Relationship of MR imaging of submandibular glands to hyposalivation in Sjögren's syndrome

The Novel OMERACT Ultrasound Scoring System for Salivary Gland Changes in Patients With Sjögren Syndrome Is Associated With MRI and Salivary Flow Rates

OBJECTIVE

To assess the construct validity of the novel Outcome Measures in Rheumatology (OMERACT) ultrasound (US) semiquantitative scoring system for morphological lesions in major salivary glands by comparing it with magnetic resonance imaging (MRI) and unstimulated whole salivary flow rates (U-WSFRs) in patients with primary Sjögren syndrome (pSS).

METHODS

Nine sonographers applied the OMERACT 0-3 grayscale scoring system for parotid (PGs) and submandibular glands (SMGs) in 11 patients with pSS who also had MRIs performed. These were evaluated by 2 radiologists using a semiquantitative 0-3 scoring system for morphological lesions. The agreement between US and MRI and the association between U-WSFRs and imaging structural lesions was determined. A score ≥ 2 for both US and MRI was defined as gland pathology.

RESULTS

The prevalence of US morphological lesions in 11 patients with a score ≥ 2 was 58% for PGs and 76% for SMGs, and 46% and 41% for PGs and SMGs, respectively, for MRI. The agreement between OMERACT US scores and MRI scores was 73-91% (median 82%) in the right PG and 73-91% (median 91%) in the left PG, 55-91% (median 55%) in the right SMG and 55-82% (median 55%) in the left SMG. When relations between the presence of hyposalivation and an US score ≥ 2 were examined, agreement was 91-100% (median 83%) in both PGs and 55-91% (median 67%) in both SMGs.

CONCLUSION

There is moderate to strong agreement between the OMERACT US and MRI scores for major salivary glands in patients with pSS. Similar agreement ratios were observed between the higher OMERACT US scores and presence of hyposalivation.

Correlations of MR Sialographic Gradings with the Clinical Measures of Sjögren's Syndrome

OBJECTIVES

Sjögren syndrome (SS) features salivary gland architectural changes such as ductal deformities and fat deposition secondary to inflammatory cell infiltrates; however, the anatomical and pathophysiological correlations of SS remain to be determined. This study aimed to determine the correlations of imaging findings based on the magnetic resonance (MR) sialography with the clinical and laboratory aspects of SS patients.

METHODS

We evaluated the MR sialographic findings of two pairs of parotid glands (PGs) and submandibular glands (SMGs) from 41 SS patients. The distinct MR sialographic features were then compared with the clinical symptoms, biological (anti-SSA/Ro antibody positivity), histological (labial gland focus score), and functional (salivary flow and scintigraphy) data.

RESULTS

Ductal deformities such as sialectasis in the PG ducts were exclusively observed in SS, and fat replacement in SMGs was more distinct in patients with SS than in non-SS sicca patients. Of the 82 PGs and SMGs from 41 SS patients, the grade of sialectasis in PGs on MR sialographic images and fat stage in SMGs showed strong correlations with anti-SSA/Ro-positivity. PG sialectasis was found more frequently in patients with dry mouth and decreased salivary gland function. A significant correlation was found between fat deposition in PGs and SMGs and decreased salivary gland function.

CONCLUSION

These results suggest that MR sialography is a reliable, adjunctive anatomical and functional study to assess SS. Detail aspects of sialectasis and fat accumulation encountered on MR sialography in SS patients can help physicians assume the disease status in SS.

LEVEL OF EVIDENCE

3 Laryngoscope, 133:307-316, 2023.

Imaging characteristics of Sjögren's syndrome

The current workup of Sjögren's syndrome is based on diagnostic criteria involving a combination of histology, immunology, ophthalmology, and salivary flow. Several modern imaging techniques provide complementary and additional information to diagnosis, staging, and surveillance. In this review article, we discuss the characteristic salivary imaging findings seen with the most commonly utilized imaging modalities. We also discuss imaging findings of the central nervous system disorders associated with Sjögren's syndrome, including the neuromyelitis optica spectrum disorder, and provide a differential diagnosis of alternative etiologies that can mimic Sjögren's syndrome.

Association of Hyper-Low-Density Lipoprotein and Hypo-High-Density Lipoprotein Cholesterolemia with Low Saliva Flow Rates in Japanese Community-Dwelling Elders

Introduction  The associations of low-density lipoprotein cholesterol (LDL-C) and high-density lipoprotein (HDL-C) with reduced saliva flow rates have not been previously reported. Objective  The present study aimed to assess the association of cholesterolemia with reduced saliva flow rates in community-dwelling elderly subjects. Methods  The present study analyzed 342 participants (170 males and 172 females aged between 78 and 79 years old). Unstimulated salivary flow rate (USFR) was assessed using a cotton roll method. Low-USFR was defined as 0.10 g/30 seconds. Stimulated salivary flow rate (SSFR) was assessed by having the participants chew tasteless gum for 3 minutes. Low-SSFR was defined as 1.0 mL/minute. Blood samples were collected for the measurement of LDL-C, HDL-C, rheumatoid factor, hemoglobin A1c, and creatinine. To assess depression, the General Health Questionnaire 30 was used. A standardized questionnaire was completed, covering the current and previous medications of the participants and smoking status. We stratified the serum LDL-C levels of the participants as normal, moderate or severe hyper-LDL cholesterolemia and serum HDL-C levels as normal or hypo-HDL cholesterolemia. Multivariate logistic regression models were established and low-USFR or low-SSFR were set as dependent variables in the aforementioned models. Results  After controlling for the effects of the other variables, the odds ratios (ORs) (95% confidence intervals [CIs]) for low-USFR were 2.25 (1.10-4.61) for moderate and 5.69 (1.55-20.8) for severe hyper-LDL cholesterolemia, while that of hypo-HDL cholesterolemia was 3.40 (1.33-8.69). Severe hyper-LDL cholesterolemia was also associated with low-SSFR with an OR of 3.89 (1.39-10.88). Conclusion  Elderly patients with cholesterolemia have a risk of reduced salivary flow rate.

Comparative Study of Multiple High-Signal-Intensity Spots on 3D and 2D Magnetic Resonance Sialography for Patients with Sjögren's Syndrome

We investigated the sensitivities of 2-dimensional (2D) magnetic resonance sialography (MR-S) and unilateral sagittal and axial 3-dimensional (3D) MR-S using a surface coil and their combination in diagnosing patients with Sjögren's syndrome (SS). We retrospectively analyzed the 3D and 2D MR-S results of 78 patients with SS. We evaluated the sensitivities of multiple high-signal-intensity spots and staging on MR sialograms and analyzed the efficient imaging methods and cross section for diagnosing patients with SS. The sensitivities of MR-S for detecting abnormal findings (i.e., MR-S stage 1 or higher) were as follows: 65 cases (83.3% [95% confidence interval (CI): 73.2-90.8]) for unilateral sagittal 3D MR-S; 62 cases (79.4% [95% CI: 68.8-87.8]) for axial 3D MR-S; 66 cases (84.6% [95% CI: 74.7-91.8]) for combined unilateral sagittal and axial 3D MR-S; and 32 cases (41.0% [95% CI: 30.0-52.7]) for bilateral sagittal 2D MR-S. The ratio of the abnormal finding of MR-S was tested using the two-tailed Fisher's exact test. Unilateral sagittal, axial, and combined unilateral sagittal and axial 3D MR-S showed significantly higher sensitivity than bilateral sagittal 2D MR-S, respectively (P < 0.001). Most cases upstaged by 3D MR-S were those positive (stage 1 or higher) among the stage 0 cases detected by 2D MR-S. Axial 3D MR-S, compared with 2D MR-S, understaged four cases, which was due to the imaging range of the axial 3D MR-S. We concluded that a single unilateral sagittal 3D MR-S was sufficient and axial 3D MR-S was unnecessary for SS staging. T1- and T2-weighted images are essential for investigating the salivary glands in patients with SS. Therefore, we also concluded that bilateral sagittal 3D MR-S of the parotid glands in addition to T1- and T2-weighted imaging is necessary, sufficient, and most efficient for precise MR imaging examination of the salivary glands, including diagnosing SS.

Ultrasound and Bioptic Investigation of Patients with Primary Sjögren's Syndrome

Primary Sjögren's syndrome (pSS) is a chronic and heterogeneous disorder characterized by a wide spectrum of glandular and extra-glandular features. The hallmark of pSS is considered to be the immune-mediated involvement of the exocrine glands and B-cell hyperactivation. This leads pSS patients to an increased risk of developing lymphoproliferative diseases, and persistent (>2 months) major salivary gland enlargement is a well-known clinical sign of possible involvement by B cell lymphoma. Better stratification of the patients may improve understanding of the mechanism underlying the risk of lymphoproliferative disorder. Here, we summarize the role of different imaging techniques and a bioptic approach in pSS patients, focusing mainly on the role of salivary gland ultrasonography (SGUS) and a US-guided core needle biopsy (Us-guided CNB) as diagnostic and prognostic tools in pSS patients with persistent parotid swelling.

Imaging in Primary Sjögren's Syndrome

Primary Sjögren's syndrome (pSS) is a systemic autoimmune disease characterized by dysfunction and lymphocytic infiltration of the salivary and lacrimal glands. Besides the characteristic sicca complaints, pSS patients can present a spectrum of signs and symptoms, which challenges the diagnostic process. Various imaging techniques can be used to assist in the diagnostic work-up and follow-up of pSS patients. Developments in imaging techniques provide new opportunities and perspectives. In this descriptive review, we discuss imaging techniques that are used in pSS with a focus on the salivary glands. The emphasis is on the contribution of these techniques to the diagnosis of pSS, their potential in assessing disease activity and disease progression in pSS, and their contribution to diagnosing and staging of pSS-associated lymphomas. Imaging findings of the salivary glands will be linked to histopathological changes in the salivary glands of pSS patients.

Comparison of Clinical Characteristics and Magnetic Resonance Imaging of Salivary Glands With Magnetic Resonance Sialography in Sjögren's Syndrome

OBJECTIVES/HYPOTHESIS

To compare the results of magnetic resonance imaging with magnetic resonance sialography (MRSIAL) and the clinical and laboratory characteristics in a well-characterized cohort of patients with primary or secondary Sjögren's syndrome (SS) meeting the American-European Consensus Group criteria.

STUDY DESIGN

Retrospective, observational, monocentric study.

METHODS

Thirty-six patients (81% female, mean age = 48 ± 35 years) with primary or secondary SS who underwent MRSIAL were included in the study.

RESULTS

MRSIAL revealed characteristic radiological signs in the parotid, sublingual, and submandibular salivary glands in 35/36 patients (97%). Patients presenting with anti-Sjögren's syndrome-related antigen A (SSA) autoantibodies showed more often fatty infiltration, a "pepper-and-salt" appearance, ductal stenosis, and/or ductal dilation of the parotid gland (88%, 88%, and 72% respectively) than patients negative for anti-SSA (12%, 4%, and 28% respectively). MRSIAL demonstrated signs characteristic of SS in all 11 patients with negative minor salivary gland biopsy. For 15 patients undergoing ultrasound examination only, 11 (73%) had SS findings, but all 15 had SS findings on MRSIAL. Two cases of parotid lymphoma were detected by MRSIAL (6%).

CONCLUSIONS

MRSIAL is a reliable technique to detect glandular anomalies in patients with SS, and seems to provide a valuable aid in the diagnosis of SS.

LEVEL OF EVIDENCE

4 Laryngoscope, 131:E83-E89, 2021.

Imaging methods in primary Sjögren's syndrome as potential tools of disease diagnostics and monitoring

Primary Sjögren's syndrome (pSS) is a systemic autoimmune disease that affects exocrine glands, especially salivary and lacrimal glands, leading to their progressive destruction. With highly differentiated clinical course the approach to the definition of pSS is constantly evolving and the pSS classification criteria have been modified over the past years. In the past sialography and scintigraphy were frequently used in pSS diagnostics. Recently no imaging method has been included in the pSS classification criteria. That raises the question about the benefits of using novel imaging techniques such as ultrasonography, elastography and magnetic resonance imaging to diagnose and monitor pSS patients. The purpose of this review is to evaluate the advantages and limitations of widely used imaging methods in pSS and their possible future development.

Neurological and Inflammatory Manifestations in Sjögren's Syndrome: The Role of the Kynurenine Metabolic Pathway

For decades, neurological, psychological, and cognitive alterations, as well as other glandular manifestations (EGM), have been described and are being considered to be part of Sjögren's syndrome (SS). Dry eye and dry mouth are major findings in SS. The lacrimal glands (LG), ocular surface (OS), and salivary glands (SG) are linked to the central nervous system (CNS) at the brainstem and hippocampus. Once compromised, these CNS sites may be responsible for autonomic and functional disturbances that are related to major and EGM in SS. Recent studies have confirmed that the kynurenine metabolic pathway (KP) can be stimulated by interferon-γ (IFN-γ) and other cytokines, activating indoleamine 2,3-dioxygenase (IDO) in SS. This pathway interferes with serotonergic and glutamatergic neurotransmission, mostly in the hippocampus and other structures of the CNS. Therefore, it is plausible that KP induces neurological manifestations and contributes to the discrepancy between symptoms and signs, including manifestations of hyperalgesia and depression in SS patients with weaker signs of sicca, for example. Observations from clinical studies in acquired immune deficiency syndrome (AIDS), graft-versus-host disease, and lupus, as well as from experimental studies, support this hypothesis. However, the obtained results for SS are controversial, as discussed in this study. Therapeutic strategies have been reexamined and new options designed and tested to regulate the KP. In the future, the confirmation and application of this concept may help to elucidate the mosaic of SS manifestations.