (P < .001). Median size of the glands and size of the sialolith did not show any statistically significant differences between groups.

CONCLUSIONS

SGUS is a noninvasive imaging modality with good sensitivity and specificity that might be valuable as a diagnostic aid for SS.

Ultrasonography predicts the results of labial salivary gland biopsy in patients with suspected Sjögren's syndrome: a matrix risk model

Objective:

Although a positive result of labial salivary gland biopsy (LSGB) is critical for the diagnosis of Sjögren’s syndrome, rheumatologists prefer assessing the non-invasive objective items and hope to learn the predicted probability of positive LSGB before referring patients with suspected Sjögren’s syndrome to receive biopsy. This study aimed to explore the predictive value of combined B-mode ultrasonography (US) and shear-wave elastography (SWE) examination on LSGB results.

Methods:

A derivation cohort and later a validation cohort of patients with suspected Sjögren’s syndrome were recruited. All participants received clinical assessments, B-mode US and SWE examination on bilateral parotid and submandibular glands before LSGB. Positive LSGB was defined by a focus score ⩾1 per 4 mm² of glandular tissue.

Results:

In the derivation cohort of 91 participants, either the total US scores or the total SWE values of four glands significantly distinguished patients with positive LSGB from those with negative results (area under the curve (AUC) = 0.956, 0.825, both p < 0.001). The positive predictive value (PPV) was 100% in patients with total US scores ⩾9 or with total SWE values ⩾33 kPa. The negative predictive value (NPV) was 100% in patients with total US scores <5, but 68% in patients with total SWE values <27 kPa. A matrix risk model was derived based on the combination of total US scores and total SWE values. Patients can be stratified into high, moderate, and low risk of positive LSGB. In the validation cohort of 52 participants, the PPV was 94% in the high-risk subpopulation and the NPV was 93% in the low-risk subpopulation.

Conclusion:

A novel matrix risk model based on the combined B-mode US and SWE examination can help rheumatologists to make a shared decision with suspected Sjögren’s syndrome patients on whether the invasive procedure of LSGB should be performed.

Diagnostic accuracy of salivary gland ultrasound in Sjögren's syndrome: A systematic review and meta-analysis

BACKGROUND

To systematically review the diagnostic accuracy of salivary gland ultrasound in primary Sjögren's syndrome (pSS).

METHODS

PubMed, Embase, CINAHL, Cochrane Central and Scopus and ClinicalTrials.gov were searched to identify diagnostic or validation studies in patients with pSS meeting the diagnostic criteria. A diagnostic test meta-analysis was performed using a bivariate model to calculate the pooled sensitivity, specificity, positive/negative likelihood ratios, and the diagnostic odds ratio. Meta-regression analyses were done for several pSS covariates.

RESULTS

Sixty-five studies met our criteria for the qualitative review. Fifty-four studies with a total of 6087 patients were included in the meta-analysis. Pooled sensitivity for salivary gland ultrasound was 80% [95% confidence interval (CI): 77-83%; I 2 = 78%], and specificity was 90% (95% CI: 87-92%; I 2 = 76%). The pooled positive and negative likelihood ratios were 8 (95% CI: 6.4-10) and 0.22 (95% CI: 0.19-0.25), respectively. The corresponding pooled diagnostic odds ratio (DOR) was 37 (95% CI: 28-48). Separate meta-regression models resulted in similar diagnostic estimates: (a) adjusted for mean age: sensitivity 81% (95% CI:77-84%; I 2 = 99%) and specificity 90% (95% CI: 87-93%; I2 = 99%); (b) adjusted for mean disease duration, sensitivity 79% (95% CI:72-84%; I 2 = 99%), and specificity 90% (89-94%; I 2 = 99%). The diagnostic estimates were robust to sensitivity analyses by quality criteria, pSS diagnostic criteria and ultrasound scoring systems.

CONCLUSION

Salivary gland ultrasound is a valuable modality for the diagnosis of Sjögren's syndrome. It is plausible that salivary gland ultrasound can be used as an important criterion for the diagnosis of pSS.

Current status of imaging of Sjogren's syndrome

Primary Sjögren's syndrome (pSS) is an autoimmune disease, which involves salivary glands (SG) and extra glandular organs. Today, Sjögren's patients' diagnosis is based on classification criteria taking into account five objective tests, including histology, immunology, two ophthalmological tests, and salivary flow evaluation. To date, the challenge is to find the right imaging tool for diagnosis, follow up, and prognosis of pSS. The objective of this review is to describe as to what are these imaging modalities and particularly the place and validity of salivary glands ultrasonography (SGUS) in the diagnosis and follow-up strategy of patients with suspected pSS. Moreover, new noninvasive tools are emerging, including elastography, a new ultrasonography technique that provides an estimate of tissue elasticity, MRI, MR sialography, and ¹⁸ fluorodeoxyglucose-positron emission tomography. Although new imaging opportunities are available, SGUS should be the first-line choice in pSS because of its accessibility, feasibility over time, and sensitivity to change.

Sonographic Features of Salivary Glands in Sjögren's Syndrome and its Mimics

PURPOSE OF REVIEW

For 30 years, ultrasound has been investigated as a means to evaluate salivary gland abnormalities in patients with autoimmune disease. We aim to review the test characteristics of ultrasound for diagnosing Sjögren's syndrome, the scoring systems used for this purpose, and the ultrasound similarities and differences between Sjögren's syndrome and some of its potential salivary gland mimics.

RECENT FINDINGS

Hypo/anechoic glandular lesions are the major ultrasound characteristic found in Sjögren's syndrome. Most studies have reported such ultrasound abnormalities to have a sensitivity and specificity in the range of 65-85% and 85-95%, respectively, as well as a positive likelihood ratio between 4 and 12. However, similar findings can also be seen in sarcoidosis, amyloidosis, IgG4-related disease, HIV, and lymphoma. A "nodal" pattern of involvement or the ultrasound artifact of "through transmission" can help distinguish some of these mimics from Sjogren's syndrome. Ultrasound can substantially influence the diagnosis of Sjögren's syndrome.

Autoimmune diseases in China

Autoimmune diseases, such as rheumatoid arthritis, systematic lupus erythematosus and Sjögren's syndrome, are a group of diseases characterized by the activation of immune cells and excessive production of autoantibodies. Although the pathogenesis of these diseases is still not completely understood, studies have shown that multiple factors including genetics, environment and immune responses play important roles in the development and progression of the diseases. In China, there are great achievements in the mechanisms of autoimmune diseases during the last decades. These studies provide new insight to understand the diseases and also shed light on the development of novel therapy.

Latest Advances in Ultrasound Assessment of Salivary Glands in Sjögren Syndrome

OBJECTIVE

There are different imaging techniques to assess the parotid glands (i.e., sialography, salivary gland scintigraphy) in patients with Sjögren syndrome (SS). However, their use is limited by the invasive character or high cost. Ultrasound (US) is gaining interest by rheumatologists as a complementary diagnostic tool for SS. To date, there is an increasing body of evidence supporting its sensitivity in the assessment of salivary glands in SS. The aim of our study was to analyze the potential role of US as a diagnostic and prognostic tool in SS and to discuss existing evidence to support its application use.

METHODS

A systematic search was performed in the electronic database PubMed, using the following search terms: (salivary glands OR parotid glands OR submandibular glands) AND Sjögren's syndrome AND (ultrasonography OR ultrasound OR sonography). Titles, abstracts, and full reports were systematically screened.

RESULTS

The results of the studies analyzed in this review show encouraging results in terms of accuracy, validity, and diagnostic value, which leads us to believe that in the future US could become the reference imaging tool to assess SS. The studies include a small cohort of patients, and there is no standardized approach in terms of US techniques for the assessment of salivary glands.

CONCLUSIONS

Ultrasound of major salivary glands is a useful tool for diagnosis, prognostic evaluation, and response to treatment in SS. The use of this imaging technology is still under development, and more multicentric studies are needed to validate this tool.

Diagnostic value of major salivary gland ultrasonography in primary Sjögren's syndrome: the role of grey-scale and colour/power Doppler sonography

Primary Sjögren's syndrome (pSS) is an autoimmune connective tissue disease characterized primarily by chronic inflammatory involvement of the exocrine glands, particularly the salivary glands. The use of ultrasound in the study of salivary glands (SGUS) has expanded considerably in recent years. The ultrasound can document structural alterations that can be visualized as hyperechogenic and hypoechogenic areas, or as areas with non-homogeneous echogenicity. To date, several systems of SGUS scoring systems of abnormalities during pSS are available. From the studies published in recent decades, it has been possible to document the high sensitivity and specificity of the pathological findings that can be documented by SGUS. SGUS can also provide added value in identifying patients at risk for developing disease complications such as lymphoma. The Doppler technique can also supply information about glandular tissue vascularization, which is very useful for diagnostic and differential purposes. In this review we will present the state of the art of SGUS, with a prevailing focus on diagnostic use and possible future developments.

Video clip assessment of a salivary gland ultrasound scoring system in Sjögren's syndrome using consensual definitions: an OMERACT ultrasound working group reliability exercise

OBJECTIVE

To develop ultrasound (US) definitions and a US novel scoring system for major salivary gland (SG) lesions in patients with primary Sjögren's syndrome (pSS) and to test their intrareader and inter-reader reliability using US video clips.

METHODS

Twenty-five rheumatologists were subjected to a three-round, web-based Delphi process in order to agree on (1) definitions and scanning procedure of salivary gland ultrasonography (SGUS): parotid, submandibular and sublingual glands (PG, SMG and SLG); (2) definitions for the elementary SGUS lesions in patients with Sjögren's syndrome; (3) scoring system for grading changes. The experts rated the statements on a 1-5 Likert scale. In the second step, SGUS video clips of patients with pSS and non-pSS sicca cases were collected containing various spectrums of disease severity followed by an intrareader and inter-reader reliability exercise. Each video clip was evaluated according to the agreed definitions.

RESULTS

Consensual definitions were developed after three Delphi rounds. Among the three selected SGs, US assessment of PGs and SMGs was agreed on. Agreement was reached to score only greyscale lesions and to focus on anechoic/hypoechoic foci in a semiquantitative matter or, if not possible on a qualitatively (present/absent) evaluation of fatty or fibrous lesions. Intrareader reliability for detecting and scoring these lesions was excellent (Cohen's kappa 0.81) and inter-reader reliability was good (Light's kappa 0.66).

CONCLUSION

New definitions for developing a novel semiquantitative US score in patients with pSS were developed and tested on video clips. Inter-reader and intrareader reliabilities were good and excellent, respectively.

Diagnostic accuracy of salivary gland ultrasonography with different scoring systems in Sjögren's syndrome: a systematic review and meta-analysis

Noninvasive objective salivary gland ultrasonography (SGU) had been widely used to evaluate major salivary gland involvement in primary Sjögren’s syndrome (pSS) and treatment responses. However, the evaluation score, diagnostic sensitivity, and diagnostic specificity significantly varied among clinical studies. We conducted this meta-analysis to assess the diagnostic accuracy of different SGU scoring systems using the American-European Consensus Group criteria. Of the 1301 articles retrieved from six databases, 24 met the criteria for quality assessment and 14 for meta-analyses. The pooled sensitivities were 75% (0–4) with I² = 92.0%, 84% (0–16) with I² = 63.6%, and 75% (0–48) with I² = 90.9%; the pooled specificities were 93% (0–4) with I² = 71.5%, 88% (0–16) with I² = 65.4%, and 95% (0–48) with I² = 83.9%; the pooled diagnostic odds ratios were 71.26 (0–4) with I² = 0%, 46.3 (0–16) with I² = 73.8%, and 66.07 (0–48) I² = 0%; the areas under the SROC curves were 0.95 (0–4), 0.93 (0–16), and 0.94 (0–48). These results indicated that the 0–4 scoring system has a higher specificity and a less heterogeneity than other systems, and could be used as a universal SGU diagnostic standard.

What is the best salivary gland ultrasonography scoring methods for the diagnosis of primary or secondary Sjögren's syndromes?

OBJECTIVE

To evaluate the performance of salivary gland ultrasonography for the diagnosis of primary and secondary Sjögren's syndromes (pSS and sSS).

METHOD

Multicenter cross-sectional study on 97 patients with clinical sicca symptoms. The pSS (n = 22) met the American-European Consensus Group (AECG) classification criteria. The control patients (n = 36) with sicca symptoms did not fulfill the AECG criteria. Four scores were used to evaluate the 4 major salivary gland echostructure: the Salaffi score (0-16), Jousse-Joulin score (0-4), Hocevar score (0-48) and Milic score (0-12).

RESULTS

The medians of ultrasonographic (US) scores were higher in the pSS and sSS groups than in the control group (P < 0.001). The receiver-operating characteristic (ROC) curves and the positive likelihood ratio (LR+) of the four scores showed a good diagnostic performance for the US diagnosis of pSS and sSS. Respectively, for pSS and sSS, the AUC were 0.891 (95%CI 0.812-0.970) and 0.824 (95%CI 0.695-0.954) for Hocevar score, 0.885 (95%CI 0.804-0.965) and 0.808 (95%CI 0.673-0.943) for Milic score, 0.915 (95%CI 0.848-0.982) and 0.844 (95%CI 0.724-0.965) for Salaffi score, 0.897 (95%CI 0.821-0.973) and 0.851 (95%CI 0.735-0.968) for Jousse-Joulin score. This study showed an interesting inter-observer reproducibility (kappa = 0.714 ± 0.131) of the US evaluation with 85.7% agreement between reader to determine the pathological character of the salivary glands.

CONCLUSION

Salivary gland US is a simple, non-invasive and performant imaging procedure for the diagnosis of pSS and sSS, with Salaffi, Milic and Jousse-Joulin scores.

Ultrasound elastography in assessment of salivary glands involvement in primary Sjögren's syndrome

OBJECTIVE

Our study aimed to assess the pathological sonoelastographic changes in the major salivary glands and to demonstrate the diagnostic effectiveness of Sonoelastography as an additional method to US in Sjögren's syndrome.

METHODS

Fifty eight patients with primary Sjögren's syndrome (pSS) were selected according to the American-European Consensus Group Classification criteria. Twenty five healthy volunteers involved in this study. All patients were evaluated with B-mode and elastography by using Hitachi EUB 7500 digital ultrasound equipment. All subjects were female. The sonoelastography examination, which allowed us to assess the elasticity of the parenchyma, was performed and strain ratios were measured by comparing with the adjacent tissues.

RESULTS

Statistically significant differences were found between the pSS and control groups for the elastographic scores and strain ratios (p < 0.001). The highest sensitivity and specificity levels were obtained when the strain ratio cut-off value was taken as 1.55 for the submandibular gland and 2.45 for the parotid gland (sensitivity and specificity were 83% and 88% respectively for the submandibular gland and 83% and 92% respectively for the parotid gland). However, no statistically significant differences were found between the disease duration and the elasticity scores or strain ratios in pSS group (p > 0.05).

CONCLUSION

US examination is an efficient method to assess major salivary gland involvement in the diagnosis of pSS. Sonoelastography is a modality which can contribute to the diagnosis by improving specificity in the differential diagnosis of pSS. Strain ratio measurement, which is a semi-quantitative method, increases the diagnostic effectiveness by providing high sensitivity, specificity, and negative predictive values.

Scoring hypoechogenic areas in one parotid and one submandibular gland increases feasibility of ultrasound in primary Sjögren's syndrome

OBJECTIVE

To assess whether ultrasonographic scoring of (i) both parotid and submandibular salivary glands and (ii) all individual components of the Hocevar scoring system, is needed for classifying patients as primary Sjögren's syndrome (pSS).

METHODS

Ultrasound examination of the major salivary glands (sUS) was performed in 204 consecutive patients clinically suspected (n=171) or diagnosed (n=33) with pSS.Parenchymal echogenicity, homogeneity, hypoechogenic areas, hyperechogenic reflections and salivary gland posterior border were scored in left and right parotid and submandibular glands. Logistic regression analyses were performed to assess which glands and sUS components contributed significantly to classification as pSS or non-pSS according to the 2016 American College of Rheumatology-European League Against Rheumatism (ACR-EULAR) criteria.

RESULTS

116 (57%) patients were classified as pSS, the remaining as non-pSS. Instead of scoring both sides (area under the curve; AUC=0.856, Nagelkerke R²=0.526), multivariate analysis showed that sUS scoring of only right (AUC=0.850; R²=0.518) or left (AUC=0.852; R²=0.511) parotid and submandibular glands is sufficient to predict ACR-EULAR classification. Moreover, all individual components of the Hocevar scoring system significantly predicted classification. Multivariate analysis showed that parenchymal echogenicity and hypoechogenic areas contributed independently to ACR-EULAR classification (AUC=0.857; R²=0.539). Scoring these components in one parotid and one submandibular gland highly predicted ACR-EULAR classification (AUC=0.855; R²=0.539). Scoring only hypoechogenic areas on one side showed almost similar results (AUC=0.846; R²=0.498).

CONCLUSION

sUS examination of parotid and submandibular glands on one side is sufficient to predict classification of patients according to the ACR-EULAR criteria. To further increase feasibility of sUS in outpatient clinics worldwide, only hypoechogenic areas can be scored.

Ultrasonography of major salivary glands compared with parotid and labial gland biopsy and classification criteria in patients with clinically suspected primary Sjögren's syndrome

OBJECTIVE

To assess the validity of ultrasound of major salivary glands (sUS) compared with parotid and labial gland biopsies, sialometry, anti-SSA/Ro antibody status and classification criteria in patients clinically suspected with primary Sjögren's syndrome (pSS).

METHODS

103 consecutive outpatients with clinically suspected pSS underwent sUS. Parenchymal echogenicity, homogeneity, hypoechogenic areas, hyperechogenic reflections and clearness of salivary gland border were scored according to the Hocevar scoring system. Total ultrasound score was calculated as the sum of these domains (range 0-48).

RESULTS

Absolute agreement between sUS and parotid (83%) and labial (79%) gland biopsy outcome was good. Negative sUS predicts negative parotid gland biopsy, and positive sUS predicts positive labial gland biopsy. Compared with the American European Consensus Group (AECG) classification, sUS showed an absolute agreement of 82%, sensitivity of 71% and specificity of 92%. Compared with the American College of Rheumatology (ACR) classification, absolute agreement was 86%, sensitivity was 77% and specificity was 92%. Compared with the ACR-European League Against Rheumatism (EULAR) classification, absolute agreement was 80%, sensitivity was 67% and specificity was 94%. Positive sUS predicts classification, but negative sUS does not exclude classification. The combination of positive sUS with presence of anti-SSA/Ro antibodies or negative sUS with absence of anti-SSA/Ro antibodies showed a high predictive value for classification as pSS or non-pSS.

CONCLUSION

In our prospective inception cohort study derived from daily clinical practice, absolute agreement between sUS and salivary gland biopsies was slightly higher for parotid compared with labial gland biopsies. The combination of positive sUS and presence of anti-SSA/Ro antibodies highly predicts classification according to the AECG, ACR and ACR-EULAR classification criteria.

Standards for the assessment of salivary glands - an update

The paper is an update of 2011 Standards for Ultrasound Assessment of Salivary Glands, which were developed by the Polish Ultrasound Society. We have described current ultrasound technical requirements, assessment and measurement techniques as well as guidelines for ultrasound description. We have also discussed an ultrasound image of normal salivary glands as well as the most important pathologies, such as inflammation, sialosis, collagenosis, injuries and proliferative processes, with particular emphasis on lesions indicating high risk of malignancy. In acute bacterial inflammation, the salivary glands appear as hypoechoic, enlarged or normal-sized, with increased parenchymal flow. The echogenicity is significantly increased in viral infections. Degenerative lesions may be seen in chronic inflammations. Hyperechoic deposits with acoustic shadowing can be visualized in lithiasis. Parenchymal fibrosis is a dominant feature of sialosis. Sjögren syndrome produces different pictures of salivary gland parenchymal lesions at different stages of the disease. Pleomorphic adenomas are usually hypoechoic, well-defined and polycyclic in most cases. Warthin tumor usually presents as a hypoechoic, oval-shaped lesion with anechoic cystic spaces. Malignancies are characterized by blurred outlines, irregular shape, usually heterogeneous echogenicity and pathological neovascularization. The accompanying metastatic lesions are another indicator of malignancy, however, final diagnosis should be based on biopsy findings.

Combination of Salivary Gland Ultrasonography and Virtual Touch Quantification for Diagnosis of Sjögren's Syndrome: A Preliminary Study

A total of 136 subjects (51 SS patients, 35 sicca syndrome patients without SS, and 50 healthy volunteers) were enrolled in this study. The mean SWV value for salivary glands of SS patients was statistically higher than that of controls (2.81 ± 0.66 m/s versus 1.85 ± 0.28 m/s for parotid glands and 2.29 ± 0.34 m/s versus 1.82 ± 0.25 m/s for submandibular glands, resp.). Combining SWV values of parotid and submandibular glands gives a sensitivity of 88.2% (95% CI: 76.1-95.6%) and specificity of 96.0% (95% CI: 86.3-99.5%) at the cutoff point of 2.19 m/s, with an AUROC of 0.954 (95% CI: 0.893-0.986). In addition, combining SGUS score and SWV value yields a sensitivity of 98.0% (95% CI: 89.6-100%), specificity of 90.0% (95% CI: 78.2-96.7%), and AUROC of 0.962 (95% CI: 0.904-0.990). Classification tree considering the sequential use of SGUS score and SWV value achieved 92.1% accuracy for diagnosis of SS. Similarly, the ROC curve of combined SGUS scores and SWV values yields an AUROC of 0.954 (95% CI: 0.885-0.987), sensitivity of 97.1% (95% CI: 85.1-99.9%), and specificity of 92.2% (95% CI: 81.1-97.8%) for separating sicca syndrome patients (without SS) from SS patients. Combining SGUS and VTQ provides a promising tool for diagnosis of SS.

[Clinical usefulness of salivary gland ultrasonography in Sjögren's syndrome: Where are we now?]

Salivary gland ultrasonography is a simple, noninvasive and inexpensive procedure, which provides valuable information for the diagnosis of primary Sjögren's syndrome (pSS). The main sonographic characteristic of the major salivary glands (parotid and submandibular) in pSS patients is the heterogeneity of the parenchyma, with the appearance of hypoechoic areas. Numerous studies published over the past 20 years report a sensitivity of 70% and a specificity of more than 90% for the diagnosis of pSS. Before the widespread use of this procedure in daily practice and its integration into classification criteria of the disease, it has yet to be validated in terms of reproducibility and a consensus score should be established. This work is being conducted by an international group of experts. Other ultrasound techniques such as elastography could also be of interest to objectively quantify changes in the glandular tissue that occur during the disease.